java - map 的大小限制为 3 个元素

Question

我正在尝试用 Java 填充 map ，但由于某种原因，它不允许 map 拥有超过 3 个元素，即使我想要更多。我该如何解决这个问题？

这是java代码，它恰好位于spring mvc应用程序的 Controller 方法中:

@ModelAttribute("addLinkOptions") 
public Map loadLinkOptions(){ 
    LinkedHashMap<String, String> addLinks = new LinkedHashMap<String,String>(); 
    addLinks.put("/calendar?day=2014-01-10","New this"); 
    System.out.println(" ......1 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New that"); 
    System.out.println(" ......2 size of addlinks is: "+addLinks.size());
    addLinks.put("/otherlink","New some other thing"); 
    System.out.println(" ......3 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New dog"); 
    System.out.println(" ......4 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New cat"); 
    System.out.println(" ......5 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New Car"); 
    System.out.println(" ......6 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New lizard"); 
    System.out.println(" ......7 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New bike"); 
    System.out.println(" ......8 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New motorcycle"); 
    System.out.println(" ......9 size of addlinks is: "+addLinks.size());
    addLinks.put("/","New frog"); 
    System.out.println(" ......10 size of addlinks is: "+addLinks.size());
    return addLinks;
}  

 ......1 size of addlinks is: 1
 ......2 size of addlinks is: 2
 ......3 size of addlinks is: 3
 ......4 size of addlinks is: 3
 ......5 size of addlinks is: 3
 ......6 size of addlinks is: 3
 ......7 size of addlinks is: 3
 ......8 size of addlinks is: 3
 ......9 size of addlinks is: 3
 ......10 size of addlinks is: 3
 ......10 size of addlinks is: 3

Answer 1

map 是一个键/值存储，每个键都是唯一的，使用相同键添加值将覆盖该键之前的值。