Java Map 按Key排序
package test;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
public class Demo {
private HashMap<Integer, Object> map =new HashMap<Integer, Object>();
private Set<Integer> keySet = map.keySet();
public Object get(Integer key) {
return map.get(key);
}
public void put(Integer key, Object value) {
map.put(key, value);
}
@SuppressWarnings("unchecked")
public void sort() {
List<Integer> list =new ArrayList<Integer>(map.keySet());
Collections.sort(list, new Comparator<Object>(){
public int compare(Object a, Object b) {
return a.toString().toLowerCase().compareTo(b.toString().toLowerCase());
}
});
this.keySet = new TreeSet<Integer>(list);
}
public Set<Integer> keySet() {
return this.key
}
public static void main(String [] args){
Demo map= new Demo();
map.put(11, "加");
map.put(12, "关");
map.put(13, "注");
map.put(10, "添");
map.put(1, "小");
map.put(8, "记");
map.put(9, "得");
map.put(7, "客");
map.put(5, "的");
map.put(6, "博");
map.put(4, "豆");
map.put(3, "糖");
map.put(2, "小");
System.out.println("排序前");
for (Iterator it =map.keySet().iterator();();){
Integer key= (Integer)it.next();
System.out.println( "key[ " + key + "], value[ " + map.get(key) + "] ");
}
//
System.out.println("排序后");
System.out.println( "\n ");
map.sort();
for (Iterator it=map.keySet().iterator();();) {
Integer key=(Integer)it.next();
System.out.println( "key[ " + key + "], value[ " + map.get(key) + "] ");
}
}
}