ByteBuffer getLong() method in Java with Examples
getLong()
The getLong() method of java.nio.ByteBuffer class is used to read the next eight bytes at this buffer’s current position, composing them into a long value according to the current byte order, and then increments the position by eight.
Syntax:
public abstract long getLong()
Return Value: This method returns the long value at the buffer’s current position.
Throws: This method throws BufferUnderflowException – If there are fewer than four bytes remaining in this buffer.
Below are the examples to illustrate the getLong() method:
Examples 1:
// Java program to demonstrate// getLong() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 16; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the long value in the bytebuffer bb.asLongBuffer() .put(1233003) .put(2292292); // rewind the Bytebuffer bb.rewind(); // print the ByteBuffer System.out.println("Original ByteBuffer: "); for (int i = 1; i <= capacity / 8; i++) System.out.print(bb.getLong() + " "); // rewind the Bytebuffer bb.rewind(); // Reads the long at this buffer's current position // using getLong() method long value = bb.getLong(); // print the long value System.out.println("\n\nByte Value: " + value); // Reads the long at this buffer's next position // using getLong() method long value1 = bb.getLong(); // print the long value System.out.print("\nNext Byte Value: " + value1); } catch (BufferUnderflowException e) { System.out.println("\nException Thrown : " + e); } }} |
Output:
Original ByteBuffer: 1233003 2292292 Byte Value: 1233003 Next Byte Value: 2292292
Examples 2:
// Java program to demonstrate// getLong() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 16; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the long value in the bytebuffer bb.asLongBuffer() .put(1233003) .put(2292292); // rewind the Bytebuffer bb.rewind(); // print the ByteBuffer System.out.println("Original ByteBuffer: "); for (int i = 1; i <= capacity / 8; i++) System.out.print(bb.getLong() + " "); // rewind the Bytebuffer bb.rewind(); // Reads the long at this buffer's current position // using getLong() method long value = bb.getLong(); // print the long value System.out.println("\n\nByte Value: " + value); // Reads the long at this buffer's next position // using getLong() method long value1 = bb.getLong(); // print the long value System.out.print("\nNext Byte Value: " + value1); // Reads the long at this buffer's next position // using getLong() method long value2 = bb.getLong(); } catch (BufferUnderflowException e) { System.out.println("\nthere are fewer than " + "eight bytes remaining in this buffer"); System.out.println("Exception Thrown : " + e); } }} |
Output:
Original ByteBuffer: 1233003 2292292 Byte Value: 1233003 Next Byte Value: 2292292 there are fewer than eight bytes remaining in this buffer Exception Thrown : java.nio.BufferUnderflowException
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/ByteBuffer.html#getLong–
getLong(int index)
The getLong(int index) method of ByteBuffer is used to read four bytes at the given index, composing them into a float value according to the current byte order.
Syntax:
public abstract long getLong(int index)
Parameters: This method takes index (The index from which the Byte will be read) as a parameter.
Return Value: This method returns the long value at the given index.
Exception: This method throws IndexOutOfBoundsException. If index is negative or not smaller than the buffer’s limit this exception is thrown.
Below are the examples to illustrate the getLong(int index) method:
Examples 1:
// Java program to demonstrate// getLong() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 16; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the long value in the bytebuffer bb.asLongBuffer() .put(1233003) .put(2292292); // rewind the Bytebuffer bb.rewind(); // print the ByteBuffer System.out.println("Original ByteBuffer: "); for (int i = 1; i <= capacity / 8; i++) System.out.print(bb.getLong() + " "); // rewind the Bytebuffer bb.rewind(); // Reads the long at this buffer's current position // using getLong() method long value = bb.getLong(0); // print the long value System.out.println("\n\nByte Value: " + value); // Reads the long at this buffer's next position // using getLong() method long value1 = bb.getLong(8); // print the long value System.out.print("\nNext Byte Value: " + value1); } catch (IndexOutOfBoundsException e) { System.out.println("\nindex is negative or " + "smaller than the buffer's limit, " + "minus seven"); System.out.println("Exception Thrown : " + e); } }} |
Output:
Original ByteBuffer: 1233003 2292292 Byte Value: 1233003 Next Byte Value: 2292292
Examples 2:
// Java program to demonstrate// getLong() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 16; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the long value in the bytebuffer bb.asLongBuffer() .put(1233003) .put(2292292); // rewind the Bytebuffer bb.rewind(); // print the ByteBuffer System.out.println("Original ByteBuffer: "); for (int i = 1; i <= capacity / 8; i++) System.out.print(bb.getLong() + " "); // rewind the Bytebuffer bb.rewind(); // Reads the long at this buffer's current position // using getLong() method long value = bb.getLong(0); // print the long value System.out.println("\n\nByte Value: " + value); // Reads the long at this buffer's next position // using getLong() method long value1 = bb.getLong(11); // print the long value System.out.print("\nNext Byte Value: " + value1); } catch (IndexOutOfBoundsException e) { System.out.println("\nindex is negative or" + " smaller than the buffer's limit, " + "minus seven"); System.out.println("Exception Thrown : " + e); } }} |
Output:
Original ByteBuffer: 1233003 2292292 Byte Value: 1233003 index is negative or smaller than the buffer's limit, minus seven Exception Thrown : java.lang.IndexOutOfBoundsException
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/ByteBuffer.html#getLong-int-
