- Import Java.util.HashMap;
- Import Java.util.Iterator;
- Import Java.util.Map;
- Import Java.util.Set;
- Import Java.util.Map.Entry;
- /**
- * The map set is as unordered as the set set
- * Several common methods for map collection traversal
- * @author Owner
- *
- */
- Public class MapTest5 {
- public static void Main (string[] args) {
- map<string, string> map = new hashmap<string, string> ();
- Map.put ("A", "Zhangsan");
- Map.put ("B", "Lisi");
- Map.put ("C", "Wangwu");
- SYSTEM.OUT.PRINTLN (map);
- /**
- * Method One traversal map
- */
- set<string> KeySet = Map.keyset ();
- For (iterator<string> Iterator = Keyset.iterator (); Iterator.hasnext ();) {
- String key = Iterator.next ();
- String value = Map.get (key);
- System.out.println (key+"=" +value);
- }
- System.out.println ("**********************");
- /**
- * Method Two Calendar map
- */
- For (String Key:map.keySet ()) {
- System.out.println (key+"=" +map.get (key));
- }
- System.out.println ("**********************");
- /**
- * Method Three traversal map, it is recommended to use this method to traverse the map collection, especially when the capacity is large
- */
- for (map.entry<string, string> entry:map.entrySet ()) {
- System.out.println (Entry.getkey () +"=" +entry.getvalue ());
- }
- System.out.println ("**********************");
- /**
- * Method Four Calendar Map
- */
- set<entry<string, string>> entryset = Map.entryset ();
- for (iterator<map.entry<string, string>> Iterator = Entryset.iterator (); Iterator.hasnext ();) {
- map.entry<string, string> Entry = Iterator.next ();
- System.out.println (Entry.getkey () +"=" +entry.getvalue ());
- }
- System.out.println ("**********************");
- /**
- * Method Five, this method iterates over all the values
- */
- For (String value:map.values ()) {
- System.out.println (value);
- }
- }
- }
Several common methods of map collection traversal