java - Multiple Field Collection Sort -

i have class arraylist contains value string word, string expandedword, double confidence, double support

i want sort arraylist based on confidence, , based on support.

i have succeed sort arraylist based on confidence, failed make new method sort arraylist based on support

this code sort based on confidence

public class expandedterm implements comparable<expandedterm> { string word; string expandedword; double support; double confidence;  public expandedterm (string word,string expandedword, double confidence,double support){     this.word = word;     this.expandedword = expandedword;     this.support = support;     this.confidence = confidence; }  public string getword(){     return word; }  public string expandedword(){     return expandedword; }  public double getsupport(){     return support; }  public double getconfidence(){     return confidence; }  @override public int compareto(expandedterm conf) {     return new double(this.confidence).compareto(new double(conf.confidence)); } 

i failed make method compareto, sort based on support value. how sort first confidence, , make method sort support value?

user comparator this. compaarble provide functionality sort on single type basis. here link found when use comparable , comapartor
http://iandjava.blogspot.in/2012/10/comparable-and-comparator.html

use multiple comparartor

• one confidence

     public class confidancecomparator implements comparator<expandedterm> {         @override         public int compare(final expandedterm  o1, final expandedterm  o2) {             return new double(o1.confidence).compareto(new double(o2.confidence));         }     } 

• one support

     public class supportcomparator implements comparator<expandedterm> {         @override         public int compare(final expandedterm  o1, final expandedterm  o2) {             return new double(o1.support).compareto(new double(o2.support));         }     } 

and use collections.sort(<list>, <comparator>) adn desired list.

this required when want sort either on confidance basis or support basis.
if required first sort on confidance basis , if confidance equal check support basis. comparable sufficient , is

public int compareto(expandedterm conf) {     int compare = new double(this.confidence).compareto(new double(conf.confidence));      if (compare == 0) {         compare = new double(this.support).compareto(new double(conf.support));     }     return compare; }