public interface ByteBuf
An interface wrapper around a java.nio.ByteBuffer
which additionally is Closeable
, so that pooled byte buffers know
how.
This interface is not frozen yet, and methods may be added in a minor release, so beware implementing this yourself.
Modifier and Type | Method and Description |
---|---|
byte[] |
array()
Returns the byte array that backs this buffer (optional operation).
|
java.nio.ByteBuffer |
asNIO()
Gets the underlying NIO
ByteBuffer . |
ByteBuf |
asReadOnly()
Creates a new, read-only byte buffer that shares this buffer's content.
|
int |
capacity()
Returns this buffer's capacity.
|
ByteBuf |
clear()
Clears this buffer.
|
ByteBuf |
duplicate()
Creates a new byte buffer that shares this buffer's content.
|
ByteBuf |
flip()
Flips this buffer.
|
byte |
get()
Relative get method.
|
ByteBuf |
get(byte[] bytes)
Relative bulk
get method. |
ByteBuf |
get(byte[] bytes,
int offset,
int length)
Relative bulk get method.
|
byte |
get(int index)
Absolute get method.
|
ByteBuf |
get(int index,
byte[] bytes)
Absolute bulk
get method. |
ByteBuf |
get(int index,
byte[] bytes,
int offset,
int length)
Absolute bulk get method.
|
double |
getDouble()
Relative get method for reading a double value.
|
double |
getDouble(int index)
Absolute get method for reading a double value.
|
int |
getInt()
Relative get method for reading an int value.
|
int |
getInt(int index)
Absolute get method for reading an int value.
|
long |
getLong()
Relative get method for reading a long value.
|
long |
getLong(int index)
Absolute get method for reading a long value.
|
int |
getReferenceCount()
Gets the current reference count, which starts at 0.
|
boolean |
hasRemaining()
States whether there are any elements between the current position and the limit.
|
int |
limit()
Returns this buffer's limit.
|
ByteBuf |
limit(int newLimit)
Sets this buffer's limit.
|
ByteBuf |
order(java.nio.ByteOrder byteOrder)
Modifies this buffer's byte order.
|
int |
position()
Returns this buffer's position.
|
ByteBuf |
position(int newPosition)
Sets this buffer's position.
|
ByteBuf |
put(byte b)
Relative put method (optional operation).
|
ByteBuf |
put(byte[] src,
int offset,
int length)
Relative bulk put method (optional operation).
|
ByteBuf |
put(int index,
byte b)
Absolute put method (optional operation).
|
void |
release()
Release a reference to this object.
|
int |
remaining()
Returns the number of elements between the current position and the limit.
|
ByteBuf |
retain()
Retain an additional reference to this object.
|
int capacity()
ByteBuf put(int index, byte b)
Absolute put method (optional operation).
Writes the given byte into this buffer at the given index.
index
- The index at which the byte will be writtenb
- The byte value to be writtenjava.lang.IndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limitjava.nio.ReadOnlyBufferException
- If this buffer is read-onlyint remaining()
ByteBuf put(byte[] src, int offset, int length)
Relative bulk put method (optional operation).
This method transfers bytes into this buffer from the given source array. If there are more bytes to be copied from the array
than remain in this buffer, that is, if length > remaining()
, then no bytes are transferred and a BufferOverflowException
is thrown.
Otherwise, this method copies length
bytes from the given array into this buffer, starting at the given offset in the
array and at the current position of this buffer. The position of this buffer is then incremented by length
.
In other words, an invocation of this method of the form dst.put(src, off, len)
has exactly the same effect as the
loop
for (int i = off; i < off + len; i++) {
dst.put(a[i]);
}
except that it first checks that there is sufficient space in this buffer and it is potentially much more efficient.
src
- The array from which bytes are to be readoffset
- The offset within the array of the first byte to be read; must be non-negative and no larger than array.length
length
- The number of bytes to be read from the given array; must be non-negative and no larger than array.length -
offset
java.nio.BufferOverflowException
- If there is insufficient space in this bufferjava.lang.IndexOutOfBoundsException
- If the preconditions on the offset
and length
parameters do not holdjava.nio.ReadOnlyBufferException
- If this buffer is read-onlyboolean hasRemaining()
true
if, and only if, there is at least one element remaining in this bufferByteBuf put(byte b)
Relative put method (optional operation).
