packagecom.cn.util;importjava.util.ArrayList;importjava.util.HashMap;importjava.util.Iterator;importjava.util.List;importjava.util.Map;importjava.util.Set;//循环遍历map的方法
public classUtil {public static voidmain(String[] args) {
Map tempMap = new HashMap();
tempMap.put("a", 1);
tempMap.put("b", 2);
tempMap.put("c", 3);//JDK1.4中//遍历方法一 hashmap entrySet() 遍历
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);
}
System.out.println("");//JDK1.5中,应用新特性For-Each循环//遍历方法二
System.out.println("方法二");for (Map.Entryentry : tempMap.entrySet()) {
String key=entry.getKey().toString();
String value=entry.getValue().toString();
System.out.println("key=" + key + " value=" +value);
}
System.out.println("");//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
}
System.out.println("");//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));
}
System.out.println("11111");//java如何遍历Map map = new HashMap ();
System.out
.println("java 遍历Map map = new HashMap ();");
Map map = new HashMap();
Set keys =map.keySet();
Iterator 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 mapList = new HashMap();for(Map.Entry entry : mapList.entrySet()) {
String key=entry.getKey().toString();
List values =(List) entry.getValue();for(String value : values) {
System.out.println(key+ " --> " +value);
}
}
}
}
