public class EmptyChannelBuffer extends BigEndianHeapChannelBuffer
ChannelBuffers.EMPTY_BUFFER and returned by ChannelBuffers.buffer(int) etc when
an empty buffer is requested.
Note: For backwards compatibility, this class extends BigEndianHeapChannelBuffer.
However, it never makes any writes to the reader and writer indices, which avoids contention
when the singleton instance is used concurrently.
| Modifier and Type | Field and Description |
|---|---|
private static byte[] |
BUFFER |
array| Constructor and Description |
|---|
EmptyChannelBuffer() |
| Modifier and Type | Method and Description |
|---|---|
protected void |
checkReadableBytes(int length)
Throws an
IndexOutOfBoundsException the length is not 0. |
private void |
checkWritableBytes(int length)
Throws an
IndexOutOfBoundsException the length is not 0. |
void |
clear()
Sets the
readerIndex and writerIndex of this buffer to
0. |
void |
discardReadBytes()
Discards the bytes between the 0th index and
readerIndex. |
void |
markReaderIndex()
Marks the current
readerIndex in this buffer. |
void |
markWriterIndex()
Marks the current
writerIndex in this buffer. |
void |
readBytes(byte[] dst)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex and increases the readerIndex
by the number of the transferred bytes (= dst.length). |
void |
readBytes(byte[] dst,
int dstIndex,
int length)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex and increases the readerIndex
by the number of the transferred bytes (= length). |
void |
readBytes(java.nio.ByteBuffer dst)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex until the destination's position
reaches its limit, and increases the readerIndex by the
number of the transferred bytes. |
void |
readBytes(ChannelBuffer dst)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex until the destination becomes
non-writable, and increases the readerIndex by the number of the
transferred bytes. |
void |
readBytes(ChannelBuffer dst,
int length)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex and increases the readerIndex
by the number of the transferred bytes (= length). |
void |
readBytes(ChannelBuffer dst,
int dstIndex,
int length)
Transfers this buffer's data to the specified destination starting at
the current
readerIndex and increases the readerIndex
by the number of the transferred bytes (= length). |
int |
readBytes(java.nio.channels.GatheringByteChannel out,
int length)
Transfers this buffer's data to the specified stream starting at the
current
readerIndex. |
ChannelBuffer |
readBytes(int length)
Transfers this buffer's data to a newly created buffer starting at
the current
readerIndex and increases the readerIndex
by the number of the transferred bytes (= length). |
void |
readBytes(java.io.OutputStream out,
int length)
Transfers this buffer's data to the specified stream starting at the
current
readerIndex. |
void |
readerIndex(int readerIndex)
Sets the
readerIndex of this buffer. |
ChannelBuffer |
readSlice(int length)
Returns a new slice of this buffer's sub-region starting at the current
readerIndex and increases the readerIndex by the size
of the new slice (= length). |
void |
resetReaderIndex()
Repositions the current
readerIndex to the marked
readerIndex in this buffer. |
void |
resetWriterIndex()
Repositions the current
writerIndex to the marked
writerIndex in this buffer. |
void |
setIndex(int readerIndex,
int writerIndex)
Sets the
readerIndex and writerIndex of this buffer
in one shot. |
void |
skipBytes(int length)
Increases the current
readerIndex by the specified
length in this buffer. |
void |
writeBytes(byte[] src,
int srcIndex,
int length)
Transfers the specified source array's data to this buffer starting at
the current
writerIndex and increases the writerIndex
by the number of the transferred bytes (= length). |
void |
writeBytes(java.nio.ByteBuffer src)
Transfers the specified source buffer's data to this buffer starting at
the current
writerIndex until the source buffer's position
reaches its limit, and increases the writerIndex by the
number of the transferred bytes. |
void |
writeBytes(ChannelBuffer src,
int length)
Transfers the specified source buffer's data to this buffer starting at
the current
writerIndex and increases the writerIndex
by the number of the transferred bytes (= length). |
void |
writeBytes(ChannelBuffer src,
int srcIndex,
int length)
Transfers the specified source buffer's data to this buffer starting at
the current
writerIndex and increases the writerIndex
by the number of the transferred bytes (= length). |
int |
writeBytes(java.io.InputStream in,
int length)
Transfers the content of the specified stream to this buffer
starting at the current
writerIndex and increases the
writerIndex by the number of the transferred bytes. |
int |
writeBytes(java.nio.channels.ScatteringByteChannel in,
int length)
Transfers the content of the specified channel to this buffer
starting at the current
writerIndex and increases the
writerIndex by the number of the transferred bytes. |
void |
writerIndex(int writerIndex)
Sets the
writerIndex of this buffer. |
void |
writeZero(int length)
Fills this buffer with NUL (0x00) starting at the current
writerIndex and increases the writerIndex by the
specified length. |
copy, duplicate, factory, getInt, getLong, getShort, getUnsignedMedium, order, setInt, setLong, setMedium, setShortarray, arrayOffset, capacity, getByte, getBytes, getBytes, getBytes, getBytes, getBytes, hasArray, isDirect, setByte, setBytes, setBytes, setBytes, setBytes, setBytes, slice, toByteBufferbytesBefore, bytesBefore, bytesBefore, bytesBefore, bytesBefore, bytesBefore, compareTo, copy, ensureWritableBytes, equals, getBytes, getBytes, getBytes, getChar, getDouble, getFloat, getMedium, getUnsignedByte, getUnsignedInt, getUnsignedShort, hashCode, indexOf, indexOf, readable, readableBytes, readByte, readChar, readDouble, readerIndex, readFloat, readInt, readLong, readMedium, readShort, readUnsignedByte, readUnsignedInt, readUnsignedMedium, readUnsignedShort, setBytes, setBytes, setBytes, setChar, setDouble, setFloat, setZero, slice, toByteBuffer, toByteBuffers, toByteBuffers, toString, toString, toString, writable, writableBytes, writeByte, writeBytes, writeBytes, writeChar, writeDouble, writeFloat, writeInt, writeLong, writeMedium, writerIndex, writeShortpublic void clear()
ChannelBufferreaderIndex and writerIndex of this buffer to
0.