Writes the given byte into this buffer at the current position, and then increments the position.
b
- The byte to be writtenjava.nio.BufferOverflowException
- If this buffer's current position is not smaller than its limitjava.nio.ReadOnlyBufferException
- If this buffer is read-onlyByteBuf flip()
Flips this buffer. The limit is set to the current position and then the position is set to zero. If the mark is defined then it is discarded.
After a sequence of channel-read or put operations, invoke this method to prepare for a sequence of channel-write or relative get operations. For example:
buf.put(magic); // Prepend header in.read(buf); // Read data into rest of buffer buf.flip(); // Flip buffer out.write(buf); // Write header + data to channel
This method is often used in conjunction with the compact
method when transferring data from
one place to another.
byte[] array()
Returns the byte array that backs this buffer (optional operation).
Modifications to this buffer's content will cause the returned array's content to be modified, and vice versa.
java.nio.ReadOnlyBufferException
- If this buffer is backed by an array but is read-onlyjava.lang.UnsupportedOperationException
- If this buffer is not backed by an accessible arrayint limit()
ByteBuf position(int newPosition)
newPosition
- The new position value; must be non-negative and no larger than the current limitjava.lang.IllegalArgumentException
- If the preconditions on newPosition
do not holdByteBuf clear()
Clears this buffer. The position is set to zero, the limit is set to the capacity, and the mark is discarded.
Invoke this method before using a sequence of channel-read or put operations to fill this buffer. For example:
buf.clear(); // Prepare buffer for reading in.read(buf); // Read data
This method does not actually erase the data in the buffer, but it is named as if it did because it will most often be used in situations in which that might as well be the case.
ByteBuf order(java.nio.ByteOrder byteOrder)
byteOrder
- The new byte order, either BIG_ENDIAN
or LITTLE_ENDIAN
byte get()
java.nio.BufferUnderflowException
- If the buffer's current position is not smaller than its limitbyte get(int index)
index
- The index from which the byte will be readjava.lang.IndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limitByteBuf get(byte[] bytes)
Relative bulk get
method.
This method transfers bytes from this buffer into the given destination array. An invocation of this method of the form src.get(a)
behaves in exactly the same way as the invocation:
src.get(a, 0, a.length)
bytes
- the destination byte arrayjava.nio.BufferUnderflowException
- If there are fewer than length
bytes remaining in this bufferByteBuf get(int index, byte[] bytes)
Absolute bulk get
method.
This method transfers bytes from this buffer into the given destination array. An invocation of this method of the form src.get(a)
behaves in exactly the same way as the invocation:
src.get(index, a, 0, a.length)
index
- The index from which the bytes will be readbytes
- the destination byte arrayjava.nio.BufferUnderflowException
- If there are fewer than length
bytes remaining in this bufferByteBuf get(byte[] bytes, int offset, int length)
This method transfers bytes from this buffer into the given
destination array. If there are fewer bytes remaining in the
buffer than are required to satisfy the request, that is, if
length > remaining(), then no
bytes are transferred and a BufferUnderflowException
is
thrown.
Otherwise, this method copies length bytes from this buffer into the given array, starting at the current position of this buffer and at the given offset in the array. The position of this buffer is then incremented by length.
In other words, an invocation of this method of the form src.get(dst, off, len) has exactly the same effect as the loop
for (int i = off; i < off + len; i++)
dst[i] = src.get();
except that it first checks that there are sufficient bytes in
this buffer and it is potentially much more efficient.bytes
- The array into which bytes are to be writtenoffset
- The offset within the array of the first byte to be
written; must be non-negative and no larger than
dst.lengthlength
- The maximum number of bytes to be written to the given
array; must be non-negative and no larger than
dst.length - offsetjava.nio.BufferUnderflowException
- If there are fewer than length bytes
remaining in this bufferjava.lang.IndexOutOfBoundsException
- If the preconditions on the offset and length
parameters do not holdByteBuf get(int index, byte[] bytes, int offset, int length)
This method transfers bytes from this buffer into the given destination array. If there are fewer bytes remaining in the buffer
than are required to satisfy the request, that is, if length > remaining
, then no bytes are
transferred and a BufferUnderflowException
is thrown.
