Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class Main {
    public static final void main(String[] ignored) {
        Map<Integer, List<String>> mapOfIntStrs = new HashMap<Integer, List<String>>();

        add(mapOfIntStrs, 1, "one");
        add(mapOfIntStrs, 1, "two");
        add(mapOfIntStrs, 1, "three");
        add(mapOfIntStrs, 2, "four");
        add(mapOfIntStrs, 2, "five");
        add(mapOfIntStrs, 3, "six");
        add(mapOfIntStrs, 3, "seven");

        Set<Integer> keySet = mapOfIntStrs.keySet();

        for (int i : keySet) {
            List<String> strList = mapOfIntStrs.get(i);
            System.out.println(i);
            for (String s : strList) {
                System.out.println("  " + s);
            }
        }
    }

    private static final void add(Map<Integer, List<String>> mapTo_addTo, int keyNum, String value) {
        if (mapTo_addTo.containsKey(keyNum)) {
            mapTo_addTo.get(keyNum).add(value);
        } else {
            List<String> strList = new ArrayList<String>();
            strList.add(value);
            mapTo_addTo.put(keyNum, strList);
        }
    }
}