map遍历的几种方法

importjava.util.ArrayList;importjava.util.HashMap;importjava.util.Iterator;importjava.util.List;importjava.util.Map;importjava.util.Set;一：  System.out.println("方法一");  Iterator it = tempMap.entrySet().iterator();  while(it.hasNext()) {   Map.Entry entry = (Map.Entry) it.next();   Object key = entry.getKey();   Object value = entry.getValue();   System.out.println("key="+ key + " value="+ value);  }二：  // JDK1.5中,应用新特性For-Each循环  for(Map.Entry<String, Integer> entry : tempMap.entrySet()) {   String key = entry.getKey().toString();   String value = entry.getValue().toString();   System.out.println("key="+ key + " value="+ value);  }三：  // 遍历方法三 hashmap keySet() 遍历  System.out.println("方法三");  for(Iterator i = tempMap.keySet().iterator(); i.hasNext();) {   Object obj = i.next();   System.out.println(obj);// 循环输出key   System.out.println("key="+ obj + " value="+ tempMap.get(obj));  }  for(Iterator i = tempMap.values().iterator(); i.hasNext();) {   Object obj = i.next();   System.out.println(obj);// 循环输出value  }四：  // 遍历方法四 treemap keySet()遍历  System.out.println("方法四");  for(Object o : tempMap.keySet()) {   System.out.println("key="+ o + " value="+ tempMap.get(o));  }遍历Map <String, ArrayList> map = new HashMap<String, ArrayList>();  Map<String, ArrayList> map = newHashMap<String, ArrayList>();  Set<String> keys = map.keySet();  Iterator<String> iterator = keys.iterator();  while(iterator.hasNext()) {   String key = iterator.next();   ArrayList arrayList = map.get(key);   for(Object o : arrayList) {    System.out.println(o + "遍历过程");   }  }  System.out.println("2222");  Map<String, List> mapList = newHashMap<String, List>();  for(Map.Entry entry : mapList.entrySet()) {   String key = entry.getKey().toString();   List<String> values = (List) entry.getValue();   for(String value : values) {    System.out.println(key + " --> "+ value);   }  }