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Java Quiz: Nested Classes

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Java Quiz: Nested Classes

What happens when you try to compile and run the following program?

· Java Zone
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Starting today, every week, we'll be bringing you a new quiz/puzzler/brain-teaser to help keep you on top of your Java game. Here's your first question: 

What Happens When You Try to Compile and Run the Following Program?

class Outer {

    private int a = 12;
    private int b = 6;

    Outer() {

        NestedA nestedA = new NestedA(4);
        a = a -12;
    class NestedA {

        NestedA(int y){

            NestedB nestedB = new NestedB(y);
            nestedB.methodB(y, a);
            a= a + b - y;
        private void methodA(int z) {

        class NestedB {

            NestedB(int i) {
                a = a - i; b = b +i;
            private void methodB(int x, int z) {
                if(x < 5) {
                    a = a+x+b;
                b = b+z; 
    public static void main(String[] args) {

        NestedA nestedA = new Outer().new NestedA(2);

Submit your answer here (no compiling!):

Was this too difficult? Too easy? What other topics would you like to see Sar test you on? Let us know your thoughts in the comments!

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