相关疑难解决方法(0)

我正在尝试找出可以检索HashMap中的值的顺序.下面是代码片段.

import java.util.HashMap;

public class HashMapExample {

   public static void main(String[] args) {
       HashMap<Integer, String> hashmap = new HashMap<Integer, String>();
       hashmap.put(1, "apple" );
       hashmap.put(2, "lemon" );
       hashmap.put(3, "orange" );
       hashmap.put(4, "banana" );
       hashmap.put(5, "litchi" );
       hashmap.put(6, "mango" );
       hashmap.put(7, "papaya" );

       System.out.println(hashmap.size());

       for (String key : hashmap.values()) {
           System.out.println(key);
       }
   }
}

输出:

7
apple
lemon
orange
banana
litchi
mango
papaya

值按插入顺序打印.一般来说这是真的吗？我期待值以任意顺序打印.这是使用Java 6.

我在地图中保存产品的详细信息,并添加ArrayList <HashMap <String,String >>并设置为自定义列表适配器.我需要按价格对价值进行排序.怎么实现呢？提前致谢.

我正进入（状态

  List<Map<String,Object>> listMap = [
    {employee=17, fromdate=2010-08-01 00:00:00.0, full_inc=25572.0000},
    {employee=17, fromdate=2010-09-01 00:00:00.0, full_inc=28347.0000},  
    {employee=17, fromdate=2010-10-01 00:00:00.0, full_inc=37471.0000},
    {employee=17, fromdate=2011-02-01 00:00:00.0, full_inc=47033.0000},
    {employee=17, fromdate=2011-07-01 00:00:00.0, full_inc=50592.0000}
  ]

谁能帮我如何在java中根据full_inc从高到低对这个地图列表进行排序