Download Database

1
25
Accessing
Databases with
JDBC
© 1992-2007 Pearson Education, Inc. All rights reserved.
2
OBJECTIVES
In this chapter you will learn:
 Relational database concepts.
 To use Structured Query Language (SQL) to retrieve
data from and manipulate data in a database.
 To use the JDBC™ API of package java.sql to access
databases.
 To use the RowSet interface from package javax.sql to
manipulate databases.
 To use JDBC 4.0’s automatic JDBC driver discovery.
 To use PreparedStatements to create precompiled SQL
statements with parameters.
 How transaction processing makes database
applications more robust.
© 1992-2007 Pearson Education, Inc. All rights reserved.
3
25.1
25.2
25.3
25.4
25.5
Introduction
Relational Databases
Relational Database Overview: The books Database
SQL
25.4.1 Basic SELECT Query
25.4.2 WHERE Claus
25.4.3 ORDER BY Claus
25.4.4 Merging Data from Multiple Tables: INNER JOIN
25.4.5 INSERT Statement
25.4.6 UPDATE Statement
25.4.7 DELETE Statement
Instructions for installing MySQL and MySQL
Connector/J
© 1992-2007 Pearson Education, Inc. All rights reserved.
4
25.6
25.7
Instructions for Setting Up a MySQL User Account
Creating Database book in MySQL
25.8
Manipulating Databases with JDBC
25.8.1 Connecting to and Querying a Database
25.8.2 Querying the books Database
25.9
RowSet
Interface
25.10 Java DB/Apache Derby
25.11 PreparedStatements
25.12 Stored Procedures
25.13 Transaction Processing
25.14 Wrap-Up
25.15 Web Resources and Recommended Readings
© 1992-2007 Pearson Education, Inc. All rights reserved.
5
25.1 Introduction
 Database
– Collection of data
 DBMS
– Database management system
– Storing and organizing data
 SQL
– Relational database
– Structured Query Language
© 1992-2007 Pearson Education, Inc. All rights reserved.
6
25.1 Introduction (Cont.)
 RDBMS
– Relational database management system
– MySQL
- Open source
- Available for both Windows and Linux
- dev.mysql.com/downloads/mysql/4.0.hml
 JDBC
– Java Database Connectivity
– JDBC driver
- Enable Java applications to connect to database
- Enable programmers to manipulate databases using JDBC
© 1992-2007 Pearson Education, Inc. All rights reserved.
7
Software Engineering Observation 25.1
Using the JDBC API enables developers to
change the underlying DBMS without
modifying the Java code that accesses the
database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
8
25.2 Relational Databases
• Relational database
– Table
• Rows, columns
– Primary key
• Unique data
• SQL queries
– Specify which data to select from a table
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9
Fig. 25.1 | Employee table sample data.
© 1992-2007 Pearson Education, Inc. All rights reserved.
10
Fig. 25.2 | Result of selecting distinct Department and Location
data from table Employee.
© 1992-2007 Pearson Education, Inc. All rights reserved.
25.3 Relational Database Overview: The
books Database
11
• Sample books database
– Four tables
• authors
– authorID, firstName, lastName
• titles
– isbn, title, editionNumber, copyright, publisherID,
imageFile, price
• authorISBN
– authorID, isbn
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12
Column
Description
authorID
Author’s ID number in the database. In the
books database, this integer
column is defined as autoincremented —for each row inserted in this
table, the authorID value is increased by 1 automatically to ensure
that each row has a unique authorID . This column represents the
table’s primary key.
firstName
Author’s first name (a string).
lastName
Author’s last name (a string).
Fig. 25.3 | authors table from the books database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
13
authorID
firstName
lastName
1
Harvey
Deitel
2
Paul
Deitel
3
Andrew
Goldberg
4
David
Choffnes
Fig. 25.4 | Sample data from the authors table.
© 1992-2007 Pearson Education, Inc. All rights reserved.
25.3 Relational Database Overview: The
books Database (Cont.)
14
• Foreign key
– A column
• matches the primary key column in another table
– Helps maintain the Rule of Referential Integrity
• Every foreign key value must appear as another table’s
primary key value
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15
Column
Description
authorID
The author’s ID number, a foreign key to the
isbn
The ISBN for a book, a foreign key to the
authors table.
titles
table.
Fig. 25.5 | authorISBN table from the books database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
16
authorID
isbn
authorID
isbn
1
0131869000
2
0131450913
2
0131869000
1
0131828274
1
0131483986
2
0131828274
2
0131483986
3
0131450913
1
0131450913
4
0131828274
Fig. 25.6 | Sample data from the authorISBN table of books.
© 1992-2007 Pearson Education, Inc. All rights reserved.
17
Column
Description
isbn
ISBN of the book (a string). The table’s primary key. ISBN is an
abbreviation for “International Standard Book Number”
—a
numbering scheme that publishers use to give every book a unique
identification number.
title
Titl e of the book (a string).
editionNumber
Edition number of the book (an integer).
copyright
Copyright year of the book (a string).
Fig. 25.7 | titles table from the books database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
18
isbn
title
editionNumber
copyright
0131869000
Visual Basic How to Program
3
2006
0131525239
Visual C# How to Program
2
2006
0132222205
Java How to Program
7
2007
0131857576
C++ How to Program
5
2005
0132404168
C How to Program
5
2007
0131450913
Internet & World Wide Web
How to Program
3
2004
Fig. 25.8 | Sample data from the titles table of the books database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
25.3 Relational Database Overview: The
books Database (Cont.)
19
• Entity-relationship (ER) diagram
– Tables in the database
– Relationships among tables
• Rule of Entity Integrity
– Primary key uniquely identifies each row
– Every row must have a value for every column of the
primary key
– Value of the primary key must be unique in the table
© 2005 Pearson Education, Inc. All rights reserved.
20
Fig. 25.9 | Table relationships in the books database.
© 1992-2007 Pearson Education, Inc. All rights reserved.
21
Common Programming Error 25.1
Not providing a value for every column
in a primary key breaks the Rule of
Entity Integrity and causes the DBMS to
report an error.
© 1992-2007 Pearson Education, Inc. All rights reserved.
22
Common Programming Error 25.2
Providing the same value for the primary
key in multiple rows causes the DBMS to
report an error.
© 1992-2007 Pearson Education, Inc. All rights reserved.
23
Common Programming Error 25.3
Providing a foreign-key value that does not
appear as a primary-key value in another
table breaks the Rule of Referential
Integrity and causes the DBMS to report
an error.
© 1992-2007 Pearson Education, Inc. All rights reserved.
24
25.4 SQL
• SQL keywords
– SQL queries and statements
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25
SQL keyword
Description
SELECT
Retrieves data from one or more tables.
FROM
Tables involved in the query. Required in every
WHERE
Criteria for selection that determine the rows to be retrieved,
deleted or updated. Optional in a SQL query or
a SQL statement.
GROUP BY
Criteria for grouping rows. Optional in a
SELECT query.
ORDER BY
Criteria for ordering rows. Optional in a
SELECT query.
INNER JOIN
Merge rows from multiple tables.
INSERT
Insert rows into a specified table.
UPDATE
Update rows in a specified table.
DELETE
Delete rows from a specified table.
SELECT.
Fig. 25.10 | SQL query keywords.
© 1992-2007 Pearson Education, Inc. All rights reserved.
26
25.4.1 Basic SELECT Query
• Simplest format of a SELECT query
– SELECT * FROM tableName
• SELECT * FROM authors
• Select specific fields from a table
– SELECT authorID, lastName FROM authors
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27
authorID
lastName
1
Deitel
2
Deitel
3
Goldberg
4
Choffnes
Fig. 25.11 | Sample authorID and lastName data from the authors table.
© 1992-2007 Pearson Education, Inc. All rights reserved.
28
Software Engineering Observation 25.2
For most queries, the asterisk (*) should not be used to specify
column names. In general, you process results by knowing in
advance the order of the columns in the result—for example,
selecting authorID and lastName from table authors ensures
that the columns will appear in the result with authorID as the
first column and lastName as the second column. Programs
typically process result columns by specifying the column number
in the result (starting from number 1 for the first column).
Selecting columns by name also avoids returning unneeded
columns and protects against changes in the actual order of the
columns in the table(s).
© 1992-2007 Pearson Education, Inc. All rights reserved.
29
Common Programming Error 25.4
If you assume that the columns are always
returned in the same order from a query that
uses the asterisk (*), the program may
process the results incorrectly. If the column
order in the table(s) changes or if additional
columns are added at a later time, the order
of the columns in the result would change
accordingly.
© 1992-2007 Pearson Education, Inc. All rights reserved.
30
25.4.2 WHERE Clause
• specify the selection criteria
– SELECT columnName1, columnName2, … FROM
tableName WHERE criteria
• SELECT title, editionNumber, copyright
FROM titles
WHERE copyright > 2002
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31
Portability Tip 25.1
See the documentation for your database
system to determine whether SQL is case
sensitive on your system and to determine
the syntax for SQL keywords (i.e., should
they be all uppercase letters, all lowercase
letters or some combination of the two?).
© 1992-2007 Pearson Education, Inc. All rights reserved.
32
title
editionNumber
copyright
Visual C# How to Program
2
2006
3
2006
Java How to Program
7
2007
C How to Program
5
2007
Visual Basic 2005 How to
Program
Fig. 25.12 | Sampling of titles with copyrights after 2005 from table titles.
© 1992-2007 Pearson Education, Inc. All rights reserved.
33
25.4.2 WHERE Clause (Cont.)
• WHERE clause condition operators
– <, >, <=, >=, =, <>
– LIKE
• wildcard characters % and _
• SELECT authorID, firstName, lastName
FROM authors
WHERE lastName LIKE ‘D%’
© 2005 Pearson Education, Inc. All rights reserved.
34
authorID
firstName
lastName
1
Harvey
Deitel
2
Paul
Deitel
Fig. 25.13 | Authors whose last name starts with D from the authors table.
© 1992-2007 Pearson Education, Inc. All rights reserved.
35
Portability Tip 25.2
Read your database system’s documentation
carefully to determine whether your system
supports the LIKE operator. The SQL we
discuss is supported by most RDBMSs, but it
is always a good idea to check the features of
SQL that are supported by your RDBMS.
© 1992-2007 Pearson Education, Inc. All rights reserved.
36
25.4.2 WHERE Clause (Cont.)
• SELECT authorID, firstName, lastName
FROM authors
WHERE lastName LIKE ‘_i%’
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37
authorID
firstName
lastName
3
Andrew
Goldberg
Fig. 25.14 | The only author from the authors table whose last name
contains o as the second letter.