This method is identical to setIndex(0, 0).
Please note that the behavior of this method is different
from that of NIO buffer, which sets the limit to
the capacity of the buffer.
clear in interface ChannelBufferclear in class AbstractChannelBufferpublic void readerIndex(int readerIndex)
ChannelBufferreaderIndex of this buffer.readerIndex in interface ChannelBufferreaderIndex in class AbstractChannelBufferpublic void writerIndex(int writerIndex)
ChannelBufferwriterIndex of this buffer.writerIndex in interface ChannelBufferwriterIndex in class AbstractChannelBufferpublic void setIndex(int readerIndex,
int writerIndex)
ChannelBufferreaderIndex and writerIndex of this buffer
in one shot. This method is useful when you have to worry about the
invocation order of ChannelBuffer.readerIndex(int) and ChannelBuffer.writerIndex(int)
methods. For example, the following code will fail:
// Create a buffer whose readerIndex, writerIndex and capacity are // 0, 0 and 8 respectively.The following code will also fail:ChannelBufferbuf =ChannelBuffers.buffer(8); // IndexOutOfBoundsException is thrown because the specified // readerIndex (2) cannot be greater than the current writerIndex (0). buf.readerIndex(2); buf.writerIndex(4);
// Create a buffer whose readerIndex, writerIndex and capacity are // 0, 8 and 8 respectively.By contrast, this method guarantees that it never throws anChannelBufferbuf =ChannelBuffers.wrappedBuffer(new byte[8]); // readerIndex becomes 8. buf.readLong(); // IndexOutOfBoundsException is thrown because the specified // writerIndex (4) cannot be less than the current readerIndex (8). buf.writerIndex(4); buf.readerIndex(2);
IndexOutOfBoundsException as long as the specified
indexes meet basic constraints, regardless what the current index
values of the buffer are:
// No matter what the current state of the buffer is, the following // call always succeeds as long as the capacity of the buffer is not // less than 4. buf.setIndex(2, 4);
setIndex in interface ChannelBuffersetIndex in class AbstractChannelBufferpublic void markReaderIndex()
ChannelBufferreaderIndex in this buffer. You can
reposition the current readerIndex to the marked
readerIndex by calling ChannelBuffer.resetReaderIndex().
The initial value of the marked readerIndex is 0.markReaderIndex in interface ChannelBuffermarkReaderIndex in class AbstractChannelBufferpublic void resetReaderIndex()
ChannelBufferreaderIndex to the marked
readerIndex in this buffer.resetReaderIndex in interface ChannelBufferresetReaderIndex in class AbstractChannelBufferpublic void markWriterIndex()
ChannelBufferwriterIndex in this buffer. You can
reposition the current writerIndex to the marked
writerIndex by calling ChannelBuffer.resetWriterIndex().
The initial value of the marked writerIndex is 0.markWriterIndex in interface ChannelBuffermarkWriterIndex in class AbstractChannelBufferpublic void resetWriterIndex()
ChannelBufferwriterIndex to the marked
writerIndex in this buffer.resetWriterIndex in interface ChannelBufferresetWriterIndex in class AbstractChannelBufferpublic void discardReadBytes()
ChannelBufferreaderIndex.
It moves the bytes between readerIndex and writerIndex
to the 0th index, and sets readerIndex and writerIndex
to 0 and oldWriterIndex - oldReaderIndex respectively.
Please refer to the class documentation for more detailed explanation.
discardReadBytes in interface ChannelBufferdiscardReadBytes in class AbstractChannelBufferpublic ChannelBuffer readBytes(int length)
ChannelBufferreaderIndex and increases the readerIndex
by the number of the transferred bytes (= length).
