java.nio
Class CharBuffer

java.lang.Object
  java.nio.Buffer
      java.nio.CharBuffer

All Implemented Interfaces:

Appendable, CharSequence, Comparable<CharBuffer>, Readable

public abstract class CharBuffer
extends Buffer
implements Comparable<CharBuffer>, CharSequence, Readable, Appendable

Since:

1.4

Method Summary

static CharBuffer	allocate(int capacity) Allocates a new CharBuffer object with a given capacity.
CharBuffer	append(char c) append appends a single character to this.
CharBuffer	append(CharSequence cs) append appends the characters from the given sequence to this.
CharBuffer	append(CharSequence cs, int start, int end) append appends a subrange of the characters from the given squence to this.
char[]	array() Returns the char array that backs this buffer.
int	arrayOffset() Returns the offset within this buffer's backing array of the first element.
abstract CharBuffer	asReadOnlyBuffer() Creates a new read-only CharBuffer that shares this buffer's content.
char	charAt(int index) Returns the character at position() + index.
abstract CharBuffer	compact() Compacts this buffer.
int	compareTo(CharBuffer other) Compares two CharBuffer objects.
abstract CharBuffer	duplicate() Creates a new CharBuffer that shares this buffer's content.
boolean	equals(Object obj) Checks if this buffer is equal to obj.
abstract char	get() Reads the char at this buffer's current position, and then increments the position.
CharBuffer	get(char[] dst) This method transfers chars from this buffer into the given destination array.
CharBuffer	get(char[] dst, int offset, int length) This method transfers chars from this buffer into the given destination array.
abstract char	get(int index) Absolute get method.
boolean	hasArray() Tells whether ot not this buffer is backed by an accessible char array.
int	hashCode() Calculates a hash code for this buffer.
abstract boolean	isDirect() Tells wether or not this buffer is direct.
int	length() Returns the length of the remaining chars in this buffer.
abstract ByteOrder	order() Returns the byte order of this buffer.
abstract CharBuffer	put(char b) Writes the char at this buffer's current position, and then increments the position.
CharBuffer	put(char[] src) Writes the content of the the char array src into the buffer.
CharBuffer	put(char[] src, int offset, int length) Writes the content of the the char array src into the buffer.
CharBuffer	put(CharBuffer src) Writes the content of the the CharBUFFER src into the buffer.
abstract CharBuffer	put(int index, char b) Absolute put method.
CharBuffer	put(String str) Relative put method.
CharBuffer	put(String str, int start, int length) Relative put method.
int	read(CharBuffer buffer) Read characters into a given CharBuffer.
abstract CharBuffer	slice() Creates a new CharBuffer whose content is a shared subsequence of this buffer's content.
abstract CharSequence	subSequence(int start, int length) Creates a new character buffer that represents the specified subsequence of this buffer, relative to the current position.
String	toString() Returns the remaining content of the buffer as a string.
static CharBuffer	wrap(char[] array) Wraps a char array into a CharBuffer object.
static CharBuffer	wrap(char[] array, int offset, int length) Wraps a char array into a CharBuffer object.
static CharBuffer	wrap(CharSequence seq) Wraps a character sequence into a CharBuffer object.
static CharBuffer	wrap(CharSequence seq, int start, int end) Wraps a character sequence into a CharBuffer object.

Methods inherited from class java.nio.Buffer

capacity, clear, flip, hasRemaining, isReadOnly, limit, limit, mark, position, position, remaining, reset, rewind

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

allocate

public static CharBuffer allocate(int capacity)

Allocates a new CharBuffer object with a given capacity.

wrap

public static final CharBuffer wrap(char[] array,
                                    int offset,
                                    int length)

Wraps a char array into a CharBuffer object.

Parameters:

array - the array to wrap

offset - the offset of the region in the array to wrap

length - the length of the region in the array to wrap

Returns:

a new CharBuffer object

Throws:

IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold

wrap

public static final CharBuffer wrap(CharSequence seq)

Wraps a character sequence into a CharBuffer object.

Parameters:

seq - the sequence to wrap

Returns:

a new CharBuffer object

wrap

public static final CharBuffer wrap(CharSequence seq,
                                    int start,
                                    int end)

Wraps a character sequence into a CharBuffer object.