© 1992-2007 Pearson Education, Inc. All rights reserved.
38
25.4.3 ORDER BY Clause
• Optional ORDER BY clause
– SELECT columnName1, columnName2, … FROM
tableName ORDER BY column ASC
• SELECT authorID, firstName, lastName
FROM authors
ORDER BY lastName ASC
– SELECT columnName1, columnName2, … FROM
tableName ORDER BY column DESC
• SELECT authorID, firstName, lastName
FROM authors
ORDER BY lastName DESC
© 2005 Pearson Education, Inc. All rights reserved.
39
authorID
firstName
lastName
4
David
Choffnes
1
Harvey
Deitel
2
Paul
Deitel
3
Andrew
Goldberg
Fig. 25.15 | Sample data from table authors in ascending order by lastName.
© 1992-2007 Pearson Education, Inc. All rights reserved.
40
authorID
firstName
lastName
3
Andrew
Goldberg
1
Harvey
Deitel
2
Paul
Deitel
4
David
Choffnes
Fig. 25.16 | Sample data from table authors in descending order by lastName.
© 1992-2007 Pearson Education, Inc. All rights reserved.
41
25.4.3 ORDER BY Clause (Cont.)
• ORDER BY multiple fields
– ORDER BY column1 sortingOrder, column2 sortingOrder, …
• SELECT authorID, firstName, lastName
FROM authors
ORDER BY lastName, firstName
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42
authorID
firstName
lastName
4
David
Choffnes
1
Harvey
Deitel
2
Paul
Deitel
4
Andrew
Goldberg
Fig. 25.17 | Sample data from authors in ascending order
by lastName and firstName.
© 1992-2007 Pearson Education, Inc. All rights reserved.
43
25.4.3 ORDER BY Clause (Cont.)
• Combine the WHERE and ORDER BY clauses
• SELECT isbn, title, editionNumber, copyright, price
FROM titles WHERE title LIKE ‘%How to Program’
ORDER BY title ASC
© 2005 Pearson Education, Inc. All rights reserved.
44
isbn
title
edition
- Number
copy- right
0132404168
C How to Program
5
2007
0131857576
C++ How to Program
5
2005
0131450913
Internet and World Wide Web How to Program
3
2004
0132222205
Java How to Program
7
2007
0131869000
Visual Basic 2005 How to
3
2006
013152539
Visual C# How to Program
2
2006
Program
Fig. 25.18 | Sampling of books from table titles whose titles end with
How to Program in ascending order by title.
© 1992-2007 Pearson Education, Inc. All rights reserved.
25.4.4 Merging Data from Multiple Tables:
INNER JOIN
45
• Split related data into separate tables
• Join the tables
– Merge data from multiple tables into a single view
– INNER JOIN
• SELECT columnName1, columnName2, …
FROM table1
INNER JOIN table2
ON table1.columnName = table2.column2Name
• SELECT firstName, lastName, isbn
FROM authors, authorISBN
INNER JOIN authorISBN
ON authors.authorID = authorISBN.authorID
ORDER BY lastName, firstName
© 2005 Pearson Education, Inc. All rights reserved.
46
firstName
lastName isbn
firstName
lastName
isbn
David
Choffnes
0131828274
Paul
Deitel
0131525239
Harvey
Deitel
0131525239
Paul
Deitel
0132404168
Harvey
Deitel
0132404168
Paul
Deitel
0131869000
Harvey
Deitel
0131869000
Paul
Deitel
0132222205
Harvey
Deitel
0132222205
Paul
Deitel
0131450913
Harvey
Deitel
0131450913
Paul
Deitel
0131525239
Harvey
Deitel
0131525239
Paul
Deitel
0131857576
Harvey
Deitel
0131857576
Paul
Deitel
0131828274
Harvey
Deitel
0131828274
Andrew
Goldberg
0131450 913
Fig. 25.19 | Sampling of authors and ISBNs for the books they have written in
ascending order by lastName and firstName.
© 1992-2007 Pearson Education, Inc. All rights reserved.
47
Software Engineering Observation 25.3
If a SQL statement includes columns with the
same name from multiple tables, the statement
must precede those column names with their table
names and a dot (e.g., authors.authorID).
© 1992-2007 Pearson Education, Inc. All rights reserved.
48
Common Programming Error 25.5
Failure to qualify names for columns
that have the same name in two or more
tables is an error.
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49
25.4.5 INSERT Statement
• Insert a row into a table
– INSERT INTO tableName ( columnName1, … , columnNameN )
VALUES ( value1, … , valueN )
• INSERT INTO authors ( firstName, lastName )
VALUES ( ‘Sue’, ‘Smith’ )
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50
authorID
firstName
lastName
1
Harvey
Deitel
2
Paul
Deitel
3
Andrew
Goldberg
4
David
Choffnes
5
Sue
Smith
Fig. 25.20 | Sample data from table Authors after an INSERT operation.
© 1992-2007 Pearson Education, Inc. All rights reserved.
51
Common Programming Error 25.6
It is normally an error to specify a
value for an autoincrement column.
© 1992-2007 Pearson Education, Inc. All rights reserved.
52
Common Programming Error 25.7
SQL uses the single-quote (') character as a delimiter
for strings. To specify a string containing a single
quote (e.g., O’Malley) in a SQL statement, the string
must have two single quotes in the position where the
single-quote character appears in the string (e.g.,
'O''Malley'). The first of the two single-quote
characters acts as an escape character for the second.
Not escaping single-quote characters in a string that is
part of a SQL statement is a SQL syntax error.
© 1992-2007 Pearson Education, Inc. All rights reserved.
53
25.4.6 UPDATE Statement
• Modify data in a table
– UPDATE tableName
SET columnName1 = value1, … , columnNameN = valueN
WHERE criteria
• UPDATE authors
SET lastName = ‘Jones’
WHERE lastName = ‘Smith’ AND firstName = ‘Sue’
© 2005 Pearson Education, Inc. All rights reserved.
54
authorID
firstName
lastName
1
Harvey
Deitel
2
Paul
Deitel
3
Andrew
Goldberg
4
David
Choffnes
5
Sue
Jones
Fig. 25.21 | Sample data from table authors after an UPDATE operation.
© 1992-2007 Pearson Education, Inc. All rights reserved.
55
25.4.7 DELETE Statement
• Remove data from a table
– DELETE FROM tableName WHERE criteria
• DELETE FROM authors
WHERE lastName = ‘Jones’ AND firstName = ‘Sue’
© 2005 Pearson Education, Inc. All rights reserved.
56
authorID
firstName
lastName
1
Harvey
Deitel
2
Paul
Deitel
3
Andrew
Goldberg
4
David
Choffnes
Fig. 25.22 | Sample data from table authors after a DELETE operation.
© 1992-2007 Pearson Education, Inc. All rights reserved.
25.5 Instructions to Install MySQL and
MySQL Connector/J
57
• Install MySQL
– Platform-specific installation requirements:
• dev.mysql.com/doc/refman/5.0/en/general-installationissues.html
– Download your platform’s installer from:
• dev.mysql.com/downloads/mysql/5.0.html
• Need only the Windows Essentials package on Microsoft
Windows
– Follow installation instructions for your platform:
• dev.mysql.com/doc/refman/5.0/en/installing.html
© 2005 Pearson Education, Inc. All rights reserved.
25.5 Instructions to Install MySQL and
MySQL Connector/J
58
• MySQL Server Instance Configuration Wizard
– Click Next > then select Standard Configuration and
click
Next > again.
– Not necessary to install MySQL as a Windows service for
our examples
• Uncheck Install as a Windows Service
• Check Include Bin Directory in Windows PATH
– Click Next > then click Execute to perform the server
configuration.
– Click Finish to close the wizard.
© 2005 Pearson Education, Inc. All rights reserved.
25.5 Instructions to Install MySQL and
MySQL Connector/J
59
• Install MySQL Connector/J
– Must install Connector/J JDBC driver from:
• dev.mysql.com/downloads/connector/j/
5.0.html
– Download mysql-connector-java-5.0.4.zip
– Extract mysql-connector-java-5.0.4.zip to your hard disk into
the folder mysql-connector-java-5.0.4
– Documentation for MySQL Connector/J is in
connector-j.pdf in the docs subdirectory of
mysql-connector-java-5.0.4
– Docs also online at dev.mysql.com/doc/connector/j/en/
connector-j.html
© 2005 Pearson Education, Inc. All rights reserved.
25.6 Instructions on Setting MySQL User
Account
60
• Set up a user account
– Start database server
• mysqld-nt.exe on Windows
– Start the MySQL monitor
• mysql –h localhost –u root
– Select the built-in database mysql
•
USE mysql;
– Add the user account jhtp7 and specify privileges
• create user 'jhtp7'@'localhost' identified by 'jhtp7';
• grant select, insert, update, delete, create, drop, references, execute
on *.* to 'jhtp7'@'localhost';
– Exit the MySQL Monitor
• exit;
© 2005 Pearson Education, Inc. All rights reserved.
61
25.7 Creating Database books in MySQL
• Create books database
– Open Command Prompt and change to the directory
containing the SQL script books.sql
– Start the MySQL monitor
• mysql –h localhost –u jhtp7 –p
– Execute the script
• source books.sql;
– Exit the MySQL Monitor
• exit;
© 2005 Pearson Education, Inc. All rights reserved.
62
25.8 Manipulating Databases with JDBC
• Connect to a database
• Query the database
• Display the results of the query in JTable
© 2005 Pearson Education, Inc. All rights reserved.
25.8.1 Connecting to and Querying a
Database
63
• DisplayAuthors
– Retrieves the entire authors table
– Displays the data in the standard output stream
– Example illustrates
• Connect to the database
• Query the database
• Process the result
© 2005 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.23: DisplayAuthors.java
2
// Displaying the contents of the authors table.
3
import
java.sql.Connection;
4
import
java.sql.Statement;
5
import
java.sql.DriverManager;
6
import
java.sql.ResultSet;
7
import
java.sql.ResultSetMetaDat a ;
8
import
java.sql.SQLException;
Outline
Imports for the JDBC classes and
interfaces from package java.sql
class
DisplayAuthors .java
(1 of 3 )
9
10 public
64
DisplayAuthors
11 {
12
// JDBC driver name and database URL
13
static final
String
D R I V E R = "com.mysql.jdbc.Driver" ;
14
static
St ring
D A T A B A S E _ U R=L " j d b c : m y s q l : / / l o c a l h o s t / b o o k s " ;
final
15
16
// launch the application
17
public
18
static
v o i d main( String args[] )
Declare a String
constant that specifies
the database URL
{
19
Connection connection =
20
Statement statement =
null ; // query statement
21
ResultSet resultSet =
null ; // manages results
Declare a String constant
that specifies the JDBC
driver’s class name
null ; // manages connection
22
// connect to database books and query database
23
try
24
25
{
26
// load the driver class
27
Class.forName(
28
D R I V E R );
Loads the class definition
for the database driver.
