java.nio
Class LongBuffer

java.lang.Object
  java.nio.Buffer
      java.nio.LongBuffer

All Implemented Interfaces:

Comparable<LongBuffer>

Direct Known Subclasses:

LongArrayBuffer, LongToByteBufferAdapter

public abstract class LongBuffer
extends Buffer
implements Comparable<LongBuffer>

A buffer of longs.

A long buffer can be created in either of the following ways:

• Allocate a new long array and create a buffer based on it;
• Wrap an existing long array to create a new buffer;
• Use ByteBuffer.asLongBuffer to create a long buffer based on a byte buffer.

Field Summary

Fields inherited from class java.nio.Buffer

_elementSizeShift, capacity, limit, mark, position, UNSET_MARK

Constructor Summary

LongBuffer(int capacity)
Constructs a LongBuffer with given capacity.

Method Summary

(package private) Object	_array() Returns the array associated with this buffer, or null if none exists.
(package private) int	_arrayOffset() Returns the offset into the backing array, if one exists, otherwise 0.
static LongBuffer	allocate(int capacity) Creates a long buffer based on a new allocated long array.
long[]	array() Returns the long array which this buffer is based on, if there's one.
int	arrayOffset() Returns the offset of the long array which this buffer is based on, if there's one.
abstract LongBuffer	asReadOnlyBuffer() Returns a readonly buffer that shares content with this buffer.
abstract LongBuffer	compact() Compacts this long buffer.
int	compareTo(LongBuffer otherBuffer) Compare the remaining longs of this buffer to another long buffer's remaining longs.
abstract LongBuffer	duplicate() Returns a duplicated buffer that shares content with this buffer.
boolean	equals(Object other) Tests whether this long buffer equals to another object.
abstract long	get() Returns the long at the current position and increase the position by 1.
abstract long	get(int index) Returns a long at the specified index, and the position is not changed.
LongBuffer	get(long[] dest) Reads longs from the current position into the specified long array and increase the position by the number of longs read.
LongBuffer	get(long[] dest, int off, int len) Reads longs from the current position into the specified long array, starting from the specified offset, and increase the position by the number of longs read.
boolean	hasArray() Returns whether this buffer is based on a long array and is read/write.
int	hashCode() Hash code is calculated from the remaining longs.
abstract boolean	isDirect() Returns true if this buffer is direct.
abstract ByteOrder	order() Returns the byte order used by this buffer when converting longs from/to bytes.
(package private) abstract long[]	protectedArray() Child class implements this method to realize array().
(package private) abstract int	protectedArrayOffset() Child class implements this method to realize arrayOffset().
(package private) abstract boolean	protectedHasArray() Child class implements this method to realize hasArray().
abstract LongBuffer	put(int index, long l) Write a long to the specified index of this buffer and the position is not changed.
abstract LongBuffer	put(long l) Writes the given long to the current position and increase the position by 1.
LongBuffer	put(long[] src) Writes longs in the given long array to the current position and increase the position by the number of longs written.
LongBuffer	put(long[] src, int off, int len) Writes longs in the given long array, starting from the specified offset, to the current position and increase the position by the number of longs written.
LongBuffer	put(LongBuffer src) Writes all the remaining longs of the src long buffer to this buffer's current position, and increase both buffers' position by the number of longs copied.
abstract LongBuffer	slice() Returns a sliced buffer that shares content with this buffer.
String	toString() Returns a string represents the state of this long buffer.
static LongBuffer	wrap(long[] array) Creates a new long buffer by wrapping the given long array.
static LongBuffer	wrap(long[] array, int start, int len) Creates new a long buffer by wrapping the given long array.

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

Constructor Detail

LongBuffer

LongBuffer(int capacity)

Constructs a LongBuffer with given capacity.

Parameters:

capacity - The capacity of the buffer

Method Detail

allocate

public static LongBuffer allocate(int capacity)

Creates a long buffer based on a new allocated long array.

Parameters:

capacity - The capacity of the new buffer

Returns:

The created long buffer

Throws:

IllegalArgumentException - If capacity is less than zero

wrap

public static LongBuffer wrap(long[] array)

Creates a new long buffer by wrapping the given long array.

Calling this method has the same effect as wrap(array, 0, array.length).

Parameters:

array - The long array which the new buffer will be based on

Returns:

The created long buffer

wrap

public static LongBuffer wrap(long[] array,
                              int start,
                              int len)

Creates new a long buffer by wrapping the given long array.

