BitSet stream() Method in Java with Examples

The stream() method of Java BitSet class is used to return a stream of indices for every bit contained in the BitSet. The indices are returned in increasing order. The size of the stream is the number of bits in the set state of the BitSet, which is equal to the value returned by the cardinality() method.

Syntax:

public IntStream stream()

Parameters: The method does not take any parameters.
Return Value: The method returns a stream of indices for every bit contained in the BitSet.

Below programs illustrate the working of java.util.BitSet.stream() method:
Program 1:

// Java code to illustrate stream()
import java.util.*;
import java.util.stream.IntStream;

public class BitSet_Demo {
    public static void main(String args[])
    {
        // Creating an empty BitSet
        BitSet init_bitset = new BitSet();

        // Use set() method to add elements into the Set
        init_bitset.set(10);
        init_bitset.set(20);
        init_bitset.set(30);
        init_bitset.set(40);
        init_bitset.set(50);

        // Displaying the BitSet
        System.out.println("BitSet: " + init_bitset);

        // Creating an IntStream
        IntStream indice_Stream = init_bitset.stream();

        // Displaying the working
        System.out.println("The BitSet: " + init_bitset);
        System.out.println("The stream of indices: "
                           + indice_Stream);
        System.out.println("The size of the stream: "
                           + indice_Stream.count());
    }
}

Output:

BitSet: {10, 20, 30, 40, 50}
The BitSet: {10, 20, 30, 40, 50}
The stream of indices: java.util.stream.IntPipeline$Head@4eec7777
The size of the stream: 5

Program 2:

// Java code to illustrate stream()
import java.util.*;
import java.util.stream.IntStream;

public class BitSet_Demo {
    public static void main(String args[])
    {
        // Creating an empty BitSet
        BitSet init_bitset = new BitSet();

        // Use set() method to add elements into the Set
        init_bitset.set(40);
        init_bitset.set(25);
        init_bitset.set(31);
        init_bitset.set(100);
        init_bitset.set(121);
        init_bitset.set(400);
        init_bitset.set(2);
        init_bitset.set(15);
        init_bitset.set(106);
        init_bitset.set(55);

        // Displaying the BitSet
        System.out.println("BitSet: " + init_bitset);

        // Creating an IntStream
        IntStream indice_Stream = init_bitset.stream();

        // Displaying the working
        System.out.println("The BitSet: " + init_bitset);
        System.out.println("The stream of indices: "
                           + indice_Stream);
        System.out.println("The size of the stream: "
                           + indice_Stream.count());
    }
}

Output:

BitSet: {2, 15, 25, 31, 40, 55, 100, 106, 121, 400}
The BitSet: {2, 15, 25, 31, 40, 55, 100, 106, 121, 400}
The stream of indices: java.util.stream.IntPipeline$Head@4eec7777
The size of the stream: 10