利用java做排序

一、应用TreeMap做排序，代码以下：

java.util.SortedMap<Double, scala.Tuple2<String,String>> topN = new java.util.TreeMap<Double, scala.Tuple2<String,String>>();


	    topN.put(-0.223,new scala.Tuple2<String,String>("1","1"));
	    topN.put(-0.5239,new scala.Tuple2<String,String>("2","1"));
	    topN.put(-0.323,new scala.Tuple2<String,String>("3","1"));
	    topN.put(-0.423,new scala.Tuple2<String,String>("4","1"));
	    topN.put(-0.523,new scala.Tuple2<String,String>("5","1"));
	    topN.put(-0.623,new scala.Tuple2<String,String>("6","1"));
	     
	    for (Map.Entry<Double, scala.Tuple2<String,String>> entry : topN.entrySet()) {
	    	 System.out.println(entry.getValue()._1); 
	     }java.util.SortedMap<Double, s