Java笔记总结（四十八）---map的遍历

package MapTest;

import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;

public class mapTest {
    public static void main(String[] args) {
        HashMap hashMap = new HashMap();
        hashMap.put("张三", 12);
        hashMap.put("李四", 27);
        hashMap.put("王五", 15);

//        System.out.println(hashMap);

        Set set = hashMap.keySet();
        for (Object o : set) {
            System.out.println(o + "-" + hashMap.get(o));
        }

        System.out.println("=============");
        Iterator iterator = set.iterator();
        while (iterator.hasNext()) {
            Object next = iterator.next();
            System.out.println(next + "-" + hashMap.get(next));
        }

       //只获取values
        Collection values = hashMap.values();
        for (Object o : values) {
            System.out.println(o);
        }

        System.out.println("=============");

        Iterator iterator1 = values.iterator();
        while (iterator1.hasNext()) {
            Object next1 =  iterator1.next();
            System.out.println(next1);

        }
    }
}

输出结果：
李四-27
张三-12
王五-15

=============
李四-27
张三-12
王五-15

=============
27
12
15

=============
27
12
15