The containsAll() method of Java AbstractSet 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.
Below programs illustrate the AbstractSet.conatinsAll() method:
Program 1:
// Java code to illustrate// AbstractSet containsAll()  import java.util.*;  class AbstractSetDemo {    public static void main(String args[])    {          // Creating an empty set        AbstractSet<String>            abs = new TreeSet<String>();          // Use add() method to        // add elements in the set        abs.add("Geeks");        abs.add("for");        abs.add("Geeks");        abs.add("10");        abs.add("20");          // prints the set        System.out.println("AbstractSet 1: "                           + abs);          // Creating another empty set        AbstractSet<String>            abs2 = new TreeSet<String>();          // Use add() method to        // add elements in the set        abs2.add("Geeks");        abs2.add("for");        abs2.add("Geeks");        abs2.add("10");        abs2.add("20");          // prints the set        System.out.println("AbstractSet 2: "                           + abs2);          // Check if the set        // contains same elements        System.out.println("\nDoes set 1 contains set 2: "                           + abs.containsAll(abs2));    }} |
Output:
AbstractSet 1: [10, 20, Geeks, for] AbstractSet 2: [10, 20, Geeks, for] Does set 1 contains set 2: true
Program 2:
// Java code to illustrate boolean containsAll()  import java.util.*;  class AbstractSetDemo {    public static void main(String args[])    {          // Creating an empty set        AbstractSet<String>            abs = new TreeSet<String>();          // Use add() method to        // add elements in the set        abs.add("Geeks");        abs.add("for");        abs.add("Geeks");          // prints the set        System.out.println("AbstractSet 1: "                           + abs);          // Creating another empty set        AbstractSet<String>            abs2 = new TreeSet<String>();          // Use add() method to        // add elements in the set        abs2.add("10");        abs2.add("20");          // prints the set        System.out.println("AbstractSet 2: "                           + abs2);          // Check if the set        // contains same elements        System.out.println("\nDoes set 1 contains set 2: "                           + abs.containsAll(abs2));    }} |
Output:
AbstractSet 1: [Geeks, for] AbstractSet 2: [10, 20] Does set 1 contains set 2: false
