Java Traversal Object

in JDK1.4

Map map = new HashMap ();

    Iterator it = Map.entryset (). iterator ();

    while (It.hasnext ()) {

        Map.entry Entry = (map.entry) it.next ();

        Object key = Entry.getkey ();

        Object value = Entry.getvalue ();

}

JDK1.5, the application of new characteristics For-each cycle

Map m = new HashMap ();

For (Object O:map.keyset ()) {

    map.get (o);

}

Each element in the returned set is a map.entry type.

Private hashtable<string, string> emails = new hashtable<string, string> ();

In addition, we can change the HashMap to a set collection, then iterate the output, but the resulting object

Method One: Use EntrySet ()

   Iterator it = Emails.entryset (). iterator ();

   while (It.hasnext ()) {

    map.entry m= (map.entry) It.next ();

    Logger.info ("email-" + m.getkey () + ":" + m.getvalue ());

   }

  

   Method Two: jdk1.5 support, with EntrySet () and For-each Loop () for

   (map.entry<string, string> m:emails.entryset ()) {

   

    Logger.info ("email-" + m.getkey () + ":" + m.getvalue ());

   }

  

   Method Three: Use Keyset ()

   Iterator it = Emails.keyset (). iterator ();

   while (It.hasnext ()) {

    String key;

    key= (String) It.next ();

    Logger.info ("email-" + key + ":" + emails.get (key));

   }

Method Five: jdk1.5 support, with keyset () and For-each loops for

(Object m:emails.keyset ()) {

    logger.info ("email-" + m+ ":" + Emails.get (m));

   

Map AA = new HashMap ();

Aa.put ("Tmp1", New Object ());

Append substitution with the same function.

Aa.remove ("Temp1");

Delete

for (Iterator i = aa.values (). iterator ();    I.hasnext (); )    {

Object temp = I.next ();

}//Traversal

To a complete, treeset element that contains the interior sort.

public static void Main (string[] args) {arraylist<string> list = new arraylist<string> ();

   hashmap<object,object> hash = new hashmap<object,object> ();

   treemap<object,object> TreeMap = new treemap<object,object> ();

   List.add ("a");

   List.add ("B");

  

   List.add ("C");

   Hash.put (3, 3);

   Hash.put (4, 4);

   Hash.put (5, 5);

   Hash.put (6, 6);

   Hash.put (1, 1);

  

   Hash.put (2, 2);

   Treemap.put (1, 1);

   Treemap.put (2, 2);

   Treemap.put (3, 3);

   Treemap.put (4, 4);

   Treemap.put (5, 5);

  

   Treemap.put (6, 6);

   List traversal for (String m:list) {System.out.println (M); }//HashMap EntrySet () Traversal for (map.entry<object,object> M:hash.entryset ()) {System.out.println (M.getke

   Y () + "---" +m.getvalue ());

   //hashmap keyset () Traversal for (Object M:hash.keyset ()) {System.out.println (m+ "---" +hash.get (m)); }//TreeMap keyset () Traversal for (Object M:treemap.keyset ()) {SYSTEM.OUt.println (m+ "---" +treemap.get (m)); }

}