SortedSet containsAll() method in Java with Examples (original) (raw)

Last Updated : 30 Sep, 2019

The containsAll() method of Java SortedSet is used to check whether two sets contain the same elements or not. It takes one set as a parameter and returns True if all of the elements of this set is present in the other set.Syntax:

public boolean containsAll(Collection C)

Parameters: The parameter C is a Collection. This parameter refers to the set whose elements occurrence is needed to be checked in this set.Return Value: The method returns True if this set contains all the elements of other set otherwise it returns False.Note: The containsAll() method in SortedSet is inherited from the Set interface in Java. Below programs illustrate the Set.containsAll() method:Program 1:

Java `

// Java code to illustrate // Set containsAll()

import java.util.*;

class SortedSetDemo { public static void main(String args[]) {

    // Creating an empty set
    SortedSet<String>
        set = new TreeSet<String>();

    // Use add() method to
    // add elements in the set
    set.add("Geeks");
    set.add("for");
    set.add("Geeks");
    set.add("10");
    set.add("20");

    // prints the set
    System.out.println("Set 1: "
                       + set);

    // Creating another empty set
    Set<String>
        set2 = new HashSet<String>();

    // Use add() method to
    // add elements in the set
    set2.add("Geeks");
    set2.add("for");
    set2.add("Geeks");
    set2.add("10");
    set2.add("20");

    // prints the set
    System.out.println("Set 2: "
                       + set2);

    // Check if the set
    // contains same elements
    System.out.println(
        "\nDoes set 1 contains set 2?: "
        + set.containsAll(set2));
}

}

`

Output:

Set 1: [10, 20, Geeks, for] Set 2: [Geeks, for, 20, 10]

Does set 1 contains set 2?: true

Program 2:

Java `

// Java code to illustrate // boolean containsAll()

import java.util.*;

class SortedSetDemo { public static void main(String args[]) {

    // Creating an empty set
    SortedSet<String>
        set = new TreeSet<String>();

    // Use add() method to
    // add elements in the set
    set.add("Geeks");
    set.add("for");
    set.add("Geeks");

    // prints the set
    System.out.println("Set 1: "
                       + set);

    // Creating another empty set
    Set<String>
        set2 = new HashSet<String>();

    // Use add() method to
    // add elements in the set
    set2.add("10");
    set2.add("20");

    // prints the set
    System.out.println("Set 2: "
                       + set2);

    // Check if the set
    // contains same elements
    System.out.println(
        "\nDoes set 1 contains set 2: "
        + set.containsAll(set2));
}

}

`

Output:

Set 1: [Geeks, for] Set 2: [20, 10]

Does set 1 contains set 2: false

Reference: https://docs.oracle.com/javase/7/docs/api/java/util/Set.html#containsAll(java.util.Collection)