Comparable vs Comparator in Java

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Comparable vs Comparator in Java

Java provides two interfaces to sort objects using data members of the class:
  1) Comparable
  2) Comparator

Comparator
A comparator interface is used to order the objects of user-defined classes.
A comparator object is capable of comparing two objects of the same class.

public int compare(Object obj1, Object obj2):
class Sortbyname implements Comparator<Student> {
  // Method
  // Sorting in ascending order of name
  public int compare(Student a, Student b) {
    return a.name.compareTo(b.name);
  }
}

Comparable
A comparable object is capable of comparing itself with another object.

class Movie implements Comparable<Movie>{
  public int compareTo(Movie m) {
    return this.year - m.year;
  }
}

using comparator we were able to use different attributes.
using comparable we can use only one comparison.

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