Making Your Objects Comparable and Sortable : Collections Framework « Collections « Java Tutorial






  1. Java Tutorial
  2. Collections
  3. Collections Framework

You can make objects comparable by implementing the java.lang.Comparable and java.util.Comparator interfaces.

Classes such as java.lang.String, java.util.Date, and primitive wrapper classes all implement java.lang.Comparable.

import java.util.Arrays;

public class MainClass {

  public static void main(String[] args) {
    int[] intArray = new int[] { 5, 4, 3, 2, 1 };
    Arrays.sort(intArray);
    for (int i : intArray) {
      System.out.println(i);

    }
  }

}

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9.1.Collections Framework
9.1.1.The Collections Framework consists of three parts
9.1.2.Framework Interfaces
9.1.3.Interface type and its implementation
9.1.4.Conversion of different Collection data types
9.1.5.Making Your Objects Comparable and Sortable
9.1.6.Using Comparable and Comparator
9.1.7.Deep clone collection: Returns a new collection containing clones of all the items in the specified collection.