Jtable column sorting

Question

Hi all,
I have jtable wirh setAutoCreateRowSorter(true); . The columns with Double object are sorting correctly. One column values are object of our class "Carat". But this column is not sorting like numbers. What are the changes I have to do to sort like number or Double.?
my custom class Carat is
import java.io.Serializable;
import common.Common;
public class Carat implements Serializable{
     private static final long serialVersionUID = 7876408747596231364L;
     Double carat;
     public Carat(double carat){
          this.carat = new Double(carat);
     public double doubleValue(){
          return carat.doubleValue();
     public void setCarat(Double carat){
          this.carat = carat;
     //here round to 3 decimal
     public String toString(){
          return Common.roundCarat(carat.doubleValue());
     public Double getDoubleValue(){
          return carat;
     public Carat getDifference(Carat cat){
          return new Carat(this.carat.doubleValue() - cat.doubleValue());
     public boolean equals(Carat cart){
          if(this.carat.doubleValue() == cart.doubleValue()){
               return true;
          return true;
     public int compareTo(Carat anotherDouble) {
        return Double.compare(carat.doubleValue(), anotherDouble.doubleValue());
}Ant suggestions ...plz help....

Answer 1

You have to implement the Compareable-Interface.
Also the compareTo-Implementation is wrong:
use Object for the parameter type.
public class Carat implements Serializable, Compareable {
public int compareTo( Object that ){
}Read the book Java "Effective Java" :)
IMHO this post is not in the correct thread...