El método compact() de java.nio.CharBuffer Class se usa para compactar el búfer dado.
Los valores entre la posición actual del búfer y su límite se copian al principio del búfer. Luego, la posición del búfer se establece en n+1 y su límite se establece en su capacidad. La posición del búfer se establece en el número de flotantes copiados.
Sintaxis:
public abstract CharBuffer compact()
Valor devuelto: este método devuelve el nuevo CharBuffer con el mismo contenido que el de este búfer.
Excepción: este método lanza ReadOnlyBufferException , si este búfer es de solo lectura.
El siguiente programa ilustra el método compact() :
Ejemplo 1:
// Java program to demonstrate
// compact() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the CharBuffer
int capacity = 10;
// Creating the CharBuffer
// creating object of Intbuffer
// and allocating size capacity
CharBuffer ic = CharBuffer.allocate(capacity);
// putting the value in Intbuffer
ic.put('a');
ic.put('b');
ic.put('c');
// print the CharBuffer
System.out.println("Original CharBuffer: "
+ Arrays.toString(ic.array()));
System.out.println("Position: " + ic.position());
System.out.println("limit: " + ic.limit());
// Creating a compacted CharBuffer of same CharBuffer
// using compact() method
CharBuffer CharBuffer = ic.compact();
// print the CharBuffer
System.out.println("\nCompacted CharBuffer: "
+ Arrays.toString(CharBuffer.array()));
System.out.println("Position: " + CharBuffer.position());
System.out.println("limit: " + CharBuffer.limit());
// putting the value in compacted Intbuffer
CharBuffer.put('g');
// print the CharBuffer
System.out.println("\nUpdated Compacted CharBuffer: "
+ Arrays.toString(CharBuffer.array()));
System.out.println("Position: " + CharBuffer.position());
System.out.println("limit: " + CharBuffer.limit());
}
}
Producción:
Original CharBuffer: [a, b, c, , , , , , , ] Position: 3 limit: 10 Compacted CharBuffer: [, , , , , , , , , ] Position: 7 limit: 10 Updated Compacted CharBuffer: [, , , , , , , g, , ] Position: 8 limit: 10
Ejemplo 2:
// Java program to demonstrate
// compact() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the CharBuffer
int capacity = 10;
// Creating the CharBuffer
try {
// creating object of CharBuffer
// and allocating size capacity
CharBuffer cb = CharBuffer.allocate(capacity);
// putting the value in CharBuffer
cb.put('a');
cb.put('b');
cb.put('b');
cb.rewind();
// Creating a read-only copy of CharBuffer
// using asReadOnlyBuffer() method
CharBuffer cb1 = cb.asReadOnlyBuffer();
// print the ReadOnlyBuffer
System.out.print("ReadOnlyBuffer CharBuffer: ");
while (cb1.hasRemaining())
System.out.print(cb1.get() + ", ");
System.out.println("");
// print the Position of CharBuffer cb
System.out.println("\nPosition: " + cb.position());
// print the Limit of CharBuffer cb
System.out.println("\nlimit: " + cb.limit());
// Creating a compacted CharBuffer of same ReadOnlyBuffer
// using compact() method
System.out.println("\nTrying to compact the ReadOnlyBuffer cb1");
CharBuffer CharBuffer = cb1.compact();
}
catch (IllegalArgumentException e) {
System.out.println("Exception throws " + e);
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws " + e);
}
}
}
Producción:
ReadOnlyBuffer CharBuffer: a, b, b, , , , , , , , Position: 0 limit: 10 Trying to compact the ReadOnlyBuffer cb1 Exception throws java.nio.ReadOnlyBufferException