按照HashMap中value值进行排序

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.LinkedHashMap;

/**
 * 测试HashMap按照value值排序输出
 * 先新建一个实现Comparable接口的类，将HashMap的元素用新建类封装，然后构建ArrayList，用Collection.sort排序
 * 
 * @author ywf
 * 
 */
public class Test {

	public static void main(String[] args) throws Exception {

		HashMap<String, Integer> input = new LinkedHashMap();// 需要用LinkedHashMap，保证输入的顺序和输出的顺序一致
		input.put("ywf", 65);
		input.put("lqq", 98);
		input.put("lp", 75);
		input.put("lj", 90);
		sort(input);
	}

	public static void sort(HashMap<String, Integer> input) {
		ArrayList<Pair> list = new ArrayList();
		for (String id : input.keySet()) {
			Pair pair = new Pair(id, input.get(id));
			list.add(pair);
		}
		Collections.sort(list);
		input.clear();
		for (Pair p : list) {
			input.put(p.id, p.value);
		}
		System.out.println(input);
	}

	@SuppressWarnings("rawtypes")
	static class Pair implements Comparable {
		String id;

		int value;

		public Pair(String id, int n) {
			this.id = id;
			this.value = n;
		}
		@Override
		public int compareTo(Object o) {
			// TODO Auto-generated method stub
			return this.value - ((Pair) o).value;
		}

	}
}