class
Static array shared between class instances
This is an example of how to create a static
array shared between class instances. The example is described in short below:
- We have created a class,
SharedArray
, that has astatic
int array, initialized with length 10. - In a static block, the array is initialized with random int values, using
random()
API method of Math. - The class also has a
printArray()
method, that prints the values of the array. - We create a new instance of
SharedArray
that isa1
and useprintArray()
method to print the values of the static array. - Then we create a new instance of
SharedArray
, that isa2
and print out the static array values again. - Then we use
printArray()
method of a1 object. - The static array in
a1
instance has the same values that it had whena2
was initialized.
Let’s take a look at the code snippet that follows:
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 | package com.javacodegeeks.snippets.core; public class SharedArray { static int [] array = new int [ 10 ]; { System.out.println(); System.out.println( "Running initialization block." ); for ( int i = 0 ; i < array.length; i++) { array[i] = ( int ) ( 100.0 * Math.random()); } } void printArray() { for ( int i = 0 ; i < array.length; i++) { System.out.print( " " + array[i]); } } public static void main(String[] args) { SharedArray a1 = new SharedArray(); a1.printArray(); SharedArray a2 = new SharedArray(); a2.printArray(); System.out.println(); a1.printArray(); System.out.println(); } } |
Output:
Running initialization block.
33 33 35 56 75 66 73 68 69 35
Running initialization block.
63 2 0 76 78 34 35 80 91 92
63 2 0 76 78 34 35 80 91 92
This was an example of how to create a static array shared between class instances in Java.