© 1992-2007 Pearson Education, Inc. All rights reserved.
29
// establish connection to database
30
connection =
DriverManager.getConnection(
31
D A T A B A S E _ U,R L"jhtp7" , "jhtp7" );
32
33
// create Statement for querying database
34
statement
65
connection.createStatement();
Invokes ConnectionDisplayAuthors
method
.java
createStatement to obtain an object
// query database
Use theinterface
Statement
(2 of 3Statement.
) object’s
that implements
resultSet = statement.executeQuery(
executeQuery method to
"SELECT authorID, firstName, lastName FROM authors" );
execute a query that selects
all the author information
// process query results
Obtains the metadata
ResultSetMetaData metaData = resultSet.getMetaData();
from
table authors.
Uses
ResultSetMetaData
for
the
ResultSet.
int numberOfColumns = metaData.getColumnCoun
t();
method getColumnCount
System.out.println(
"Authors Table of Books Database:\n" );
to retrieve the number of
f o r ( int i = 1; i <= numberOfColumns; i++ )
columns in the ResultSet.
Obtain column
System.out.printf(
" %- 8 s\t " , metaData.getColumnName( i ) );
name using method
System. out.println();
getColumnName
Position the ResultSet cursor to the first
while ( resultSet.next() )
row in the ResultSet with method next
{
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
f o r ( int i =
51
1; i <= numberOfColumns; i++ )
System.out.printf(
52
System.out.p
53
}
54
55
=
Initialize a
Outline
Connection
reference
called connection.
}
// end while
rintln();
" %- 8 s\t " , resultSet.getObject( i )
);
Extract the contents
of one column in the
current row
// end try
© 1992-2007 Pearson Education, Inc. All rights reserved.
c a t c h ( SQLException
56
sqlException )
sqlException.printStackTrace();
58
}
59
// end catch
c a t c h ( ClassNotFoundException
60
classNotFound.printStackTrace();
62
}
63
// end catch
64
finally
65
{
66
try
67
{
// ensure resultSet, statement and connection
68
resultSet.close();
69
statement.close();
70
connection.close();
71
} // end try
72
c a t c h ( Exception exception )
73
{
66
classNotFound )
{
61
DisplayAuthors
.java
ClassNotFoundException
is
thrown if the class loader
(3 of 3 )
arecannot
closed locate the driver class
Close the Statement and
the database Connection.
exception.printStackTrace();
74
} // end catch
75
} // end finally
76
77
Catch SQLException, which is
Outline
thrown if the query execution
or
ResultSet process fails
{
57
}
// end main
78 } // end class DisplayAuthors
Authors Table of Books Database:
authorID
1
2
3
4
firstName
Harvey
Paul
Andrew
David
lastName
Deitel
Deitel
Goldberg
Choffnes
© 1992-2007 Pearson Education, Inc. All rights reserved.
67
Software Engineering Observation 25.4
Most major database vendors provide their
own JDBC database drivers, and many
third-party vendors provide JDBC drivers as
well. For more information on JDBC drivers,
visit the Sun Microsystems JDBC Web site,
servlet.java.sun.com/products/
jdbc/drivers.
© 1992-2007 Pearson Education, Inc. All rights reserved.
68
Software Engineering Observation 25.5
Most database management systems require
the user to log in before accessing the
database contents. DriverManager method
getConnection is overloaded with versions
that enable the program to supply the user
name and password to gain access.
© 1992-2007 Pearson Education, Inc. All rights reserved.
69
RDBMS
Database URL format
MySQL
jdbc:mysql://
ORACLE
jdbc:oracle:thin:@
DB2
jdbc:db2: hostname : portNumber /databaseName
Java DB/Apache Derby
jdbc:derby: dataBaseName (embedded) !
hostname : portNumber /databaseName
hostname : portNumber : databaseName
jdbc:derb y:// hostname : portNumber /databaseName (network) !
Microsoft SQL Server
jdbc:sqlserver://
Sybase
jdbc:sybase:Tds:
hostname : portNumber ; databaseName=dataBaseName
hostname : portNumber /databaseName
Fig. 25.24 | Popular JDBC database URL formats.
© 1992-2007 Pearson Education, Inc. All rights reserved.
70
Software Engineering Observation 25.6
Metadata enables programs to process
ResultSet contents dynamically when
detailed information about the
ResultSet is not known in advance.
© 1992-2007 Pearson Education, Inc. All rights reserved.
71
Common Programming Error 25.8
Initially, a ResultSet cursor is positioned
before the first row. Attempting to access a
ResultSet’s contents before positioning the
ResultSet cursor to the first row with
method next causes a SQLException.
© 1992-2007 Pearson Education, Inc. All rights reserved.
72
Performance Tip 25.1
If a query specifies the exact columns to select
from the database, the ResultSet contains the
columns in the specified order. In this case, using
the column number to obtain the column’s value
is more efficient than using the column name.
The column number provides direct access to the
specified column. Using the column name
requires a search of the column names to locate
the appropriate column.
© 1992-2007 Pearson Education, Inc. All rights reserved.
73
Common Programming Error 25.9
Specifying column number 0 when
obtaining values from a ResultSet
causes a SQLException.
© 1992-2007 Pearson Education, Inc. All rights reserved.
74
Common Programming Error 25.10
Attempting to manipulate a ResultSet after
closing the Statement that created the
ResultSet causes a SQLException. The
program discards the ResultSet when the
corresponding Statement is closed.
© 1992-2007 Pearson Education, Inc. All rights reserved.
75
Software Engineering Observation 25.7
Each Statement object can open only one
ResultSet object at a time. When a
Statement returns a new ResultSet, the
Statement closes the prior ResultSet. To
use multiple ResultSets in parallel,
separate Statement objects must return the
ResultSets.
© 1992-2007 Pearson Education, Inc. All rights reserved.
76
25.8.2 Querying the books Database
• Allow the user to enter any query into the
program
• Display the results of a query in a JTable
© 2005 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.25: ResultSetTableModel.java
2
// A TableModel that supplies ResultSet data to a JTable.
3
import
java.sql.Connection;
4
import
java.sql.Statement;
5
import
java.sql.DriverManager;
6
import
java.sql.ResultSet;
7
i m p o r t java.sql.Re s u l t S e t M e t a D a t a ;
8
import
java.sql.SQLException;
9
import
javax.swing.table.AbstractTableModel;
Outline
77
ResultSetTable
Model.java
(1 of 7 )
10
11 // ResultSet rows and columns are counted from 1 and JTable
12 // rows and columns are counted from 0. When processing
13 // ResultSet rows
or columns for use in a JTable, it is
14 // necessary to add 1 to the row or column number to manipulate
15 // the appropriate ResultSet column (i.e., JTable column 0 is
16 // ResultSet column 1 and JTable row 0 is ResultSet row 1).
17 public
c l a s s ResultSetTableModel
e x t e n d s AbstractTableModel
18 {
19
private
Connection connection;
20
private
Statement statement;
21
private
ResultSet resultSet;
22
private
ResultSetMetaData
23
private
int numberOfRows;
metaData;
Class ResultSetTableModel extends
class AbstractTableModel, which
implements interface TableModel.
24
25
// keep track of database connection status
26
p r i v a t e b o o l e a n connectedToDatabase = f a l s e ;
27
Instance variable keeps track
of database connection status
© 1992-2007 Pearson Education, Inc. All rights reserved.
28
// constructor initializes resultSet and obtains its meta data object;
29
// determines number of rows
30
public
Establishes a connection
ClassNotFoundException
to the database.
String password, String query )
31
t h r o ws
32
33
ResultSetTableModel( String driver, String url, String username,
Constructor
SQLException,
{
34
Class.forName( driver );
35
// connect to database
accepts five String
arguments—the driver class
name, the database URL, the
ResultSetTable
username, the password
and the
Model.java
default query to perform
connection = DriverManager.getConnection( url, username, password );
36
37
38
// create Statement to query database
39
statement = connection.createStatement(
40
ResultSet.TYPE_SCROLL_INSENSITIVE
,
41
ResultSet.CONCUR_READ_ONLY
);
Outline
78
(2 of 7 )
Invokes Connection
method createStatement to
create a Statement object.
42
43
// update database connection status
44
connectedToDatabase
= t r u e;
45
46
// set query and execute it
47
setQuery( query );
48
49
}
// end constructor
Indicate that connect to
database is successful
Invokes ResultSetTableModel
method setQuery to perform
ResultSetTableModel
the default query.
© 1992-2007 Pearson Education, Inc. All rights reserved.
50
// get class that represents column type
51
public
52
Class getColumnClass(
int
column )
t h r o w s IllegalStateException
Outline
{
53
// ensure database connection is available
54
if
( !connectedToDatabase )
t h r o w n e w IllegalStateException(
55
56
57
// determine Java class of column
58
try
Verify database
Override method getColumnClass to obtain a
connection
status
"Not Connected to Database" );
Class object that representsResultSetTable
the superclass of
Model.java
all objects in a particular column
{
59
String
60
className
=
79
metaData.getColumnClassName(column
(3 of 7 ) class
Obtains the fully qualified
+name
1 ); for the specified column.
61
62
// return Class object that represents className
63
r e t u r n Class.forName( className );
}
64
Loads the class definition for the class and
returns the corresponding Class object.
// end try
c a t c h ( Exception exception )
65
{
66
excepti
67
}
68
on.printStackTrace();
// end catch
69
r e t u r n Object. c l a s s ; // if problems occur above, assume type Object
70
71
}
// end method getColumnClass
Returns the
default type.
72
73
// get number of columns in ResultSet
74
public
75
int
getColu mnCount() t h r o w s IllegalStateException
{
76
// ensure database connection is available
77
if
78
79
( !connectedToDatabase )
t h r o w n e w IllegalStateException(
Override
methodtogetColumnCount
to
"Not Connected
Database" ) ;
obtain the number of columns in the
model’s underlying ResultSet
© 1992-2007 Pearson Education, Inc. All rights reserved.