Parameters:

seq - the sequence to wrap

start - the index of the first character to wrap

end - the index of the first character not to wrap

Returns:

a new CharBuffer object

Throws:

IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold

wrap

public static final CharBuffer wrap(char[] array)

Wraps a char array into a CharBuffer object.

Parameters:

array - the array to wrap

Returns:

a new CharBuffer object

get

public CharBuffer get(char[] dst,
                      int offset,
                      int length)

This method transfers chars from this buffer into the given destination array. Before the transfer, it checks if there are fewer than length chars remaining in this buffer.

Parameters:

dst - The destination array

offset - The offset within the array of the first char to be written; must be non-negative and no larger than dst.length.

length - The maximum number of bytes to be written to the given array; must be non-negative and no larger than dst.length - offset.

Throws:

BufferUnderflowException - If there are fewer than length chars remaining in this buffer.

IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold.

read

public int read(CharBuffer buffer)
         throws IOException

Description copied from interface: Readable

Read characters into a given CharBuffer.

Specified by:

read in interface Readable

Parameters:

buffer - the buffer to store the characters in

Returns:

the number of character read, -1 for end of file.

Throws:

IOException - if an I/O error occured

Since:

1.5

get

public CharBuffer get(char[] dst)

This method transfers chars from this buffer into the given destination array.

Parameters:

dst - The byte array to write into.

Throws:

BufferUnderflowException - If there are fewer than dst.length chars remaining in this buffer.

put

public CharBuffer put(CharBuffer src)

Writes the content of the the CharBUFFER src into the buffer. Before the transfer, it checks if there is fewer than src.remaining() space remaining in this buffer.

Parameters:

src - The source data.

Throws:

BufferOverflowException - If there is insufficient space in this buffer for the remaining chars in the source buffer.

IllegalArgumentException - If the source buffer is this buffer.

ReadOnlyBufferException - If this buffer is read-only.

put

public CharBuffer put(char[] src,
                      int offset,
                      int length)

Writes the content of the the char array src into the buffer. Before the transfer, it checks if there is fewer than length space remaining in this buffer.

Parameters:

src - The array to copy into the buffer.

offset - The offset within the array of the first byte to be read; must be non-negative and no larger than src.length.

length - The number of bytes to be read from the given array; must be non-negative and no larger than src.length - offset.

Throws:

BufferOverflowException - If there is insufficient space in this buffer for the remaining chars in the source array.

IndexOutOfBoundsException - If the preconditions on the offset and length parameters do not hold

ReadOnlyBufferException - If this buffer is read-only.

put

public final CharBuffer put(char[] src)

Writes the content of the the char array src into the buffer.

Parameters:

src - The array to copy into the buffer.

Throws:

BufferOverflowException - If there is insufficient space in this buffer for the remaining chars in the source array.

ReadOnlyBufferException - If this buffer is read-only.

hasArray

public final boolean hasArray()

Tells whether ot not this buffer is backed by an accessible char array.

Specified by:

hasArray in class Buffer

Returns:

true if this buffer can provide a backing array, false otherwise

array

public final char[] array()

Returns the char array that backs this buffer.

Specified by:

array in class Buffer

Returns:

the backing array of this buffer

Throws:

ReadOnlyBufferException - If this buffer is read-only.

UnsupportedOperationException - If this buffer is not backed by an accessible array.

arrayOffset

public final int arrayOffset()

Returns the offset within this buffer's backing array of the first element.

Specified by:

arrayOffset in class Buffer

Returns:

the offset into the backing array at which the buffer content starts

Throws:

ReadOnlyBufferException - If this buffer is read-only.

UnsupportedOperationException - If this buffer is not backed by an accessible array.

hashCode

public int hashCode()

Calculates a hash code for this buffer. This is done with int arithmetic, where ** represents exponentiation, by this formula:
s[position()] + 31 + (s[position()+1] + 30)*31**1 + ... + (s[limit()-1]+30)*31**(limit()-1). Where s is the buffer data. Note that the hashcode is dependent on buffer content, and therefore is not useful if the buffer content may change.

Overrides:

hashCode in class Object

Returns:

a hash code value.

equals

public boolean equals(Object obj)

Checks if this buffer is equal to obj.