Otherwise, this method copies length
bytes from this buffer into the given array, starting at the given index buffer
and at the given offset in the array.
In other words, an invocation of this method of the form src.get(dst, off, len)
has exactly the same
effect as the loop
for (int i = off; i < off + len; i++)
dst[i] = src.get(i);
except that it first checks that there are sufficient bytes in this buffer and it is potentially much more efficient.index
- The index from which the bytes will be readbytes
- The array into which bytes are to be writtenoffset
- The offset within the array of the first byte 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
java.nio.BufferUnderflowException
- If there are fewer than length
bytes remaining in this bufferjava.lang.IndexOutOfBoundsException
- If the preconditions on the offset
and length
parameters do not holdlong getLong()
Relative get method for reading a long value.
Reads the next eight bytes at this buffer's current position, composing them into a long value according to the current byte order, and then increments the position by eight.
java.nio.BufferUnderflowException
- If there are fewer than eight bytes remaining in this bufferlong getLong(int index)
Reads eight bytes at the given index, composing them into a long value according to the current byte order.
index
- The index from which the bytes will be readjava.lang.IndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limit, minus sevendouble getDouble()
Relative get method for reading a double value.
Reads the next eight bytes at this buffer's current position, composing them into a double value according to the current byte order, and then increments the position by eight.
java.nio.BufferUnderflowException
- If there are fewer than eight bytes remaining in this bufferdouble getDouble(int index)
Reads eight bytes at the given index, composing them into a double value according to the current byte order.
index
- The index from which the bytes will be readjava.lang.IndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limit, minus sevenint getInt()
Relative get method for reading an int value.
Reads the next four bytes at this buffer's current position, composing them into an int value according to the current byte order, and then increments the position by four.
java.nio.BufferUnderflowException
- If there are fewer than four bytes remaining in this bufferint getInt(int index)
Reads four bytes at the given index, composing them into a int value according to the current byte order.
index
- The index from which the bytes will be readjava.lang.IndexOutOfBoundsException
- If index
is negative or not smaller than the buffer's limit, minus threeint position()
ByteBuf limit(int newLimit)
newLimit
- The new limit value; must be non-negative and no larger than this buffer's capacityjava.lang.IllegalArgumentException
- If the preconditions on newLimit
do not holdByteBuf asReadOnly()
Creates a new, read-only byte buffer that shares this buffer's content.
The content of the new buffer will be that of this buffer. Changes to this buffer's content will be visible in the new buffer; the new buffer itself, however, will be read-only and will not allow the shared content to be modified. The two buffers' position, limit, and mark values will be independent.
The new buffer's capacity, limit, position, and mark values will be identical to those of this buffer.
ByteBuf duplicate()
Creates a new byte buffer that shares this buffer's content.
The content of the new buffer will be that of this buffer. Changes to this buffer's content will be visible in the new buffer, and vice versa; the two buffers' position, limit, and mark values will be independent.
The new buffer's capacity, limit, position, and mark values will be identical to those of this buffer. The new buffer will be direct if, and only if, this buffer is direct, and it will be read-only if, and only if, this buffer is read-only.
java.nio.ByteBuffer asNIO()
ByteBuffer
. Changes made directly to the returned buffer will be reflected in this instance, and
vice versa, so be careful. This method should really only be used so that the underlying buffer can be passed directly to a socket
channel.int getReferenceCount()
ByteBuf retain()
void release()
java.lang.IllegalStateException
- if the reference count is already 0Copyright © 2010 - 2020 Adobe. All Rights Reserved