80
// determine number of columns
81
try
{
82
return
83
}
84
Obtains the number of
columns in the ResultSet.
metaData.getColumnCount();
// end try
c a t c h ( SQLException sqlException )
85
ResultSetTable
Model.java
{
86
sqlException.printStackTrace();
87
}
88
// end catch
(4 of 7 )
89
r e t u r n 0; // if problems occur above, return 0 for number of columns
90
91
Outline
80
}
// end method getColumnCount
92
93
// get name of a particular column in ResultSet
94
public
95
String getColumnName( int co lumn ) t h r o w s IllegalStateException
{
96
// ensure database connection is available
97
if
( !connectedToDatabase )
t h r o w n e w IllegalStateException(
98
99
// determine col
100
try
101
102
return
}
// end try
Obtains the column name
from the ResultSet.
{
sqlException.printStackTrace();
107
108
metaData.getColumnName( column +1 );
c a t c h ( SQLException sqlException )
105
106
to obtain the name of the column in
the model’s underlying ResultSet
{
103
104
umn name
method
getColumnName
"NotOverride
Connected
to Database"
);
}
// end catch
109
© 1992-2007 Pearson Education, Inc. All rights reserved.
r e t u r n "" ; // if problems, return empty string for column name
110
111
}
// end method getColumnName
Outline
112
113
// return number of rows in ResultSet
114
public
115
int
getRowCount() t h r o w s IllegalStateException
{
if
117
( !connectedToDatabase )
Override
method
getColumnCount
t h r o w n e w IllegalStateException(
"Not
Connected
to Database" ) ;to
118
obtain the number of rows in the
model’s underlying ResultSet
119
return
120
121
ResultSetTable
Model.java
// ensure database connection is available
116
}
81
numberOfRows;
(5 of 7 )
// end method getRowCount
122
123
// obtain value in particular row and column
124
public
int
row,
int
column )
t h r o w s IllegalStateException
125
126
Object getValueAt(
{
// ensure database connectionOverride
is available
method
127
if
128
getValueAt to obtain the
Object in a particular row and column of the
IllegalStateException(
"Not Connected to Database" );
model’s underlying ResultSet
( !connectedToDatabase )
throw new
129
130
131
// obtain a value at specified ResultSet row and column
132
try
133
{
134
resultSet.absolute( row + 1 );
135
r e t u r n resu ltSet.getObject( column + 1 );
136
}
Uses ResultSet method absolute to position
the ResultSet cursor at a specific row.
// end try
Uses ResultSet method getObject
to obtain the Object in a specific
column of the current row.
© 1992-2007 Pearson Education, Inc. All rights reserved.
c a t c h ( SQLException sqlException )
137
{
138
Outline
sqlException.printStackTrace();
139
}
140
82
// end catch
141
r e t u r n "" ; // if problems, return empty string object
142
143
}
ResultSetTable
Model.java
// end method getValueAt
144
145
// set new database query string
146
public
t h r o w s SQLException, IllegalStateException
147
148
(6 of 7 )
v o i d setQuery( String query )
{
149
// ensure database connection is available
150
if
( !connectedToDatabase )
t h r o w n e w IllegalStateException(
151
"Not Connected to Database" );
152
// specify query and execute it
153
Executes the query to
obtain a new ResultSet.
resultSet = statement.executeQuery( query );
154
155
// obtain meta data for ResultSet
156
met aData
157
=
resultSet.getMetaData();
158
159
// determine number of rows in ResultSet
160
resultSet.last();
// move to last row
numberOfRows = resultSet.getRow();
161
Uses ResultSet method last to
position the ResultSet cursor at
the last row in the ResultSet.
// get row number
162
163
// notify JTable
164
fireTableStructureChanged();
165
166
}
that model has changed
// end method setQuery
Uses ResultSet method getRow
Invokes
methodthe
fireTableAStructureChanged
to obtain
row number for the
to notify
any row
JTable
using
this
current
in the
ResultSet.
ResultSetTableModel object as its model that
the structure
of the model
hasEducation,
changed.Inc. All rights reserved.
© 1992-2007
Pearson
167
// close Statement and Connection
168
public
169
{
170
if
171
{
v o i d disconnectFromDatabase()
Verify whether the connection
is already terminated
Method disconnectFromDatabase
Statement and Connection
implement an appropriate termination method
for class ResultSetTableModel
( connectedToDatabase )
172
// close
173
try
174
{
175
r e s u l t S et.close();
176
statement.close();
177
connection.close();
} // end try
179
c a t c h ( SQLException s qlException )
180
{
sqlException.printStackTrace();
181
182
} // end catch
183
finally
184
{
186
187
ResultSetTable
Model.java
Close the Statement and Connection
if a7 )
(7 of
ResultSetTableModel object is garbage collected.
178
185
Outline
83
// update database connection
connectedToDatabase
= false ;
} // end finally
} // end if
188
} // end method disconnectFromDatabase
189 }
// end class ResultSetTableModel
status
Set connectedToDatabase to false to
ensure that clients do not use an instance of
ResultSetTableModel after that instance
has already been terminated
© 1992-2007 Pearson Education, Inc. All rights reserved.
84
ResultSet static
type constant
Description
TYPE_FORWARD_ONLY
Specifies that a ResultSet ’s cursor can move only in the forward
direction (i.e., from the first row to the last row in the
ResultSet ).
TYPE_SCROLL_INSENSITIVE
Specifies that a ResultSet ’s cursor can scroll in either direction
and that the changes made to the
ResultSet during ResultSet
processing are not reflected in the
ResultSet unless the program
queries the database again.
TYPE_SCROLL_SENSITIVE
Specifies that a ResultSet ’s cursor can scroll in either direction
and that the changes made to the
ResultSet during ResultSet !
processing are reflected immediately in the
ResultSet .!
Fig. 25.26 | ResultSet constants for specifying ResultSet type.
© 1992-2007 Pearson Education, Inc. All rights reserved.
85
Portability Tip 25.3
Some JDBC drivers do not support
scrollable ResultSets. In such cases, the
driver typically returns a ResultSet in
which the cursor can move only forward.
For more information, see your database
driver documentation.
© 1992-2007 Pearson Education, Inc. All rights reserved.
86
Portability Tip 25.4
Some JDBC drivers do not support updatable
ResultSets. In such cases, the driver
typically returns a read-only ResultSet. For
more information, see your database driver
documentation.
© 1992-2007 Pearson Education, Inc. All rights reserved.
87
Common Programming Error 25.11
Attempting to update a ResultSet when the
database driver does not support updatable
ResultSets causes
SQLFeatureNotSupportedExceptions.
© 1992-2007 Pearson Education, Inc. All rights reserved.
88
Common Programming Error 25.12
Attempting to move the cursor backward
through a ResultSet when the database
driver does not support backward
scrolling causes a SQLException.
© 1992-2007 Pearson Education, Inc. All rights reserved.
89
ResultSet static
concurrency constant
Description
CONCUR_READ_ONLY
Specifies that a ResultSet cannot be updated (i.e., changes to the
ResultSet
contents cannot be reflected in the database with
ResultSet ’s update methods).
CONCUR_UPDATABLE
Specifies that a ! ResultSet can be updated (i.e., changes to the
! ResultSet !
contents can be reflected in the database with
! ResultSet ’s update methods). !
Fig. 25.27 | ResultSet constants for specifying result properties.
© 1992-2007 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.28: DisplayQueryResults.java
2
// Display the contents of the Authors table in the books database.
3
import
java.awt.BorderLayout;
4
import
java.awt.event.ActionListener;
5
import
java.awt.event.ActionEvent;
6
import
java.awt.event. W i n d o w A d a p t e r ;
7
import
java.awt.event.WindowEvent;
8
import
java.sql.SQLException;
9
import
java.util.regex.PatternSyntaxException;
10 i m p o r t
javax.swing.JFrame;
11 i m p o r t
javax.swing.JTextArea;
12 i m p o r t
javax.swing.JScrollPane;
Outline
90
DisplayQuery
Results.java
(1 of 8 )
13 i m p o r t j a v a x . s w i n g . S c r o l l P a n e C o n s t a n t s ;
14 i m p o r t
javax.swing.JTable;
15 i m p o r t
javax.swing.JOptionPane;
16 i m p o r t
javax.swing.JButton;
17 i m p o r t
javax.swing.Box;
18 i m p o r t
javax.swing.JLabel;
19 i m p o r t
javax.swing.JTextField;
20 i m p o r t
javax.swing.R owFilter;
21 i m p o r t
javax.swing.table.TableRowSorter;
22 i m p o r t javax.swing.table.TableModel;
23
24 public class
DisplayQueryResults
e x t e n d s JFrame
25 {
26
// JDBC database URL, username and password
27
static final
Str ing D R I V E R = "com.mysql.jdbc.Driver" ;
28
static final
String
D A T A B A S E _ U R=L " j d b c : m y s q l : / / l o c a l h o s t / b o o k s " ;
29
static final
String
USERNAME = "jhtp7" ;
30
static final
String
PASSWORD= "jhtp7" ;
Declare the database driver
class name, database URL,
username and password for
accessing
the database
© 1992-2007 Pearson
Education,
Inc. All rights reserved.
31
32
// default query retrieves all data from authors table
33
static final
String
DEFAULT_QUERY
= "SELECT * FROM authors";
34
35
private
ResultSetTableModel
36
private
JTextArea queryArea;
37
// cr eate ResultSetTableModel and GUI
39
public
40
Results.java
DisplayQueryResults()
(2 of 8 )
{
s u p e r( "Displaying Query Results"
41
Declare the default query
Declare tableModel to be a reference to
ResultSetTableModel
DisplayQuery
tableModel;
38
Outline
91
);
42
// create ResultSetTableModel and display database table
43
try
44
45
{
46
// create TableModel for results of query SELECT * FROM authors
47
tableModel =
48
n e w ResultSetTableModel(
D R I V E R, D A T A B A S E _ U,R L
U S E R N A M, E P A S S W O R, DDEFAULT_QUERY
);
49
50
// set up JText
51
queryArea =
52
53
Area in which user types queries
n e w JTextArea(
queryArea.setWrapStyleWord(
queryArea.setLineWrap(
Create TableModel
for results of default
query “SELECT *
FROM authors”
DEFAULT_QUERY
, 3, 100 );
t r u e );
t r u e );
54
55
JScrollPane scrollPane =
n e w JScr ollPane(
queryArea,
56
ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED
,
57
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER
);
58
59
60
// set up JButton for submitting queries
JButton submitBut
ton = n e w JButton(
"Submit Query"
);
© 1992-2007 Pearson Education, Inc. All rights reserved.
