MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import java.util.HashMap;
import java.util.Map;

public class MainClass {
    public static void main(String[] a) {

        Map map = new HashMap();
        map.put("key1", "value1");
        map.put("key2", "value2");
        map.put("key3", "value3");
        map.put(null, null);

        System.out.println(map);
    }
}