The new buffer's position will be start, limit will be start + len, capacity will be the length of the array.

Parameters:

array - The long array which the new buffer will be based on

start - The start index, must be no less than zero and no greater than array.length

len - The length, must be no less than zero and no greater than array.length - start

Returns:

The created long buffer

Throws:

IndexOutOfBoundsException - If either start or len is invalid

array

public final long[] array()

Returns the long array which this buffer is based on, if there's one.

Returns:

The long array which this buffer is based on

Throws:

ReadOnlyBufferException - If this buffer is based on an array, but it is readonly

UnsupportedOperationException - If this buffer is not based on an array

arrayOffset

public final int arrayOffset()

Returns the offset of the long array which this buffer is based on, if there's one.

The offset is the index of the array corresponds to the zero position of the buffer.

Returns:

The offset of the long array which this buffer is based on

Throws:

ReadOnlyBufferException - If this buffer is based on an array, but it is readonly

UnsupportedOperationException - If this buffer is not based on an array

_array

Object _array()

Description copied from class: Buffer

Returns the array associated with this buffer, or null if none exists. Each typed subclass (ByteBuffer, CharBuffer, etc.) overrides this method to call its array() method with appropriate checks.

Overrides:

_array in class Buffer

Returns:

a primitive array or null

_arrayOffset

int _arrayOffset()

Description copied from class: Buffer

Returns the offset into the backing array, if one exists, otherwise 0. Each typed subclass (ByteBuffer, CharBuffer, etc.) overrides this method to call its arrayOffset() method with appropriate checks.

Overrides:

_arrayOffset in class Buffer

Returns:

the array offset, or 0

asReadOnlyBuffer

public abstract LongBuffer asReadOnlyBuffer()

Returns a readonly buffer that shares content with this buffer.

The returned buffer is guaranteed to be a new instance, even this buffer is readonly itself. The new buffer's position, limit, capacity and mark are the same as this buffer.

The new buffer shares content with this buffer, which means this buffer's change of content will be visible to the new buffer. The two buffer's position, limit and mark are independent.

Returns:

A readonly version of this buffer.

compact

public abstract LongBuffer compact()

Compacts this long buffer.

The remaining longs will be moved to the head of the buffer, staring from position zero. Then the position is set to remaining(); the limit is set to capacity; the mark is cleared.

Returns:

This buffer

Throws:

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

compareTo

public int compareTo(LongBuffer otherBuffer)

Compare the remaining longs of this buffer to another long buffer's remaining longs.

Specified by:

compareTo in interface Comparable<LongBuffer>

Parameters:

otherBuffer - Another long buffer

Returns:

a negative value if this is less than other; 0 if this equals to other; a positive value if this is greater than other

Throws:

ClassCastException - If other is not a long buffer

duplicate

public abstract LongBuffer duplicate()

Returns a duplicated buffer that shares content with this buffer.

The duplicated buffer's position, limit, capacity and mark are the same as this buffer. The duplicated buffer's readonly property and byte order are same as this buffer too.

The new buffer shares content with this buffer, which means either buffer's change of content will be visible to the other. The two buffer's position, limit and mark are independent.

Returns:

A duplicated buffer that shares content with this buffer.

equals

public boolean equals(Object other)

Tests whether this long buffer equals to another object.

If other is not a long buffer, then false is returned.

Two long buffers are equals if, and only if, their remaining longs are exactly the same. Position, limit, capacity and mark are not considered.

Overrides:

equals in class Object

Parameters:

other - the object to be compared against

Returns:

Whether this long buffer equals to another object.

See Also:

Object.hashCode()

get

public abstract long get()

Returns the long at the current position and increase the position by 1.

Returns:

The long at the current position.

Throws:

BufferUnderflowException - If the position is equal or greater than limit

get

public LongBuffer get(long[] dest)

Reads longs from the current position into the specified long array and increase the position by the number of longs read.

Calling this method has the same effect as get(dest, 0, dest.length).

Parameters:

dest - The destination long array

Returns:

This buffer

Throws:

BufferUnderflowException - if dest.length is greater than remaining()

get

public LongBuffer get(long[] dest,
                      int off,
                      int len)

Reads longs from the current position into the specified long array, starting from the specified offset, and increase the position by the number of longs read.