61
62
63
64
// create Box to manage placement of queryArea and
Outline
// submitButton in GUI
Box boxNorth = Box.createHorizontalBox();
65
boxNorth.add( scrollPane );
66
boxNorth.add( submitButton );
DisplayQuery
Results.java
67
68
// create JTable delegate for tableModel
69
JTable resultTable =
Create JTable delegate
for tableModel (3 of 8 )
n e w JTable( tableModel );
70
71
72
73
74
92
JLabel filterLabel =
final
n e w JLabel(
JTextField filterText =
JButton filterButton =
"Filter:"
);
n e w JTextField( ) ;
n e w JButton(
"Apply Filter"
);
Box boxSouth = boxNorth.createHorizontalBox();
75
76
boxSouth.add( filterLabel );
77
boxSouth.add( filterText );
78
boxSouth.a
dd( filterButton );
79
80
81
82
83
// place GUI components on content pane
add( boxNorth,
add(
B o r d e r L a y o u t . N O R T H);
n e w JScrollPane( resultTable ),
add( boxSouth,
B o r d e r L a y o u t . C E N T E R );
B o r d e r L a y o u t .S O U T H);
84
85
// create event listener for submitButton
86
submitButton.addActionListener(
87
© 1992-2007 Pearson Education, Inc. All rights reserved.
n e w ActionListener()
88
89
// pass query to table model
90
public void
91
92
// perform a new query
{
tableModel.setQuery(
96
}
queryArea.getText()
);
(4 of 8 )
// end try
c a t c h ( SQLException sqlException )
98
99
DisplayQuery
Results.java
try
94
97
actionPerformed( ActionEvent event )
93
{
93
95
Register an event handler for the
submitButton thatOutline
the user clicks
to submit a query to the database
{
{
JOptionPane.showMessageDialog(
100
sqlException.getMessage(),
101
null ,
"Database
Invoke ResultSetTableModel
method setQuery to execute
error",
the new query
JOptionPane.ERROR_MESSAGE
);
102
103
104
// try to recover from inv
105
// by executing default query
try
106
107
{
tableModel.setQuery(
108
queryArea.setText(
109
110
}
DEFAULT_QUERY
);
D E F AUL T _QUERY);
// end try
c a t c h ( SQLException sqlException2 )
111
112
alid user query
{
113
JOptionPane.showMessageDialog(
null ,
114
sqlExcep
"Database
115
tion2.getMessage(),
error",
JOptionPane.ERROR_MESSAGE
);
116
© 1992-2007 Pearson Education, Inc. All rights reserved.
117
// ensure database connection is closed
118
tableModel.disconnectFromDatabase();
119
System.exit(
120
}
121
125
DisplayQuery
Results.java
// end actionPerformed
}
124
// terminate application
// end outer catch
}
123
// end ActionListener inner class
);
// end call to addActionListener
(5 of 8 )
126
127
final
129
TableRowSorter< TableModel > sorter =
n e w TableRowSorter< TableModel >( tableModel );
128
94
// end inner catch
}
122
1 );
Ensure that the database
connection is Outline
closed
Set up TableRowSorter
resultTable.setRowSorter( sorter );
130
setSize(
500, 250 );
131
setVisible(
t r u e );
// set window si z e
// display window
132
133
134
// create listener for filterButton
filterButton.addActionListener(
n e w ActionListener()
135
136
{
// pass filter text to listener
137
public void
138
139
actionPerformed( ActionEvent e )
{
String text = filterText.getText();
140
141
if
142
sorter.setRowFilter(
143
146
0 )
null
);
No filter initially
else
144
145
( text.length() ==
{
try
© 1992-2007 Pearson Education, Inc. All rights reserved.
{
147
sorter.setRowFilter(
148
Outline
Set filter using
regular
expression
RowFilter.regexFilter( text ) );
149
}
150
// end try
c a t c h ( PatternSyntaxExceptio n pse )
151
{
152
JOptionPane.showMessageDialog(
153
null ,
154
"Bad regex pattern" , "Bad regex pattern" ,
155
JOptionPane.ERROR_MESSAGE
);
}
156
}
157
}
158
}
159
);
160
161
}
DisplayQuery
Results.java
(6 of 8 )
// end catch
// end else
// end method actionPerfomed
// end annonymous inner class
// end call to addActionLister
// end try
c at c h ( ClassNotFoundException classNotFound )
162
163
95
{
JOptionPane.showMessageDialog(
164
null ,
165
"Database Driver not found" , "Driver not found" ,
166
JOptionPane.ERROR_MESSAGE
);
167
System.exit(
168
169
}
1 );
// terminate application
// end catch
© 1992-2007 Pearson Education, Inc. All rights reserved.
c a t c h ( SQLException sqlException )
170
{
171
JOptionPane.showMessageDialog(
172
"Database
173
null ,
sqlException.getMessage(),
Outline
96
error", JOptionPane.ERROR_MESSAGE
);
174
175
// ensure database connection is closed
176
tableModel.disconnectFromDatabase();
177
System.exit(
178
}
179
1 );
Ensure that the database
connection is closed
// terminate application
DisplayQuery
Results.java
(7 of 8 )
// end catch
180
181
// dispose of window when user quits applicatio
182
// the default of HIDE_ON_CLOSE)
183
setDefaultCloseOperation(
n (this overrides
D I S P O S E _ O N _ C L O S);E
184
185
// ensure database connection is closed when user quits application
186
addWindowListener(
187
n e w WindowAdapter()
188
{
189
190
// disconnect from database and exit when window has closed
191
public void
192
{
windowClosed( WindowEvent event )
193
tableModel.disconnectFromDatabase();
194
System.exit(
195
196
}
);
197
198
}
0 );
} // end method windowClosed
// en d WindowAdapter inner class
Ensure that the database
connection is closed
when window is closed
// end call to addWindowListener
// end DisplayQueryResults constructor
199
© 1992-2007 Pearson Education, Inc. All rights reserved.
200
// execute application
201
public static void
202
{
Outline
97
n e w DisplayQueryResults();
203
204
main( String args[] )
}
// end main
205 } // end class DisplayQueryResults
DisplayQuery
Results.java
(8 of 8 )
© 1992-2007 Pearson Education, Inc. All rights reserved.
98
25.10 RowSet Interface
• Interface RowSet
– Configures the database connection automatically
– Prepares query statements automatically
– Provides set methods to specify the properties needed to establish
a connection
– Part of the javax.sql package
• Two types of RowSet
– Connected RowSet
• Connects to database once and remain connected
– Disconnected RowSet
• Connects to database, executes a query and then closes connection
© 2005 Pearson Education, Inc. All rights reserved.
99
25.10 RowSet Interface (Cont.)
• Package javax.sql.rowset
– JdbcRowSet
• Connected RowSet
• Wrapper around a ResultSet
• Scrollable and updatable by default
– CachedRowSet
Disconnected RowSet
Cache the data of ResultSet in memory
Scrollable and updatable by default
Serializable
– Can be passed between Java application
• Limitation
– Amount of data that can be stored in memory is limited
•
•
•
•
© 2005 Pearson Education, Inc. All rights reserved.
100
Portability Tip 25.5
A RowSet can provide scrolling
capability for drivers that do not
support scrollable ResultSets.
© 1992-2007 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.29: JdbcRowSetTest.java
2
// Displaying the contents of the authors table using JdbcRowSet.
3
import
java.sql.ResultSetMetaData;
4
import
java.sql.SQLException;
5
i m p o r t javax.sql.rowset.JdbcRowSet;
6
import
com.sun.rowset.JdbcRowSetImpl;
// Sun's JdbcRowSet implementation
7
8
public class
9
{
10
JdbcRowSetTest
Outline
101
JdbcRowSetTest
.java
(1 of 3 )
// JDBC driver name and database URL
11
static final
String
D R I V E R = "com.mysql.jdbc.Driver" ;
12
static final
String
D A TA B A S E _ U R L
= "jdbc:mysql://localhost/books" ;
13
static final
String
U S E R N A M E= "jhtp7" ;
14
static final
String
PASSWORD
= "jhtp7" ;
15
// constructor connects to database, queries database, processes
16
17
// results and displays r
18
public
19
// connect to database books and query database
try
21
23
JdbcRowSetTest()
{
20
22
esults in window
{
Class.forName(
D R I V E R );
24
© 1992-2007 Pearson Education, Inc. All rights reserved.
25
// specify properties of JdbcRowSet
26
JdbcRowSet rowSet = n e w JdbcRowSetImpl();
Use Sun’s reference
Outline
Invoke JdbcRowSet method setUrl
rowSet.setUrl(
D A T A B A S E _ U R);L // set database URL implementation of JdbcRowSet
Invoke
JdbcRowSet
method
to
specify
the database
URL
rowSet.setUsername( U S E RN A M E); // set username
interface
(JdbcRowSetImpl)
to
Invoke
JdbcRowSet
method
setUsername
to
specify
the
username
rowSet.setPassword( P A S S W O R );
D // set password
JdbcRowSet
method
createInvoke
a JdbcRowSet
object
rowSet.setCommand( "SELECT * FROM authors" setUsername
); // set queryto specify the password
setCommand
to JdbcRowSetTest
specify the query
Invoke JdbcRowSet
method
rowSet.execute();
// execute query
execute to execute the query.java
27
28
29
30
31
32
// process query results
33
34
ResultSetMetaData
35
int
metaData
numberOfColumns
System.out.println(
36
=
=
rowSet.getMetaData();
102
(2 of 3 )
metaData.getColumnCount();
"Authors Table of Books Database:\n" );
37
// display rowset header
38
f o r ( int i =
39
1; i <= numberOfColumns; i++ )
40
System.out.printf(
41
System.out.println();
" %- 8 s\t " , metaData.getColumnName( i ) );
42
// display each row
43
while
44
( rowSet.next() )
{
45
f o r ( int i =
46
1; i <= numberOfColumns; i++ )
47
System.out.printf(
48
System.out.println();
}
49
" %- 8 s\t " , rowSet.getObject( i ) );
// end whil e
50
51
// close the underlying ResultSet, Statement and Connection
52
rowSet.close();
53
}
// end try
© 1992-2007 Pearson Education, Inc. All rights reserved.
c a t c h ( SQLException sqlException )
54
{
55
sqlException.printStackTrace();
56
System.exit(
57
}
58
// end catch
{
60
61
classN
62
System.exit(
}
63
64
1 );
c a t c h ( ClassNotFoundException classNotFound )
59
}
Outline
103
otFound.printStackTrace();
1 );
JdbcRowSetTest
.java
(3 of 3 )
// end catch
// end DisplayAuthors constructor
65
66
// launch the application
67
public static void
68
args[] )
{
JdbcRowSetTest application =
69
70
main( String
}
n e w JdbcRowSetTest();
// end main
71 } // end class JdbcRowSetTest
Authors Table of Books Database:
authorID
1
2
3
4
firstName
Harvey
Paul
Andrew
David
lastName
Deitel
Deitel
Goldberg
Choffnes
© 1992-2007 Pearson Education, Inc. All rights reserved.
