BitSet size() Method in Java with Examples

The size() Method of BitSet class in Java is used to know the size of this BitSet. This size is equal to the number of bits, each element has occupied in the BitSet. The maximum element in the set is the size – the first element

Syntax:

BitSet.hashCode()

Parameters: The method does not accept any parameters.

Return Value: The method returns the number of bits present in the BitSet.

Below programs are used to illustrate the working of BitSet.size() Method:
Program 1:

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

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(53);

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

        // Displaying the size
        System.out.println("The size is: "
                           + init_bitset.size());
    }
}

Output:

BitSet: {25, 31, 40, 53, 100}
The size is: 128

Program 2:

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

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

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

        // Displaying the hashcode
        System.out.println("The s iizes: "
                           + init_bitset.size());
    }
}

Output:

BitSet: {}
The size is: 64

Program 3:

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

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(400);

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

        // Displaying the hashcode
        System.out.println("The sizeis: " + init_bitset.size());
    }
}

Output:

BitSet: {400}
The size is: 448