diff --git a/javaSE-day04/src/com/inmind/map01/MapDemo03.java b/javaSE-day04/src/com/inmind/map01/MapDemo03.java new file mode 100644 index 0000000..d46588c --- /dev/null +++ b/javaSE-day04/src/com/inmind/map01/MapDemo03.java @@ -0,0 +1,41 @@ +package com.inmind.map01; + +import java.util.HashMap; +import java.util.Iterator; +import java.util.Map; +import java.util.Map.Entry; +import java.util.Set; + +/* + 键值对遍历 + - public Set> entrySet(): 获取到Map集合中所有的键值对对象的集合(Set集合)。 + */ +public class MapDemo03 { + public static void main(String[] args) { + //创建一个双列集合,K为String,V也为String + Map map = new HashMap<>(); + //添加一对数据(增加) + map.put("刘备", "孙尚香"); + map.put("吕布", "貂蝉"); + map.put("董卓", "貂蝉"); + System.out.println(map); + + //直接获取双列集合所有的键值对对象 + Set> entries = map.entrySet(); + + //迭代器遍历键值对 + Iterator> iterator = entries.iterator(); + while (iterator.hasNext()) { + Entry entry = iterator.next(); + System.out.println(entry.getKey()+"-"+entry.getValue()); + } + System.out.println("-------------------------------------"); + //foreach遍历键值对 + for (Entry entry : entries) { + System.out.println(entry.getKey()+"-"+entry.getValue()); + } + + + + } +}