AbstractCollection contains() Method in Java with Examples (original) (raw)

Last Updated : 12 Jun, 2023

The contains() method of Java AbstractCollection is used to check whether an element is present in a Collection or not. It takes the element as a parameter and returns True if the element is present in the collection.
Syntax:

AbstractCollection.contains(Object element)

Parameters: The parameter element is of type Collection. This parameter refers to the element whose occurrence is needed to be checked in the collection.
Return Value: The method returns True if the element is present in the Collection otherwise it returns False.
Below programs illustrate the Java.util.AbstractCollection.contains() method:
Program 1:

Java `

// Java code to illustrate boolean contains()

import java.util.*; import java.util.AbstractCollection;

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

    // Creating an empty Collection
    AbstractCollection<String>
        abs = new LinkedList<String>();

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

    // Displaying the collection
    System.out.println("Abstract Collection:"
                       + abs);

    // Check if the collection contains "Hello"
    System.out.println("\nDoes the Collection"
                       + " contains 'Hello': "
                       + abs.contains("Hello"));

    // Check if the Collection contains "20"
    System.out.println("Does the collection"
                       + " contains '20': "
                       + abs.contains("20"));

    // Check if the Collection contains "Geeks"
    System.out.println("Does the Collection"
                       + " contains 'Geeks': "
                       + abs.contains("Geeks"));
}

}

`

Output:

Abstract Collection:[Geeks, for, Geeks, 10, 20]

Does the Collection contains 'Hello': false Does the collection contains '20': true Does the Collection contains 'Geeks': true

Program 2:

Java `

// Java code to illustrate boolean contains()

import java.util.*; import java.util.AbstractCollection;

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

    // Creating an empty Collection
    AbstractCollection<String>
        abs = new TreeSet<String>();

    // Use add() method to add
    // elements in the collection
    abs.add("Geeks");
    abs.add("for");
    abs.add("Geeks");
    abs.add("TreeSet");
    abs.add("20");

    // Displaying the collection
    System.out.println("Abstract Collection:"
                       + abs);

    // Check if the collection contains "TreeSet"
    System.out.println("\nDoes the Collection "
                       + "contains 'TreeSet': "
                       + abs.contains("TreeSet"));

    // Check if the collection contains "Hello"
    System.out.println("\nDoes the Collection"
                       + " contains 'Hello': "
                       + abs.contains("Hello"));

    // Check if the Collection contains "20"
    System.out.println("Does the collection"
                       + " contains '20': "
                       + abs.contains("20"));

    // Check if the Collection contains "Geeks"
    System.out.println("Does the Collection"
                       + " contains 'Geeks': "
                       + abs.contains("Geeks"));
}

}

`

Output:

Abstract Collection:[20, Geeks, TreeSet, for]

Does the Collection contains 'TreeSet': true

Does the Collection contains 'Hello': false Does the collection contains '20': true Does the Collection contains 'Geeks': true