Print the elemenets of HashMap, Hashtable or any Map in Java

1. Iterating or looping map using foreach loop.

for (String key : profiles.keySet()) {

     System.out.println("key:"+key+"value:"+profiles.get(key));

}

2. Looping HashMap in Java using EntrySet and for loop.

for (Entry<String, String> entry : entrySet) {

     System.out.println("key:"+entry.getKey()+"value:"+entry.getValue());

}

3. Iterating Map in Java using KeySet Iterator.

Set<String> keySet = profiles.keySet();

Iterator<String> keySetIterator = keySet.iterator();

while (keySetIterator.hasNext()) {

      String key = keySetIterator.next();

      System.out.println("key:"+key+"value:"+profiles.get(key));

}

4. Iterating HashMap in Java using EntrySet and Java iterator.

Set<Entry<String,String>> entrySet1 = profiles.entrySet();

Iterator<Entry<String, String>>  iter  = entrySet1.iterator();

while(iter.hasNext()) {

      Entry<String, String>  entry = iter.next();

      System.out.println("key:"+entry.getKey()+

                          "value:"+entry.getValue());

}

HashMapIterator.java

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Set;

public class HashMapIterator {

    public static void main(String[] args) {

          Map<String, String> profiles = new HashMap<String, String>();

          profiles.put("sattu", "developer");

          profiles.put("sameer", "senior developer");

          profiles.put("shan", "architect");

          System.out.println("Iterating or looping map using Java5 foreach loop");

          for (String key : profiles.keySet()) {

                System.out.println("key:"+key+

                              "value:"+profiles.get(key));

          }

          System.out.println("Looping HashMap in Java using EntrySet");

          Set<Map.Entry<String, String>> entrySet = profiles.entrySet();

          for (Entry<String, String> entry : entrySet) {

               System.out.println("key:"+entry.getKey()+

                              "value:"+entry.getValue());

          }

          System.out.println("Looping HashMap in Java using EntrySet iterator");

          Set<Entry<String,String>> entrySet1 = profiles.entrySet();

          Iterator<Entry<String, String>>  iter  = entrySet1.iterator();

          while(iter.hasNext()) {

                 Entry<String, String>  entry = iter.next();

                 System.out.println("key:"+entry.getKey()+

                              "value:"+entry.getValue());

          }

          System.out.println("Iterating Map in Java using KeySet Iterator");

          Set<String> keySet = profiles.keySet();

          Iterator<String> keySetIterator = keySet.iterator();

          while (keySetIterator.hasNext()) {

                 String key = keySetIterator.next();

                 System.out.println("key:"+key+

                            "value:"+profiles.get(key));

          }

   }

}