update linkedHashmap

3 Hash Table/LinkedHashMap.md

@@ -6,6 +6,24 @@ HashMap是无序的，迭代访问顺序并不一定与插入(put)顺序一致
 
 
 ```
+//插入有序
+        Map<String, String> linkedHashMap = new LinkedHashMap<>();
+        linkedHashMap.put("name1", "josan1");
+        linkedHashMap.put("name2", "josan2");
+        linkedHashMap.put("name3", "josan3");
+        Set<Entry<String, String>> set = linkedHashMap.entrySet();
+        Iterator<Entry<String, String>> iterator = set.iterator();
+        while(iterator.hasNext()) {
+            Entry entry = iterator.next();
+            String key = (String) entry.getKey();
+            String value = (String) entry.getValue();
+            System.out.println("key:" + key + ",value:" + value);
+        }
+
+output:
+key:name1, value:josan1        
+key:name2, value:josan2        
+key:name3, value:josan3        
 ```