java arrays by srinivas reddy.s . arrays collection of similar data types stages declaration...
TRANSCRIPT
Java Arrays
BySrinivas Reddy.S
www.java9s.com
Arrays
• Collection of similar data typesStages
• Declaration• Construction• Initialization
www.java9s.com
Declaration
• Declaring Arrays: int[] marks; byte[] age;
Less readable: int marks[]; byte age[];
www.java9s.com
Construction
int[] marks;marks = new int[5];“The size of the array is mandatory”In single line:int[] marks = new int[5];
marks
www.java9s.com
Initialization• Initialization is loading the array with the values.int[] marks = new int[5];
marks[0] =20;marks[1]=49;marks[2] =30;marks[3] = 67;marks[4] = 35;
0 1 2 43
20 49 30 67 35
www.java9s.com
Initialization – Objects
class Pen{ }Pen[] pens = new Pen[3];pens[0] = new Pen();Pens[1] = new Pen();Pens[2] = new Pen();
0 1 2
www.java9s.com
Array Initializer.
• int[] marks ={20,39,40,30};
Array Initializer
www.java9s.com
Two dimensional Array
• int[][] marks = new int[2][3];marks[0][0] = 30;marks[0][1]=31;marks[0][2]=32;marks[1][0]=40;marks[1][1]=41;marks[1][2]=42;
0 1
0 1 0 1 22
30 31 40 4132 42
www.java9s.com
Two dimension- non uniform
• int[][] marks = new int[2];• marks[0] = new int[3];• marks[1] = new int[4];
0 1
0 1 20 1 2 3
www.java9s.com
Multidimensional Arrays
• int[][][] marks = new int[2][3][2];0 1
0 1 2 0 1 2
0 1 0 1 0 1 0 1 0 1 0 1
www.JAVA9S.com