Question

I have code like this I need to access the mysample variable of static class InnerClass in the getInnerS() method which is inside the the NestedClass. I tried accessing it by creating a new object for InnerClass but i am getting java.lang.StackOverflowError.

public class NestedClass{
    private String outer = "Outer Class"; //NestedClass instance variable
    NestedClass.InnerClass innerClass = new NestedClass.InnerClass();

    void getOuterS(){
        System.out.println(outer); 
    }
    void getInnerS(){
        System.out.println(innerClass.mysample);
    }
    static class InnerClass{
        private String mysample = "Inner Class"; //InnerClass instance variable,
        NestedClass a = new NestedClass();
        void getIn(){
            System.out.println(mysample);
        }
        void getOut(){
            System.out.println(a.outer);
        }
    }
    public static void main(String[] args){
         NestedClass nestedClass = new NestedClass();
         NestedClass.InnerClass nestedInner = new NestedClass.InnerClass(); 
         nestedClass.getOuterS();
         nestedClass.getInnerS();
         nestedInner.getIn();
         nestedInner.getOut();
    }
}

Answer 1

NestedClass a = new NestedClass();

in static InnerClass class creates an instance of the NestedClass and as InnerClass is static this is a loop.

InnerClass does not need to be static, this should work

public class NestedClass {
private String outer = "Outer Class"; //NestedClass instance variable
NestedClass.InnerClass innerClass = new NestedClass.InnerClass();

void getOuterS(){
    System.out.println(outer); 
}
void getInnerS(){
    System.out.println(innerClass.mysample);
}
class InnerClass{
    private String mysample = "Inner Class"; //InnerClass instance variable,
    NestedClass a = NestedClass.this;
    void getIn(){
        System.out.println(mysample);
    }
    void getOut(){
        System.out.println(a.outer);
    }
}
public static void main(String[] args){
     NestedClass nestedClass = new NestedClass();
     NestedClass.InnerClass nestedInner = nestedClass.innerClass; 
     nestedClass.getOuterS();
     nestedClass.getInnerS();
     nestedInner.getIn();
     nestedInner.getOut();
}


}