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Java Tutorial : Java Static Initialization block

StaticInitializationTest.java

public class StaticInitializationTest
{
    public static int capacity;

    private static boolean flag;

    static
    {
        System.out.println("Static initialization block is called. ");
        // initialize to 10
        capacity = 10;

        // initialize to false
        flag = true;
    }

    public static void main(String args[])
    {
        System.out.println("capacity : " + capacity);
        System.out.println("flag     : " + flag);
    }
}