Download Java Development JCreator How to run JCreator?

Java Development Process
Developing Java Programs with
• Step 1: Editing the Program
• Step 2: Compiling the Program
JCreator:
• Step 3: Running the Program
Editing, Compiling and Running
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JCreator
Java Development
• Several programs that perform different tasks used
to edit, compile and run
– Java Development Kit (JDK) – available free from
http://java.sun.com/
• Integrated Development Environments (IDE)
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–
Borland’s JBuilder
Metrowerk’s CodeWarrior
Nottingham’s CourseMarker
JCreator
• Editor with ability of colour coding.
• Automated Indention
• Code Folding
• Debugger Interface.
• More and more facilities.
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Example: Colour Coding
Correct Code
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• Easy to use.
• Word Completion
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Incorrect Code
• Powerful IDE (Integrated Development
Environment) for Java.
How to run JCreator?
• Click on ‘Start’ Menu
• Choose ‘Program’
• Find ‘JCreator’
• Click on ‘JCreator’
OR
• double click on ‘JCreator’ shortcut
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How to create a file?
Step 1: Editing the Program
• Creating a file
• Saving your file (java program)
• Java file names
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• Start writing your program.
• Save your program by pressing Ctrl+S
OR selecting ‘Save’ from ‘File’ Menu.
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Choose ‘New’ from ‘File’ Menu OR press Ctrl+N.
Click on ‘Files’ tab on ‘New’ box.
Select ‘Java File’.
Enter your file name (e.g. test).
Select the location that you want to place your program (e.g.
h:\MyProgram).
• Select ok.
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Some important issues:
• Java file names are case sensitive.
• Java programs should have .java extensions.
you don’t have to worry about that as JCreator does that
automatically for you.
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Step 2 : Compile the program
When you compile…
• Select ‘Compile File’ from ‘Build’ Menu.
OR use the shortcut.
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• The Java Compiler translates your program
into Java bytecode, which is interpreted by
the Java Virtual Machine (JVM).
• Successful compilation will create a
bytecode .class file
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After the compilation process…
• You may have no errors:
– Your program is ready to be executed. So go to step 3.
• You may have some errors:
– Go back to your program and try correct it using the
information that the JCreator compiler gives you.
– Then compile again.
– If there are no errors, go to step 3 for running your
program.
Example: Compilation Error
class test
{
public static void main(String argv [])
{
// prints "Hello World"
system.out.println("Hello World");
}
}
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system.out.println("Hello World");
^----^
*** Semantic Error: No field named "system" was found in type "test".
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Example: Compilation Error
class test
{
public static void main(String argv [])
{
// prints "Hello World"
System.out.println("Hello World")
}
}
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System.out.println("Hello World")
Example: Compilation Error
class test
{
public static void main(String argv []
{
// prints "Hello World"
System.out.println("Hello World");
}
}
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public static void main(String argv []
^-------------------------------^
*** Syntax: ";" inserted to complete BlockStatementsopt
^
*** Syntax: ) expected after this token
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Example: Compilation Error
class test
{
public static void main(String argv [])
{
/ prints "Hello World"
System.out.println("Hello World");
}
}
8.
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Example: Compilation Error
class test
{
public static void main(String argv [])
{
// prints "Hello World"
System.out.println("Hello World");
}
5. { . . .
/ prints "Hello World"
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^--------------------^
*** Syntax: Unexpected symbols ignored
}
-------->
*** Syntax: "}" inserted to complete ClassBody
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Step 3: Run your Program
Example: Run Time Error
At this stage, the JVM interprets your program, which has been loaded
into memory.
To to run your program:
• Select ‘Execute File’ from ‘Build’ Menu
OR
• Click on shortcut from toolbar.
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If you want to …
• Save your program with different name:
Select ‘Save As’ from ‘File’ menu and enter your desired file name and the
location you need to put it.
• Open an existing file:
Select ‘open’ from ‘File’ menu (or press Ctrl + O) and find your file from the
right directory.
• Copy selected lines of code somewhere else:
Highlight the code with the help of mouse or Shift + Arrow key.
Press Ctrl + C or choose ‘copy’ from ‘Edit’ Menu.
Go to the destination line.
Press Ctrl + V or select ‘paste’ from ‘Edit’ Menu.
• Move selected lines of code somewhere else:
Highlight the code with the help of mouse or Shift + Arrow key.
• Print your file:
Select ‘print’ from ‘File’ menu (or press Ctrl + P).
Press Ctrl + X or choose ‘cut’ from ‘Edit’ Menu.
Go to the destination line.
Press Ctrl + V or select ‘paste’ from ‘Edit’ Menu.
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• Undo
Press Ctrl + Z or select ‘undo’ from ‘Edit’ menu.
• Find a word(s) in file:
Press Ctrl + F or select ‘find’ from ‘Search’ menu.
Enter the word(s) you want to find.
adjust the options in Find box to your desire.
click on ‘find next’.
Common Syntax Errors
• Leaving out symbols such as:
• ;
• }
• )
• Ignore symbol ‘+’ between two literal
strings in print statement
For more shortcut look at ‘advanced’ from ‘Edit’ Menu.
For more information on JCreator look at
http://www.jcreator.com/
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• System.out.println("Hello" "World");
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Common Semantic Errors
• Failing to define a variable before it is used.
• Use of non-static variables inside a static
method.
• Type mismatch.
• Using a variable that has not been initialised
• Declaring an identifier more than once.
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