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Java™ How to Program, 9/e
© Copyright 1992-2012 by Pearson Education, Inc. All Rights
Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

printf method PDF
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.


Package
Class
java.util
Scanner
Scanner <variable> = new Scanner( System.in );
Scanner input = new Scanner( System.in );



Strings
next( )
nextLine( )
String s;
Numbers
nextInt( )
nextDouble( )
Test for Input
hasNext( )
int x, y;
s = input.nextLine();
x = input.nextInt();
y = input.nextDouble();
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

import statement

fully qualified name (FQN)

Java hierarchy:
package
class / classes
global variables
methods
statements
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

Package java.lang
Frequently uses classes
 System
System.out, System.in, System.exit( )
 String
String name, String.format( )
 Math
Math.PI, Math.pow( ), Math.max( )
 Double
Double.parseDouble( )
 Integer
Integer.parseInt( )
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.


Operators (next slide)
 unary
- (minus sign)
 binary
=, +, -, *, /
 trinary
? : (conditional operator)
Operands
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

Expressions

Statements

Assignment
 LHS
variable
 RHS
expression
 literal
 named constant
( keyword final )
 String/Arithmetic expression
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

Rules of operator precedence
 Multiplication, division and remainder operations are applied first.
 If an expression contains several such operations, they are applied from left to
right.
 Multiplication, division and remainder operators have the same level of
precedence.
 Addition and subtraction operations are applied next.
 If an expression contains several such operations, the operators are applied
from left to right.
 Addition and subtraction operators have the same level of precedence.



When we say that operators are applied from left to right, we are
referring to their associativity.
Some operators associate from right to left.
Complete precedence chart is included in Appendix A.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.

Condition

Selection control structure
 if statement
 switch statement

Relational operators

Equality operators
(next slide)
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.
 Additional Topics (if time permits)
 Strings
 Methods
© Copyright 1992-2012 by Pearson
Education, Inc. All Rights Reserved.