FloatBuffer array() method in Java With Examples

Last Updated : 06 Dec, 2018

The array() method of java.nio.FloatBuffer Class is used to Return the float array that backs this buffer. Modifications to this buffer's content will cause the returned array's content to be modified, and vice versa. Invoke() the hasArray() method are used before invoking this method in order to ensure that this buffer has an accessible backing array Syntax :

public final float[] array()

Return Value: This method returns the array that backs this buffer. Throws: This method throws the ReadOnlyBufferException(If this buffer is backed by an array but is read-only) Below program illustrates the array() method: Examples 1:

Java

// Java program to demonstrate
// array() method

import java.nio.*;
import java.util.*;

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

        // Declaring the capacity of the FloatBuffer
        int capacity = 10;

        // Creating the FloatBuffer
        try {

            // creating object of floatbuffer
            // and allocating size capacity
            FloatBuffer fb = FloatBuffer.allocate(capacity);

            // putting the value in floatbuffer
            fb.put(8.56F);
            fb.put(2, 9.61F);
            fb.rewind();

            // getting array from fb FloatBuffer using array() method
            float[] fbb = fb.array();

            // printing the FloatBuffer fb
            System.out.println("FloatBuffer:  "
                               + Arrays.toString(fbb));
        }

        catch (IllegalArgumentException e) {

            System.out.println("IllegalArgumentException catched");
        }

        catch (ReadOnlyBufferException e) {

            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

Output:

FloatBuffer:  [8.56, 0.0, 9.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

Examples 2:

Java

// Java program to demonstrate
// array() method

import java.nio.*;
import java.util.*;

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

        // Declaring the capacity of the fb
        int capacity1 = 10;

        // Declaring the capacity of the fb1
        int capacity2 = 5;

        // Creating the FloatBuffer
        try {
            //
            // fb
            //
            // creating object of floatbuffer fb
            // and allocating size capacity
            FloatBuffer fb = FloatBuffer.allocate(capacity1);

            // putting the value in fb
            fb.put(9.56F);
            fb.put(2, 7.61F);
            fb.put(3, 4.61F);
            fb.rewind();

            // print the FloatBuffer
            System.out.println("FloatBuffer fb: "
                               + Arrays.toString(fb.array()));

            //
            // fb1
            //
            // creating object of floatbuffer fb1
            // and allocating size capacity
            FloatBuffer fb1 = FloatBuffer.allocate(capacity2);

            // putting the value in fb1
            fb1.put(1, 4.56F);
            fb1.put(2, 6.45F);
            fb1.rewind();

            // print the FloatBuffer
            System.out.println("\nFloatBuffer fb1:  "
                               + Arrays.toString(fb1.array()));

            // Creating a read-only copy of FloatBuffer
            // using asReadOnlyBuffer() method
            FloatBuffer readOnlyFb = fb.asReadOnlyBuffer();

            // print the FloatBuffer
            System.out.print("\nReadOnlyBuffer FloatBuffer: ");

            while (readOnlyFb.hasRemaining())
                System.out.print(readOnlyFb.get() + ", ");

            // try to change readOnlyFb
            System.out.println("\n\nTrying to get the array"
                               + " from ReadOnlyFb for editing");

            float[] fbarr = readOnlyFb.array();
        }
        catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException catched");
        }
        catch (ReadOnlyBufferException e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

Output:

FloatBuffer fb: [9.56, 0.0, 7.61, 4.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

FloatBuffer fb1:  [0.0, 4.56, 6.45, 0.0, 0.0]

ReadOnlyBuffer FloatBuffer: 9.56, 0.0, 7.61, 4.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 

Trying to get the array from ReadOnlyFb for editing
Exception thrown: java.nio.ReadOnlyBufferException