The returned buffer's readerIndex and writerIndex are
0 and length respectively.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferlength - the number of bytes to transferpublic ChannelBuffer readSlice(int length)
ChannelBufferreaderIndex and increases the readerIndex by the size
of the new slice (= length).readSlice in interface ChannelBufferreadSlice in class AbstractChannelBufferlength - the size of the new slicepublic void readBytes(byte[] dst,
int dstIndex,
int length)
ChannelBufferreaderIndex and increases the readerIndex
by the number of the transferred bytes (= length).readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferdstIndex - the first index of the destinationlength - the number of bytes to transferpublic void readBytes(byte[] dst)
ChannelBufferreaderIndex and increases the readerIndex
by the number of the transferred bytes (= dst.length).readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferpublic void readBytes(ChannelBuffer dst)
ChannelBufferreaderIndex until the destination becomes
non-writable, and increases the readerIndex by the number of the
transferred bytes. This method is basically same with
ChannelBuffer.readBytes(ChannelBuffer, int, int), except that this method
increases the writerIndex of the destination by the number of
the transferred bytes while ChannelBuffer.readBytes(ChannelBuffer, int, int)
does not.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferpublic void readBytes(ChannelBuffer dst, int length)
ChannelBufferreaderIndex and increases the readerIndex
by the number of the transferred bytes (= length). This method
is basically same with ChannelBuffer.readBytes(ChannelBuffer, int, int),
except that this method increases the writerIndex of the
destination by the number of the transferred bytes (= length)
while ChannelBuffer.readBytes(ChannelBuffer, int, int) does not.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferpublic void readBytes(ChannelBuffer dst, int dstIndex, int length)
ChannelBufferreaderIndex and increases the readerIndex
by the number of the transferred bytes (= length).readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferdstIndex - the first index of the destinationlength - the number of bytes to transferpublic void readBytes(java.nio.ByteBuffer dst)
ChannelBufferreaderIndex until the destination's position
reaches its limit, and increases the readerIndex by the
number of the transferred bytes.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferpublic int readBytes(java.nio.channels.GatheringByteChannel out,
int length)
throws java.io.IOException
ChannelBufferreaderIndex.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferlength - the maximum number of bytes to transferjava.io.IOException - if the specified channel threw an exception during I/Opublic void readBytes(java.io.OutputStream out,
int length)
throws java.io.IOException
ChannelBufferreaderIndex.readBytes in interface ChannelBufferreadBytes in class AbstractChannelBufferlength - the number of bytes to transferjava.io.IOException - if the specified stream threw an exception during I/Opublic void skipBytes(int length)
ChannelBufferreaderIndex by the specified
length in this buffer.skipBytes in interface ChannelBufferskipBytes in class AbstractChannelBufferpublic void writeBytes(byte[] src,
int srcIndex,
int length)
ChannelBufferwriterIndex and increases the writerIndex
by the number of the transferred bytes (= length).writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBuffersrcIndex - the first index of the sourcelength - the number of bytes to transferpublic void writeBytes(ChannelBuffer src, int length)
ChannelBufferwriterIndex and increases the writerIndex
by the number of the transferred bytes (= length). This method
is basically same with ChannelBuffer.writeBytes(ChannelBuffer, int, int),
except that this method increases the readerIndex of the source
buffer by the number of the transferred bytes (= length) while
ChannelBuffer.writeBytes(ChannelBuffer, int, int) does not.writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBufferlength - the number of bytes to transferpublic void writeBytes(ChannelBuffer src, int srcIndex, int length)
ChannelBufferwriterIndex and increases the writerIndex
by the number of the transferred bytes (= length).writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBuffersrcIndex - the first index of the sourcelength - the number of bytes to transferpublic void writeBytes(java.nio.ByteBuffer src)
ChannelBufferwriterIndex until the source buffer's position
reaches its limit, and increases the writerIndex by the
number of the transferred bytes.writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBufferpublic int writeBytes(java.io.InputStream in,
int length)
throws java.io.IOException
ChannelBufferwriterIndex and increases the
writerIndex by the number of the transferred bytes.writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBufferlength - the number of bytes to transferjava.io.IOException - if the specified stream threw an exception during I/Opublic int writeBytes(java.nio.channels.ScatteringByteChannel in,
int length)
throws java.io.IOException
ChannelBufferwriterIndex and increases the
writerIndex by the number of the transferred bytes.writeBytes in interface ChannelBufferwriteBytes in class AbstractChannelBufferlength - the maximum number of bytes to transferjava.io.IOException - if the specified channel threw an exception during I/Opublic void writeZero(int length)
ChannelBufferwriterIndex and increases the writerIndex by the
specified length.writeZero in interface ChannelBufferwriteZero in class AbstractChannelBufferlength - the number of NULs to write to the bufferprivate void checkWritableBytes(int length)
IndexOutOfBoundsException the length is not 0.protected void checkReadableBytes(int length)
IndexOutOfBoundsException the length is not 0.checkReadableBytes in class AbstractChannelBuffer