diff --git a/javaSE-day04/src/com/inmind/map01/LinkedHashMapDemo05.java b/javaSE-day04/src/com/inmind/map01/LinkedHashMapDemo05.java new file mode 100644 index 0000000..0ff9358 --- /dev/null +++ b/javaSE-day04/src/com/inmind/map01/LinkedHashMapDemo05.java @@ -0,0 +1,49 @@ +package com.inmind.map01; + +import java.util.HashMap; +import java.util.LinkedHashMap; +import java.util.Map; +import java.util.Set; + +/* +HashMap的特点: +1.存取无序 +2.没有索引 +3.不能重复 + +LinkedHashMap的特点 + hash:哈希表,它的作用是去重 + Link:链表,它的作用保存顺序 + + LinkedHashMap:存储有序,没有索引,不能重复,跟LinkedHashSet是类似的 + */ +public class LinkedHashMapDemo05 { + public static void main(String[] args) { + + HashMap map = new HashMap<>(); + + map.put(new Student("张三", 18), "苏州"); + map.put(new Student("李四", 19), "无锡"); + map.put(new Student("王五", 20), "常州"); + + //键找值的方法遍历 + Set keys = map.keySet(); + for (Student key : keys) { + System.out.println(key+"-"+map.get(key)); + } + System.out.println("-------------------------"); + + LinkedHashMap linkedmap = new LinkedHashMap<>(); + + linkedmap.put(new Student("张三", 18), "苏州"); + linkedmap.put(new Student("李四", 19), "无锡"); + linkedmap.put(new Student("王五", 20), "常州"); + + //键值对遍历 + Set> entries = linkedmap.entrySet(); + for (Map.Entry entry : entries) { + System.out.println(entry.getKey()+":"+entry.getValue()); + } + + } +}