Java Map集合遍历

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package testMap;import java.util.ArrayList;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Map.Entry;import java.util.Set;/** * 循环遍历Map集合 *  * @author Administrator *  */public class CircleMap {    public static void main(String[] args) {        Map<Integer, String> tempMap = new HashMap<Integer, String>();        tempMap.put(1, "张三");        tempMap.put(2, "李四");        tempMap.put(3, "王五");        /**         * JDK1.4中 遍历方法一 hashmap entrySet() 遍历         */        System.out.println("------------------------------------------------------");        System.out.println("");        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);        }        /**         * JDK1.5中,应用新特性For-Each循环         */        System.out.println("");        System.out.println("方法二：");        for (Map.Entry<Integer, String> entry : tempMap.entrySet()) {            String key = entry.getKey().toString();            String value = entry.getValue().toString();            System.out.println("key = " + key + " value = " + value);        }        /**         * 遍历方法三 hashmap keySet() 遍历         */        System.out.println("");        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        }        /**         * 遍历方法四 treemap keySet()遍历         */        System.out.println("");        System.out.println("方法四");        for (Object o : tempMap.keySet()) {            System.out.println("key = " + o + " value = " + tempMap.get(o));        }        System.out                .println("------------------------------------------------------");    }}
这里写图片描述
自己都测试过了的。喜欢的就给顶一下！
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