Overrides:

equals in class Object

Parameters:

obj - the other object.

Returns:

if this and other are considered equal.

compareTo

public int compareTo(CharBuffer other)

Compares two CharBuffer objects.

Specified by:

compareTo in interface Comparable<CharBuffer>

Parameters:

other - the other object

Returns:

a value <0 if this < o, 0 if this == o and a value > 0 if this > o.

Throws:

ClassCastException - If obj is not an object derived from CharBuffer.

order

public abstract ByteOrder order()

Returns the byte order of this buffer.

get

public abstract char get()

Reads the char at this buffer's current position, and then increments the position.

Throws:

BufferUnderflowException - If there are no remaining chars in this buffer.

put

public abstract CharBuffer put(char b)

Writes the char at this buffer's current position, and then increments the position.

Throws:

BufferOverflowException - If there no remaining chars in this buffer.

ReadOnlyBufferException - If this buffer is read-only.

get

public abstract char get(int index)

Absolute get method.

Throws:

IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit.

put

public abstract CharBuffer put(int index,
                               char b)

Absolute put method.

Throws:

IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit.

ReadOnlyBufferException - If this buffer is read-only.

compact

public abstract CharBuffer compact()

Compacts this buffer.

Throws:

ReadOnlyBufferException - If this buffer is read-only.

isDirect

public abstract boolean isDirect()

Tells wether or not this buffer is direct.

Specified by:

isDirect in class Buffer

Returns:

true when this buffer is direct, false otherwise

slice

public abstract CharBuffer slice()

Creates a new CharBuffer whose content is a shared subsequence of this buffer's content.

duplicate

public abstract CharBuffer duplicate()

Creates a new CharBuffer that shares this buffer's content.

asReadOnlyBuffer

public abstract CharBuffer asReadOnlyBuffer()

Creates a new read-only CharBuffer that shares this buffer's content.

toString

public String toString()

Returns the remaining content of the buffer as a string.

Specified by:

toString in interface CharSequence

Overrides:

toString in class Object

Returns:

a string identifying this object.

length

public final int length()

Returns the length of the remaining chars in this buffer.

Specified by:

length in interface CharSequence

Returns:

the number of chars in this sequence.

subSequence

public abstract CharSequence subSequence(int start,
                                         int length)

Creates a new character buffer that represents the specified subsequence of this buffer, relative to the current position.

Specified by:

subSequence in interface CharSequence

Parameters:

start - the start position.

length - the end position.

Returns:

a subsequence

Throws:

IndexOutOfBoundsException - If the preconditions on start and end do not hold.

put

public CharBuffer put(String str,
                      int start,
                      int length)

Relative put method.

Throws:

BufferOverflowException - If there is insufficient space in this buffer.

IndexOutOfBoundsException - If the preconditions on the start and end parameters do not hold.

ReadOnlyBufferException - If this buffer is read-only.

put

public final CharBuffer put(String str)

Relative put method.

Throws:

BufferOverflowException - If there is insufficient space in this buffer.

ReadOnlyBufferException - If this buffer is read-only.

charAt

public final char charAt(int index)

Returns the character at position() + index.

Specified by:

charAt in interface CharSequence

Parameters:

index - the position

Returns:

the character at this position.

Throws:

IndexOutOfBoundsException - If index is negative not smaller than remaining().

append

public CharBuffer append(char c)

Description copied from interface: Appendable

append appends a single character to this.

Specified by:

append in interface Appendable

Parameters:

c - the character to append.

Returns:

a reference to this instance.

Since:

1.5

append

public CharBuffer append(CharSequence cs)

Description copied from interface: Appendable

append appends the characters from the given sequence to this.

Specified by:

append in interface Appendable

Parameters:

cs - the character sequence, may be null to append the sequence "null".

Returns:

a reference to this instance.

Since:

1.5

append

public CharBuffer append(CharSequence cs,
                         int start,
                         int end)

Description copied from interface: Appendable

append appends a subrange of the characters from the given squence to this.

Specified by:

append in interface Appendable

Parameters:

cs - the character sequence, may be null to append the sequence "null".

start - the start position.

end - the end position.

Returns:

a reference to this instance.

Since:

1.5