The allocate() method of java.nio.DoubleBuffer Class is used to allocate a new double buffer next to the existing buffer. The new buffer’s position will be zero. Its limit will be its capacity. Its mark will be undefined. And each of its elements will be initialized to zero. It will have a backing array, and its array offset will be zero.
Syntax:
public static DoubleBuffer allocate(int capacity)
Parameter: This method takes the new buffer’s capacity, in double, as a parameter.
Return Value: This method returns the new double buffer.
Exception: This method throws the IllegalArgumentException if the capacity is a negative integer.
Below program illustrates the allocate() method:
Examples 1:
Java
// Java program to demonstrate// allocate() methodimport java.nio.*;import java.util.*;public class GFG { public static void main(String[] args) { // Declaring the capacity of the DoubleBuffer int capacity = 10; // Creating the DoubleBuffer // creating object of Doublebuffer // and allocating size capacity DoubleBuffer db = DoubleBuffer.allocate(capacity); // putting the value in Doublebuffer db.put(8.56F); db.put(2, 9.61F); System.out.println("DoubleBuffer: " + Arrays.toString(db.array())); }} |
Output:
DoubleBuffer: [8.5600004196167, 0.0, 9.609999656677246, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
Examples 2: To demonstrate IllegalArgumentException
Java
// Java program to demonstrate// allocate() methodimport java.nio.*;import java.util.*;public class GFG { public static void main(String[] args) { // Declaring the capacity of the DoubleBuffer // by negative integer int capacity = -10; // Creating the DoubleBuffer try { // creating object of Doublebuffer // and allocating size with negative integer System.out.println("Trying to allocate a negative integer"); DoubleBuffer db = DoubleBuffer.allocate(capacity); } catch (IllegalArgumentException e) { System.out.println("Exception thrown: " + e); } }} |
Output
Trying to allocate a negative integer Exception thrown: java.lang.IllegalArgumentException: capacity < 0: (-10 < 0)
