Java MAP三种遍历方法

package sean;import java.util.*;public class MapTraverse {public static void main(String[] args) {String[] str = {"I love you", "You love he", "He love her", "She love me"};Map<Integer, String> m = new HashMap<Integer, String>();for(int i=0; i<str.length; i++) {m.put(i, str[i]);}System.out.println("结果1---：");PrintMethod1(m);System.out.println("结果2---：");PrintMethod2(m);System.out.println("结果3---：");PrintMethod3(m);}public static void PrintMethod1(Map<Integer, String> m) {for (Integer Key : m.keySet()){System.out.println(Key + ":\t" + m.get(Key));}// 原理参考/*Set s = (Set<Integer>)m.keySet();Iterator<Integer> it = s.iterator();int Key;String value;while(it.hasNext()) {Key = it.next();value = (String)m.get(Key);System.out.println(Key+":\t"+value);}*/}public static void PrintMethod2(Map<Integer, String> m) {for (Map.Entry<Integer, String> entry : m.entrySet()){System.out.println(entry.getKey() + ":\t" + entry.getValue());}// 原理参考/*Iterator<Map.Entry<Integer, String>> it = m.entrySet().iterator();Map.Entry<Integer, String> entry;int Key;String value;while(it.hasNext()) {entry = it.next();Key = entry.getKey();value = entry.getValue();System.out.println(Key+":\t"+value);}*/}public static void PrintMethod3(Map<Integer, String> m) {for (String value : m.values()){System.out.println(value);}// 原理参考/*int Key;String value;for(Map.Entry<Integer, String> entry : m.entrySet()) {Key = entry.getKey();value = entry.getValue();System.out.println(Key+":\t"+value);}*/}}

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