4003-707-02 Advanced Programming
Module 2. Elementary Programming -- Lecture Notes

Java Operators

• K. Arnold and J. Gosling, The Java Programming Language (Addison-Wesley, 1996), pages 102-103.

  The following table lists all the operators in order of precedence from highest to lowest. All the operators are binary, except those shown as unary with expr, the creation and cast operators (which are also unary), and the conditional operator (which is ternary). Operators with the same precedence appear on the same line of the table:

  postfix operators	[]  .  (params)  expr++  expr--
  unary operators	++expr  --expr  +expr  -expr  ~  !
  creation or cast	new  (type)expr
  multiplicative	*  /  %
  additive	+  -
  shift	<<  >>  >>>
  relational	<  >  >=  <=  instanceof
  equality	==  !=
  bitwise AND	&
  bitwise exclusive OR	^
  bitwise OR	|
  logical AND	&&
  logical OR	||
  conditional	?:
  assignment	=  +=  -=  *=  /=  %=  >>=  <<=  >>>=  &=  ^=  |=

  All binary operators other than assignment operators are left-associative. Assignment is right-associative -- in other words, a=b=c is equivalent to a=(b=c).

  Precedence can be overridden using parentheses. The expression x+y*z multiplies y by z first and then adds x, whereas (x+y)*z adds x and y first and multiplies the result by z.

Primitive Types

• K. Arnold and J. Gosling, The Java Programming Language (Addison-Wesley, 1996), page 93.

  The primitive data types of Java are:

  boolean	either true or false
  char	16-bit Unicode 1.1.5 character
  byte	8-bit signed two's-complement integer
  short	16-bit signed two's-complement integer
  int	32-bit signed two's-complement integer
  long	64-bit signed two's-complement integer
  float	32-bit IEEE 754-1985 floating-point number
  double	64-bit IEEE 754-1985 floating-point number

• Literals for primitive types

• Programming with primitive types

• Passing primitive types as method arguments

Objects

• Example: class java.awt.Point

• A variable of a nonprimitive type holds a reference to an object
  • The null reference

• Assigning an object's reference (aliasing)

• Duplicating an object's contents (copying)

• Testing objects for identity (== and !=): are the references the same?

• Testing objects for equality (equals() and !equals()): are the contents the same?

• Passing nonprimitive types as method arguments

Strings

• Every string is an object, an instance of class java.lang.String

• String literals

• String operators: concatenation  +  +=

• String identity vs. string equality

Control Statements

• For loop

• For-each loop

• If-then-else

• Return statement (in a method)
  • Returning a boolean value

• While loop, do-while loop

Arrays and Matrices

• Array variable declaration, creation, initialization, indexing
  • An object array is an array of references to objects
  • array.length

• Matrix variable declaration, creation, initialization, indexing
  • A matrix is an array of references to arrays

Advanced Programming • 4003-707-02 • Fall Quarter 2008

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Alan Kaminsky • Department of Computer Science • Rochester Institute of Technology • 4486 + 2220 = 6706

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