104
25.11 Java DB/Apache Derby
• As of JDK 6, Sun Microsystems now bundles the
open-source, pure Java database Java DB (the
Sun branded version of Apache Derby) with the
JDK
• We use the embedded version of Java DB
• There is also a network version that executes
similarly to the MySQL DBMS introduced earlier
in the chapter
© 2005 Pearson Education, Inc. All rights reserved.
105
25.11 Java DB/Apache Derby
• Java DB comes with several batch files to configure and run it
• First set the environment variable JAVA_HOME to refer to the JDK’s
C:\Program Files\Java\jdk1.6.0 installation directory
• Open the batch file setEmbeddedCP.bat (located in C:\Program
Files\Java\jdk1.6.0\db\frameworks\embedded\bin) in a text editor such
as Notepad
• Locate the line
rem set DERBY_INSTALL=
and change it to
set DERBY_INSTALL=C:\Program Files\Java\jdk1.6.0\db
• Also, comment out the line
@FOR %%X in ("%DERBY_HOME%") DO SET DERBY_HOME=%%~sX
by preceding it with REM
• Save your changes and close this file
© 2005 Pearson Education, Inc. All rights reserved.
106
25.11 Java DB/Apache Derby
• Change directories to C:\Program Files\Java\
jdk1.6.0\db\frameworks\embedded\bin\. Then, type
setEmbeddedCP.bat and press Enter to set the
environment variables required by Java DB.
• Embedded Java DB database must reside in the same
location as the application that manipulates the database
– Change to the directory that contains the code for Figs.
25.30–25.32
• Execute the command
"C:\Program Files\Java\jdk1.6.0\db\frameworks\embedded\bin\ij"
to start the command-line tool for interacting with Java
DB. The double quotes are necessary because the path
contains a space.
© 2005 Pearson Education, Inc. All rights reserved.
107
25.11 Java DB/Apache Derby
• At the ij> prompt type
connect 'jdbc:derby:AddressBook;create=true;
user=jhtp7;password=jhtp7';
to create the AddressBook database in the current
directory. This command also creates the user jhtp7 with
the password jhtp7 for accessing the database.
• To create the database table and insert sample data in the
database type
run 'address.sql';
• To terminate the Java DB command-line tool, type
exit;
© 2005 Pearson Education, Inc. All rights reserved.
108
25.12 PreparedStatements
• PreparedStatements execute more efficiently
than Statement objects
• PreparedStatements can specify parameters
© 2005 Pearson Education, Inc. All rights reserved.
109
25.12 PreparedStatements
• PreparedStatement to locate all book titles for an
author with a specific last name and first name, and to
execute that query for several authors:
– PreparedStatement authorBooks =
connection.prepareStatement(
"SELECT lastName, firstName, title " +
"FROM authors INNER JOIN authorISBN " +
"ON authors.authorID=authorISBN.authorID " +
"INNER JOIN titles " +
"ON authorISBN.isbn=titles.isbn " +
"WHERE lastName = ? AND firstName = ?" );
• Question marks (?) are placeholders for values that will
be passed as part of the query to the database
© 2005 Pearson Education, Inc. All rights reserved.
110
25.12 PreparedStatements
• Program must specify the parameter values by using the
PreparedStatement interface’s set methods.
• For the preceding query, both parameters are strings that
can be set with PreparedStatement method setString
as follows:
authorBooks.setString( 1, "Deitel" );
authorBooks.setString( 2, "Paul" );
• setString automatically escapes String parameter values
as necessary (e.g., the quote in the name O’Brien)
• More info at java.sun.com/javase/6/docs/api/
java/sql/PreparedStatement.html
© 2005 Pearson Education, Inc. All rights reserved.
111
Performance Tip 25.2
PreparedStatements are more efficient
than Statements when executing SQL
statements multiple times and with
different parameter values.
© 1992-2007 Pearson Education, Inc. All rights reserved.
112
Error-Prevention Tip 25.1
Use PreparedStatements with
parameters for queries that receive
String values as arguments to ensure
that the Strings are quoted properly in
the SQL statement.
© 1992-2007 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.30: Person.java
2
// Person class that represents an entry in an address book.
3
public class
4
{
Person
5
private int
6
private
String firstName;
7
private
String lastName;
8
private
String email;
9
private
String phoneNumber;
Outline
113
addressID;
Person.java
(1 of 3 )
10
11
12
// no - argument
public
13
{
14
}
constructor
Person()
// end no- argument
Person
constructor
15
16
// constructor
17
public
String
18
19
Person(
int
id, String first, String last,
emailAddress, String phone )
{
20
setAddressID( id );
21
setFirstName( first );
22
setLastName( last );
23
setEmail( emailAddress );
24
setPhoneNumber( phone );
25
}
// end five - argument
Person
constructor
26
© 1992-2007 Pearson Education, Inc. All rights reserved.
27
// sets the addressID
28
public void
29
int id )
{
}
// end method setAddressID
32
33
// returns the addressID
34
public int
35
getAddressID()
{
return
36
37
Outline
114
addressID = id;
30
31
setAddressID(
}
Person.java
(2 of 3 )
addressID;
// end method getAddressID
38
39
// sets the firstName
40
public void
41
{
firstName = first;
42
43
setFirstName( String first )
}
// end method setFirstName
44
45
// returns the first name
46
public
47
{
return
48
49
String getFirstName()
}
firstName;
// end method getFirstName
50
51
// sets the lastName
52
public void
53
{
lastName = last;
54
55
setLastName( String last )
}
// end method setLastName
56
© 1992-2007 Pearson Education, Inc. All rights reserved.
57
// returns the first name
58
public
59
{
return
60
61
String getLastName()
}
lastName;
// end method getLastName
62
63
// sets the email address
64
public void
65
setEmail( String emailAddress )
{
Person.java
(3 of 3 )
email = emailAddress;
66
67
Outline
115
}
// end method setEmail
68
69
// returns the email address
70
public
71
{
r e t u r n email;
72
73
String getEmail()
}
// end method getEmail
74
75
// sets the phone number
76
public void
77
{
phoneNumber = phone;
78
79
setPhoneNumber( String phone )
}
// end method setPhoneNumber
80
81
// returns the email address
82
public
83
{
return
84
85
String getPhoneNumber()
}
phoneNumber;
// end method getPhoneNumber
86 } // end class Person
© 1992-2007 Pearson Education, Inc. All rights reserved.
1
// Fig. 25.31: PersonQueries.java
2
// PreparedStatements used by the Address Book application
3
import
java.sql.Connection;
4
import
java.sql.DriverManager;
5
import
java.sql.PreparedStatement;
6
import
java.sql.ResultSet;
7
i m p o r t java.sql .SQLException;
8
i m p o r t java.util.List;
9
import
Outline
All program to use
PreparedStatements
116
PersonQueries .java
(1 of 7 )
java.util.ArrayList;
10
11 public class
PersonQueries
12 {
13
private static final
String
U R L = " j d b c : d e r b y : A d d r e s s B o o k ";
14
private static final
String
USERNAME
= "jhtp7" ;
15
p r i v ate static final
String
P A S S W O R=
D "jhtp7" ;
16
17
p r i v a t e Connection connection =
null ; // manages connection
18
private
PreparedStatement selectAllPeople =
19
private
PreparedStatement selectPeopleByLastName = null ;
20
private
PreparedStatement insertNewPerson = null ;
null ;
Declare
PreparedStatements
21
22
// constructor
23
public
24
{
try
25
26
27
28
29
PersonQueries()
{
Note that we do not load the
Java DB driver first. JDBC
connection =
4’s automatic
DriverManager.getConnection(
U R L, driver
U S E R N A M, E P A S S W ODR );
discovery is used here.
© 1992-2007 Pearson Education, Inc. All rights reserved.
30
// create query that selects all entries in the AddressBook
31
selectAllPeople =
connection.prepareStatement(
32
"SELECT * FROM Addresses");
Outline
117
33
34
// create query that selects entries with a specific last name
35
selectPeopleByLastName = connection.prepareStatement(
36
"SELECT * FROM Addresses WHERE LastName = ?"
);
PersonQueries .java
37
38
// create ins ert that adds a new entry into the database
39
insertNewPerson = connection.prepareStatement(
40
"INSERT INTO Addresses " +
41
"( FirstName, LastName, Email, PhoneNumber ) "
42
"VALUES ( ?, ?, ?, ? )"
}
43
// end try
c a t c h ( SQLException sqlException )
44
Configure each
PreparedStatement. Each ?
represents a parameter.
{
45
sqlException.printStackTrace();
46
System.exit(
47
}
48
49
);
+
(2 of 7 )
}
1 );
// end catch
// end PersonQueries constructor
50
51
// select all of the addresses in the database
52
public
53
List< Person > getAllPeople()
{
54
List< Person > results =
55
ResultSet resultSet =
null ;
null ;
56
© 1992-2007 Pearson Education, Inc. All rights reserved.
try
57
58
{
59
// executeQuery returns ResultSet containing matching entries
60
resultSet = selectAllPeople.executeQuery();
results =
61
n e w ArrayList< Person >();
62
while
63
( resultSet.next() )
{
64
results.add(
65
" a d d r e s s I D " ),
67
resultSet.getString(
68
resultSet.getString(
" l a s t N a m e " ),
69
resultSet.getString(
"email" ),
70
resultSet.getString(
"phoneNumber" ) ) );
}
71
72
}
{
sqlException.print
}
// end catch
{
try
79
80
{
resultSet.close();
81
82
StackTrace();
finally
77
78
// end while
// end try
75
76
"firstName" ),
c a t c h ( SQLException sqlException )
73
74
Executes the query in
PreparedStatement
selectAllPeople.