Parameters:

dest - The target long array

off - The offset of the long array, must be no less than zero and no greater than dest.length

len - The number of longs to read, must be no less than zero and no greater than dest.length - off

Returns:

This buffer

Throws:

IndexOutOfBoundsException - If either off or len is invalid

BufferUnderflowException - If len is greater than remaining()

get

public abstract long get(int index)

Returns a long at the specified index, and the position is not changed.

Parameters:

index - The index, must be no less than zero and less than limit

Returns:

A long at the specified index.

Throws:

IndexOutOfBoundsException - If index is invalid

hasArray

public final boolean hasArray()

Returns whether this buffer is based on a long array and is read/write.

If this buffer is readonly, then false is returned.

Returns:

Whether this buffer is based on a long array and is read/write.

hashCode

public int hashCode()

Hash code is calculated from the remaining longs.

Position, limit, capacity and mark don't affect the hash code.

Overrides:

hashCode in class Object

Returns:

The hash code calculated from the remaining longs.

See Also:

Object.equals(java.lang.Object)

isDirect

public abstract boolean isDirect()

Returns true if this buffer is direct.

A direct buffer will try its best to take advantage of native memory APIs and it may not stay in java heap, thus not affected by GC.

A long buffer is direct, if it is based on a byte buffer and the byte buffer is direct.

Returns:

True if this buffer is direct.

order

public abstract ByteOrder order()

Returns the byte order used by this buffer when converting longs from/to bytes.

If this buffer is not based on a byte buffer, then always return the platform's native byte order.

Returns:

The byte order used by this buffer when converting longs from/to bytes.

protectedArray

abstract long[] protectedArray()

Child class implements this method to realize array().

Returns:

see array()

protectedArrayOffset

abstract int protectedArrayOffset()

Child class implements this method to realize arrayOffset().

Returns:

see arrayOffset()

protectedHasArray

abstract boolean protectedHasArray()

Child class implements this method to realize hasArray().

Returns:

see hasArray()

put

public abstract LongBuffer put(long l)

Writes the given long to the current position and increase the position by 1.

Parameters:

l - The long to write

Returns:

This buffer

Throws:

BufferOverflowException - If position is equal or greater than limit

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

put

public final LongBuffer put(long[] src)

Writes longs in the given long array to the current position and increase the position by the number of longs written.

Calling this method has the same effect as put(src, 0, src.length).

Parameters:

src - The source long array

Returns:

This buffer

Throws:

BufferOverflowException - If remaining() is less than src.length

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

put

public LongBuffer put(long[] src,
                      int off,
                      int len)

Writes longs in the given long array, starting from the specified offset, to the current position and increase the position by the number of longs written.

Parameters:

src - The source long array

off - The offset of long array, must be no less than zero and no greater than src.length

len - The number of longs to write, must be no less than zero and no greater than src.length - off

Returns:

This buffer

Throws:

BufferOverflowException - If remaining() is less than len

IndexOutOfBoundsException - If either off or len is invalid

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

put

public LongBuffer put(LongBuffer src)

Writes all the remaining longs of the src long buffer to this buffer's current position, and increase both buffers' position by the number of longs copied.

Parameters:

src - The source long buffer

Returns:

This buffer

Throws:

BufferOverflowException - If src.remaining() is greater than this buffer's remaining()

IllegalArgumentException - If src is this buffer

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

put

public abstract LongBuffer put(int index,
                               long l)

Write a long to the specified index of this buffer and the position is not changed.

Parameters:

index - The index, must be no less than zero and less than the limit

l - The long to write

Returns:

This buffer

Throws:

IndexOutOfBoundsException - If index is invalid

ReadOnlyBufferException - If no changes may be made to the contents of this buffer

slice

public abstract LongBuffer slice()

Returns a sliced buffer that shares content with this buffer.

The sliced buffer's capacity will be this buffer's remaining(), and its zero position will correspond to this buffer's current position. The new buffer's position will be 0, limit will be its capacity, and its mark is unset. The new buffer's readonly property and byte order are same as this buffer.

The new buffer shares content with this buffer, which means either buffer's change of content will be visible to the other. The two buffer's position, limit and mark are independent.

Returns:

A sliced buffer that shares content with this buffer.

toString

public String toString()

Returns a string represents the state of this long buffer.

Overrides:

toString in class Object

Returns:

A string represents the state of this long buffer.