Loop map

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package com.mkyong;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

public class LoopMap {

public static void main(String[] args) {    // initial a Map    Map<String, String> map = new HashMap<String, String>();    map.put("1", "Jan");    map.put("2", "Feb");    map.put("3", "Mar");    map.put("4", "Apr");    map.put("5", "May");    map.put("6", "Jun");    // Map -> Set -> Iterator -> Map.Entry -> troublesome, not recommend!    System.out.println("\nExample 1...");    Iterator<Entry<String,String>> iterator = map.entrySet().iterator();    while (iterator.hasNext()) {        Map.Entry<String,String> entry = (Map.Entry<String,String>) iterator.next();        System.out.println("Key : " + entry.getKey() + " Value :" + entry.getValue());    }    // more elegant way, this should be the standard way, recommend!    System.out.println("\nExample 2...");    for (Map.Entry<String, String> entry : map.entrySet()) {        System.out.println("Key : " + entry.getKey() + " Value : " + entry.getValue());    }    // weired, but works anyway, not recommend!    System.out.println("\nExample 3...");    for (Object key : map.keySet()) {        System.out.println("Key : " + key.toString() + " Value : " + map.get(key));    }    //Java 8 only, forEach and Lambda. recommend!    System.out.println("\nExample 4...");    map.forEach((k,v)->System.out.println("Key : " + k + " Value : " + v));}

}

Example 1…
Key : 1 Value :Jan
Key : 2 Value :Feb
Key : 3 Value :Mar
Key : 4 Value :Apr
Key : 5 Value :May
Key : 6 Value :Jun

Example 2…
Key : 1 Value : Jan
Key : 2 Value : Feb
Key : 3 Value : Mar
Key : 4 Value : Apr
Key : 5 Value : May
Key : 6 Value : Jun

Example 3…
Key : 1 Value : Jan
Key : 2 Value : Feb
Key : 3 Value : Mar
Key : 4 Value : Apr
Key : 5 Value : May
Key : 6 Value : Jun

Example 4…
Key : 1 Value : Jan
Key : 2 Value : Feb
Key : 3 Value : Mar
Key : 4 Value : Apr
Key : 5 Value : May
Key : 6 Value : Jun

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