sorting class array java

Question

I have made a class as follows:

class strVal{
    double val;
    String str;
}

Now I made an array of this class now I want to sort that array by strVal.val. I want to know if there is any standard defined method in Java?

Answer 1

Implement java.lang.Comparable interface, and use java.util.Arrays.sort(...) to sort an array of StrVal:

public class StrVal implements Comparable<StrVal> {

  private double val;
  private String str;

  public StrVal(double val, String str) {
    this.val = val;
    this.str = str;
  }

  @Override
  public int compareTo(StrVal o) {
    return (int)(this.val - o.val);
  }

  public double getVal() {
    return val;
  }

  public String getStr() {
    return str;
  }
}

To sort the array :

StrVal[] array;

...

Arrays.sort(array)