The array() method of java.nio.CharBuffer Class is used to return the char array that backs this buffer. Any modifications done to this buffer’s content will cause the returned array’s content also to be modified, and vice versa. hasArray() method is invoked before invoking this method in order to ensure that this buffer has an accessible backing array.
Syntax:
public final char[] 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:
Example 1:
// 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 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( 2 , 'b' );
cb.rewind();
// getting array from cb
// CharBuffer using array() method
char [] cbb = cb.array();
// printing the CharBuffer cb
System.out.println( "CharBuffer: "
+ Arrays.toString(cbb));
}
catch (IllegalArgumentException e) {
System.out.println( "IllegalArgumentException catched" );
}
catch (ReadOnlyBufferException e) {
System.out.println( "ReadOnlyBufferException catched" );
}
}
} |
CharBuffer: [a, , b, , , , , , , ]
Example 2:
// 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 cb
int capacity1 = 10 ;
// Declaring the capacity of the cb1
int capacity2 = 5 ;
// Creating the CharBuffer
try {
//
// cb
//
// creating object of CharBuffer cb
// and allocating size capacity
CharBuffer cb = CharBuffer.allocate(capacity1);
// putting the value in cb
cb.put( 'a' );
cb.put( 2 , 'b' );
cb.put( 3 , 'c' );
cb.rewind();
// print the CharBuffer
System.out.println( "CharBuffer cb: "
+ Arrays.toString(cb.array()));
//
// cb1
//
// creating object of CharBuffer cb1
// and allocating size capacity
CharBuffer cb1 = CharBuffer.allocate(capacity2);
// putting the value in cb1
cb1.put( 1 , 'd' );
cb1.put( 2 , 'e' );
cb1.rewind();
// print the CharBuffer
System.out.println( "\nCharBuffer cb1: "
+ Arrays.toString(cb1.array()));
// Creating a read-only copy of CharBuffer
// using asReadOnlyBuffer() method
CharBuffer readOnlycb = cb.asReadOnlyBuffer();
// print the CharBuffer
System.out.print( "\nReadOnlyBuffer CharBuffer: " );
while (readOnlycb.hasRemaining())
System.out.print(readOnlycb.get() + ", " );
// try to change readOnlycb
System.out.println( "\n\nTrying to get the array"
+ " from ReadOnlycb for editing" );
char [] cbarr = readOnlycb.array();
}
catch (IllegalArgumentException e) {
System.out.println( "IllegalArgumentException catched" );
}
catch (ReadOnlyBufferException e) {
System.out.println( "Exception thrown: " + e);
}
}
} |
CharBuffer cb: [a,, b, c,,,,,, ] CharBuffer cb1: [, d, e,, ] ReadOnlyBuffer CharBuffer: a,, b, c,,,,,,, Trying to get the array from ReadOnlycb for editing Exception thrown: java.nio.ReadOnlyBufferException