PersonQueries .java
(3 of 7 )
Process the ResultSet.
n e w Person(
resultSet.getInt(
66
Outline
118
}
// end try
© 1992-2007 Pearson Education, Inc. All rights reserved.
c a t c h ( SQLException sqlException )
83
{
84
Outline
sqlException.printStackTrace();
85
close();
86
}
87
}
88
// end catch
// end finally
PersonQueries .java
89
return
90
91
119
}
results;
(4 of 7 )
// end method getAllPeople
92
// select person by last name
93
94
95
96
public
List< Person > getPeopleByLastName( String name )
{
97
List< Person > results =
98
ResultSet resultSet =
null ;
null ;
99
try
100
101
102
{
selectPeopleByLastName.setString(
1, name );
103
104
// executeQuery returns ResultSet containing matching
105
resultSet = selectPeopleByLastName.executeQuery();
106
107
results =
n e w ArrayList< Person >();
Specify the parameter to
PreparedStatement
selectPeopleByLastName.
entries
Executes the query in
PreparedStatement
selectPeopleByLastName.
// specify last name
108
© 1992-2007 Pearson Education, Inc. All rights reserved.
while
109
( resultSet.next() )
Process the ResultSet.
{
110
results.add(
111
n e w Person(
resultSet.getInt(
112
" a d d r e s s I D " ),
113
resultSet.getString(
"firs t N a m e " ),
114
resultSet.getString(
" l a s t N a m e " ),
115
resultSet.getString(
"email"
116
resultSet.getString(
"phoneNumber") ) );
}
117
}
118
Outline
120
// end while
),
PersonQueries .java
(5 of 7 )
// end try
c a t c h ( SQLException sqlException )
119
{
120
sqlException.printStackTrace();
121
}
122
// end catch
finally
123
{
124
try
125
{
126
resultSet.close();
127
}
128
// end try
c a t c h ( SQLException sqlException )
129
{
130
sqlException.printStackTrace();
131
close();
132
}
133
}
134
// end catch
// end finally
135
return
136
137
}
results;
// end method getPeopleByName
138
© 1992-2007 Pearson Education, Inc. All rights reserved.
139
// add an entry
140
public int
String fname, String lname, String email, String num )
141
142
addPerson(
{
int
143
result =
0;
144
// set parameters, then execute insertNewPerson
145
try
146
147
insertNewPerson.setString(
1, fname );
149
insertNewPerson.setString(
2, lname );
150
insertNewPerson.setString(
3, email );
151
insertNewPerson.setString(
4, num );
152
153
// inser t the new entry; returns # of rows updated
154
result = insertNewPerson.executeUpdate();
}
157
Specify the parameters to
PreparedStatement
insertNewPerson.
Executes the insert operation in
PreparedStatement
insertNewPerson.
{
sqlException.printStackTrace();
158
close();
159
160
// end try
c a t c h ( SQLException sqlException )
156
PersonQueries .java
(6 of 7 )
{
148
155
Outline
121
}
// end catch
© 1992-2007 Pearson Education, Inc. All rights reserved.
161
r e t u r n result;
162
163
}
// end method addPerson
Outline
122
164
165
// close the database connection
166
public void
167
{
try
168
PersonQueries .java
(7 of 7 )
{
169
connection.close();
170
}
171
// end try
c a t c h ( SQLException sqlException )
172
{
173
sqlException.printStackTrace();
174
}
175
176
close()
}
// end catch
// end method close
177 } // end interface PersonQueries
© 1992-2007 Pearson Education, Inc. All rights reserved.
1
//
Fig.
25.32:
AddressBookDisplay.java
2
// A simple address book
3
import
java.awt.event.ActionEvent;
4
import
java.awt.event.ActionListener;
5
import
java.awt.event.WindowAdapter;
6
import
java.awt.event.WindowEvent;
7
import
java.awt.Flow L a y o u t ;
8
import
java.awt.GridLayout;
9
i m p o r t java.util.List;
Outline
123
AddressBook
Display.java
(1 of 14 )
10 i m p o r t
javax.swing.JButton;
11 i m p o r t
javax.swing.Box;
12 i m p o r t
javax.swing.JFrame;
13 i m p o r t
javax.swing.JLabel;
14 i m p o r t
javax.swing.JPanel;
15 i m p o r t
javax.swing.JTextF ield;
16 i m p o r t
javax.swing.WindowConstants;
17 i m p o r t
javax.swing.BoxLayout;
18 i m p o r t
javax.swing.BorderFactory;
19 i m p o r t
javax.swing.JOptionPane;
20
21 public class
AddressBookDisplay e x t e n d s JFrame
22 {
23
private
Person currentEnt r y ;
24
private
PersonQueries
25
p r i v a t e List< Person > results;
26
private int
numberOfEntries =
27
private int
currentEntryIndex;
personQueries;
0;
28
29
private
JButton browseButton;
30
private
JLabel emailLabel;
© 1992-2007 Pearson Education, Inc. All rights reserved.
31
private
JTextField emailTextField;
32
private
JLabel firstNameLabel;
33
private
JTextField firstNameTextField;
34
private
JLabel idLabel;
35
private
JTextField idTextField;
36
private
JTextField indexTextField;
37
p r i v a t e JLabel lastNameLabel;
38
private
JTextField lastNameTextField;
39
private
JTextField maxTextField;
40
private
JButton nextButton;
41
private
JLabel ofLabel;
42
private
JLabel phoneLabel;
43
private
JTextField phoneTextField
44
private
JButton previousButton;
45
private
JButton queryButton;
46
private
JLabel queryLabel;
47
private
JPanel queryPanel;
48
private
JPanel navigatePanel;
49
private
JPanel displayPanel;
50
private
JTextField query
51
private
JButton insertButton;
Outline
124
AddressBook
Display.java
(2 of 14 )
;
TextField;
52
53
54
55
56
// no - argument
public
constructor
AddressBookDisplay()
{
s u p e r( "Address Book" );
57
58
// establish database connection and set up PreparedState
59
personQueries =
ments
n e w PersonQueries();
60
© 1992-2007 Pearson Education, Inc. All rights reserved.
61
// create GUI
62
navigatePanel =
63
previousButton =
n e w JButton();
64
indexTextField =
n e w JTextField(
65
ofLabel =
66
maxTextField =
67
nextButton =
68
displayPanel =
69
idLabel =
70
idTextField =
71
firstNameLabel =
72
firstNameTextField =
73
lastNameLabel =
74
lastNameTextField =
n e w JPanel();
Outline
125
2 );
n e w JLabel();
n e w JTextField(
2 );
AddressBook
Display.java
n e w JButton();
n e w JPanel();
n e w JLabel();
n e w JTextField(
(3 of 14 )
1 0 );
n e w JLabel();
n e w JTextField(
1 0 );
n e w JLabel();
n e w JTextField(
75
emailLabel =
76
emailTextField =
77
phoneLabel =
78
phoneTextField =
79
queryPanel =
n e w JPan el();
80
queryLabel =
n e w JLabel();
81
queryTextField =
82
queryButton =
83
browseButton =
n e w JButton();
84
insertButton =
n e w JButton();
1 0 );
n e w JLabel();
n e w JTextField(
1 0 );
n e w JLabel();
n e w JTextField(
n e w JTextField(
1 0 );
1 0 );
n e w JButton();
85
86
setLayout(
87
setSize(
88
n e w FlowLayout( FlowLayout.CENTER, 1 0, 1 0 ) );
400, 300 );
setResizable(
f a l s e );
89
© 1992-2007 Pearson Education, Inc. All rights reserved.
navigatePanel.setLayout(
90
n e w BoxLayout( navigatePanel,
91
B o x L a y o u t . X _ A X I S) );
92
93
previousButton.setText(
94
previousButton.setEnabled(
false
);
);
previousButton.addActionListener(
95
AddressBook
Display.java
n e w ActionListener()
96
{
97
public void
98
actionPerformed( ActionEvent evt )
{
99
(4 of 14 )
previousButtonActionPerformed( evt );
100
}
101
}
102
103
"Previous"
Outline
126
);
// end method actionPerformed
// end anonymous inner class
// end call to addActionListener
104
navigatePanel.add( previousButton );
105
navigatePanel.add( Box.createHorizontalStrut(
106
1 0 ) );
107
indexTextField.setHorizontalAlignment(
108
JTextField.CENTER );
109
indexTextField.addActionListener(
110
n e w ActionListener()
111
{
112
public void
113
{
114
indexTextFieldActionPerformed( evt );
115
}
116
}
117
118
actionPerformed( ActionEvent evt )
);
// end method actionPerformed
// end anonymous inner class
// end call to addActionListener
119
© 1992-2007 Pearson Education, Inc. All rights reserved.
navigatePanel.add( indexTextField );
120
navigatePanel.add( Box.createHorizontalStrut(
121
1 0 ) );
Outline
122
ofLabel.setText(
123
"of"
);
navigatePanel.add( ofLabel );
124
navigatePanel.add( Box.createHorizontalStrut(
125
1 0 ) );
AddressBook
Display.java
126
maxTextField.setHorizontalAlignment(
127
JTextField.CENTER );
128
maxTextField.setEditable(
129
130
127
nav igatePanel.add(
false
maxTextField
(5 of 14 )
);
);
navigatePanel.add( Box.createHorizontalStrut(
131
1 0 ) );
132
133
nextButton.setText(
134
nextButton.setEnabled(
f a l s e );
nextButton.addActionListener(
135
n e w ActionListener()
136
{
137
public void
138
actionPerformed( ActionEvent evt )
{
139
nextButtonActionPerformed( evt );
140
}
141
}
142
143
"Next" );
);
// end method actionPerformed
// end anonymous inner class
// end call to addActionListener
144
145
146
navigatePanel.add( nextButton );
add( navigatePanel );
147
148
displayPanel.setLayout(
n e w GridLayout(
5, 2, 4, 4 ) );
© 1992-2007 Pearson Education, Inc. All rights reserved.
