.How to instantiate the innerclass from another class with coded eg.

Question

How to instantiate the innerclass from another class(both for static & non static) please give me an eg with coding.

Answer 1

It's just a preference, but I like writing factory methods:
public class Outer {
    public class Inner {}
    public static class StaticInner {}
    public Inner innerInstance() {
        return new Inner();
    public static StaticInner staticInnerInstance() {
        return new StaticInner();
    public static void main(String[] args) {
        Outer.StaticInner si = Outer.staticInnerInstance();
        Outer outer = new Outer();
        Outer.Inner i = outer.innerInstance();
}Often, for me, the inner class implements an interface, and the factory method
lets you hide the implementation class:
public class Outer {
    private class Inner implements Runnable {
        public void run() {}
    public Runnable runnerInstance() {
        return new Inner();
    public static void main(String[] args) {
        Outer outer = new Outer();
        Runnable r = outer.runnerInstance();
}