# DoubleBuffer compact() method in Java

The buffer can be compacted using the compact() method in the class java.nio.DoubleBuffer. This method does not require a parameter and it returns the new compacted DoubleBuffer with the same content as the original buffer. If the buffer is read-only, then the ReadOnlyBufferException is thrown.

A program that demonstrates this is given as follows −

## Example

Live Demo

import java.nio.*;
import java.util.*;
public class Demo {
public static void main(String[] args) {
int n = 5;
try {
DoubleBuffer buffer = DoubleBuffer.allocate(n);
buffer.put(1.2D);
buffer.put(3.9D);
buffer.put(7.5D);
System.out.println("The Original DoubleBuffer is: " + Arrays.toString(buffer.array()));
System.out.println("The position is: " + buffer.position());
System.out.println("The limit is: " + buffer.limit());
DoubleBuffer bufferCompact = buffer.compact();
System.out.println("The Compacted DoubleBuffer is: " + Arrays.toString(bufferCompact.array()));
System.out.println("The position is: " + bufferCompact.position());
System.out.println("The limit is: " + bufferCompact.limit());
} catch (IllegalArgumentException e) {
System.out.println("Error!!! IllegalArgumentException");
}
}
}

The output of the above program is as follows −

## Output

The Original DoubleBuffer is: [1.2, 3.9, 7.5, 0.0, 0.0]
The position is: 3
The limit is: 5

The Compacted DoubleBuffer is: [0.0, 0.0, 7.5, 0.0, 0.0]
The position is: 2
The limit is: 5
Samual Sam

Learning faster. Every day.