149
150
151
idLabel.setText(
"Address ID:"
);
Outline
displayPanel.add( idLabel );
128
152
153
idTextField.setEditable(
f a l s e );
154
displayPanel.add( idTextField );
155
156
firstNameLabel.setText(
"First Name:"
157
displayPanel.add( firstNameLabel );
158
displayPanel.add( firstNameTextField );
);
AddressBook
Display.java
(6 of 14 )
159
160
lastNameLabel.setText(
"Last Name:" ) ;
161
displayPanel.add( lastNameLabel );
162
displayPanel.add( lastNameTextField );
163
164
emailLabel.setText(
"Email:"
);
165
displayPanel.add( emailLabel );
166
displayPanel.add( emailTextField );
167
168
phoneLabel.setText(
"Phone Number:" );
169
displayPanel.add( phoneLabel );
170
displayPanel.add( phoneTextField );
171
add( displayPanel );
172
173
174
queryPanel.setLayout(
n e w BoxLayout( queryPanel,
B o x L a y o u t . X _ A X I S) );
175
© 1992-2007 Pearson Education, Inc. All rights reserved.
queryPanel.setBorder( BorderFactory.createTitledBorder(
176
"Find an entry by last name"
177
queryLabel.setText(
178
) );
queryPanel.add( Box.createHorizontalStrut(
179
Outline
"Last Name:" );
5 ) );
queryPanel.add( queryLabel );
180
queryPanel.add( Box.createHorizontalStrut(
181
10 ) );
queryPanel.add( queryTextField );
182
queryPanel.add( Box.createHorizontalStrut(
183
1 0 ) );
184
queryButton.setText(
185
"Find"
AddressBook
Display.java
(7 of 14 )
);
queryButton.addActionListener(
186
n e w ActionListener()
187
{
188
public void
189
actionPerformed( ActionEvent evt )
{
190
queryButtonActionPerformed( evt );
191
}
192
}
193
194
129
);
// end method actionPerformed
// end anonymous inner class
// end call to addActionListener
195
196
197
198
queryPanel.add( queryButton );
queryPanel.add( Box.createHorizontalStrut(
5 ) );
add( queryPanel );
199
© 1992-2007 Pearson Education, Inc. All rights reserved.
browseButton.setText(
200
);
browseButton.addActionListener(
201
Outline
n e w ActionListener()
202
130
{
203
public void
204
actionPerformed( ActionEvent evt )
{
205
AddressBook
Display.java
browseButtonActionPerformed( evt );
206
}
207
}
208
209
"Browse All Entries"
);
// end
method
actionPerformed
// end anonymous inner class
(8 of 14 )
// end call to addActionListener
210
add( browseButton );
211
212
insertButton.setText(
213
);
insertButton.addActionListener(
214
n e w ActionListener()
215
{
216
public void
217
actionPerformed( ActionEvent evt )
{
218
insertButtonActionPerformed( evt );
219
}
220
}
221
222
"Insert New Entry"
);
// end method actionPerformed
// end anonymous inner class
// end call to addActionListener
223
© 1992-2007 Pearson Education, Inc. All rights reserved.
add( insertButton );
224
Outline
225
addWindowListener(
226
131
n e w WindowAdapter()
227
{
228
public void
229
windowClosing( WindowEvent evt )
{
230
personQueries.close();
231
System.exit(
232
}
233
}
234
);
235
// close database connection
0 );
AddressBook
Display.java
(9 of 14 )
// end method windowClosing
// end anonymous inner class
// end call to addWindowListener
236
setVisible(
237
238
}
t r u e );
// end no- argument
constructor
239
240
// handles call when previousButton is clicked
241
private
242
void
previousButtonActionPerformed( ActionEvent evt )
{
currentEntryIndex
243
-- ;
244
if
245
( currentEntryIndex <
0 )
currentEntryIndex = numberOfEntries
246
- 1;
247
248
indexTextField.setText(
249
indexTextFieldActionPerformed( evt );
250
}
"" + ( currentEntryIndex +
1 ) );
// end method previousButtonActionPerformed
251
© 1992-2007 Pearson Education, Inc. All rights reserved.
252
// handles call when nextButton is clicked
253
private
254
void
nextButtonActionPerformed( ActionEvent evt )
Outline
{
132
currentEntryIndex++;
255
256
if
257
( currentEntryIndex >= numberOfEntries )
currentEn
258
tryIndex =
AddressBook
Display.java
0;
259
indexTextField.setText(
260
1 ) );
(10 of 14 )
indexTextFieldActionPerformed( evt );
261
262
"" + ( currentEntryIndex +
}
// end method nextButtonActionPerformed
263
264
// handles call when queryButton is clicke
265
private
266
queryButtonActionPerformed( ActionEvent evt )
{
results =
267
personQueries.getPeopleByLastName(
268
269
void
d
queryTextField.getText()
numberO fEntries = results.size();
270
if
271
272
273
274
275
( numberOfEntries !=
0 )
{
currentEntryIndex =
0;
currentEntry = results.get( currentEntryIndex );
idTextField.setText(
""
+ currentEntry.getAdd ressID()
276
firstNameTextField.setText( currentEntry.getFirstName() );
277
lastNameTextField.setText( currentEntry.getLastName() );
278
Executes the query in
PreparedStatement
);
selectPeopleByLastName from
class PersonQueries.
);
emailTextField.setText( currentEntry.getEmail() );
279
phoneTextField.se
tText(
280
maxTextField.setText(
currentEntry.getPhoneNumber()
);
"" + numberOfEntries );
© 1992-2007 Pearson Education, Inc. All rights reserved.
281
indexTextField.setText(
282
nextButton.setEnabled(
283
previousButton.setEnabled(
}
284
1 ) );
t r u e );
Outline
t r u e );
// end if
browseButtonActionPerformed( evt );
286
}
AddressBook
Display.java
// end method queryButtonActionPerformed
288
289
// handles call when a new value is entered in indextTextField
290
private
291
133
else
285
287
"" + ( currentEntryIndex +
void
indexTextFiel
dActionPerformed( ActionEvent evt )
(11 of 14 )
{
currentEntryIndex =
292
( Integer.parseInt( indexTextField.getText() )
293
- 1 );
294
if
295
( numberOfEntries !=
0 && currentEntryIndex < numberOfEntries )
{
296
currentEntry = results.get( currentEntryIndex );
297
idTextField.setText("" + currentEntry.getAddressID() );
298
299
firstNameTextField.setText( currentEntry.getFirstName() );
300
lastNameTextField.setText( currentEntry.getLastName() );
301
emailTextField.setText( currentEntry.getEmail() );
302
phoneTextField.setText( currentEntry.getPhoneNumber() );
303
maxTextField.setText(
304
indexTextField.setText(
}
305
306
}
"" + numberOfEntries );
"" + ( currentEntryIndex +
1 ) );
// end if
// end method indexTextFieldActionPerformed
307
© 1992-2007 Pearson Education, Inc. All rights reserved.
308
// handles call when browseButton is clicked
309
private
310
void
browseButtonActionPerformed( ActionEvent evt )
Outline
{
try
311
{
312
results
313
=
personQueries.getAllPeople();
numberOfEntries = resul
314
ts.size();
315
if
316
( numberOfEntries !=
0 )
{
317
currentEntryIndex =
318
Executes the query in
PreparedStatement AddressBook
Display.java
selectAllPeople from class
PersonQueries.
(12 of 14 )
0;
currentEntry = results.get( currentEntryIndex );
319
idTextField.setText(
320
""
+
currentEntry.getAddr essID() );
321
firstNameTextField.setText( currentEntry.getFirstName() );
322
lastNameTextField.setText( currentEntry.getLastName() );
emailTextField.setText( currentEntry.getEmail() );
323
phoneT
324
extField.setText(
325
maxTextField.setText(
326
indexTextField.setText(
327
nextButton.setEnabled(
currentEntry.getPhoneNumber()
}
329
}
330
);
"" + numberOfEntries );
"" + ( currentEntryIndex +
1 ) );
t r u e );
previousButton.setEnabled(
328
t r u e );
// end if
// end try
c a t c h ( Exception e )
331
{
332
e.printStackTrace();
333
}
334
335
134
}
// end catch
// end method browseButtonActionPerformed
336
© 1992-2007 Pearson Education, Inc. All rights reserved.
337
// handles call when insertButton is clicked
338
private
339
void
insertButtonActionPerformed( ActionEvent evt )
{
int
340
result
=
personQueries.addPerson(
firstNameTextField.getText(),
341
lastNameTextField.getText() , emailTextField.getText(),
342
phoneTextField.getText() );
343
if
344
( result ==
1 )
JOptionPane.showMessageDialog(
345
t h i s , "Person
added!" ,
" P e r s o n added", JOptionPane.PLAIN_MESSAGE);
346
Outline
135
Executes the insert operation in
PreparedStatement
AddressBook
insertNewPerson
from class
Display.java
PersonQueries.
(13 of 14 )
else
347
JOptionPane.showMessageDialog(
348
t h i s , "Person not added!" ,
" E r r o r " , JOptionPane.PLAIN_MESSAGE);
349
350
browseButtonActionPerformed( evt );
351
352
}
// end method insertButtonActionPerformed
353
354
// main method
355
public static void
356
{
n e w AddressBookDisplay();
357
358
main( String args[] )
}
// end method main
359 } // end class AddressBookDisplay
© 1992-2007 Pearson Education, Inc. All rights reserved.
Outline
136
AddressBook
Display.java
(14 of 14 )
© 1992-2007 Pearson Education, Inc. All rights reserved.
137
25.12 Stored Procedures
• Stored procedures
– Store SQL statements in a database
– Invoke SQL statements by programs accessing the
database
• Interface CallableStatement
– Receive arguments
– Output parameters
© 2005 Pearson Education, Inc. All rights reserved.
138
Portability Tip 25.6
Although the syntax for creating stored
procedures differs across database
management systems, the interface
CallableStatement provides a uniform
interface for specifying input and output
parameters for stored procedures and for
invoking stored procedures.
© 1992-2007 Pearson Education, Inc. All rights reserved.
139
Portability Tip 25.7
According to the Java API documentation
for interface CallableStatement, for
maximum portability between database
systems, programs should process the update
counts or ResultSets returned from a
CallableStatement before obtaining the
values of any output parameters.
© 1992-2007 Pearson Education, Inc. All rights reserved.
140
25.13 Transaction Processing
• Many applications require guarantees that a
series of database insertions, updates and
deletions executes properly before the
applications continue processing the next
database operation
• Enables a program that interacts with a database
to treat a database operation (or set of
operations) as a single operation
– Known as an atomic operation or a transaction
– At the end of a transaction, decide to commit or roll back
© 2005 Pearson Education, Inc. All rights reserved.
141
25.13 Transaction Processing
• Committing a transaction finalizes the database
operation(s); all insertions, updates and deletions
performed as part of the transaction cannot be
reversed without performing a new database
operation
• Rolling back a transaction leaves the database in
its state prior to the database operation
© 2005 Pearson Education, Inc. All rights reserved.
142
25.13 Transaction Processing
• Methods of interface Connection
– setAutoCommit specifies whether each SQL statement
commits after it completes (a true argument) or if several
SQL statements should be grouped as a transaction (a
false argument)
• If the argument to setAutoCommit is false, the program
must follow the last SQL statement in the transaction with a
call to Connection method commit or rollback
– getAutoCommit determines the autocommit state for the
Connection.
© 2005 Pearson Education, Inc. All rights reserved.