io.aeron.logbuffer

Class BufferClaim

java.lang.Object

io.aeron.logbuffer.BufferClaim

Direct Known Subclasses:

ExclusiveBufferClaim

public class BufferClaim
extends java.lang.Object

Represents a claimed range in a buffer to be used for recording a message without copy semantics for later commit.

The claimed space is in buffer() between offset() and offset() + length(). When the buffer is filled with message data, use commit() to make it available to subscribers.

If the claimed space is no longer required it can be aborted by calling abort().

See Also:

Publication.tryClaim(int, BufferClaim)

Field Summary

Fields

Modifier and Type	Field and Description
protected org.agrona.concurrent.UnsafeBuffer	buffer

Constructor Summary

Constructors

Constructor and Description
BufferClaim()

Method Summary

Modifier and Type	Method and Description
void	abort() Abort a claim of the message space to the log buffer so that the log can progress by ignoring this claim.
org.agrona.MutableDirectBuffer	buffer() The referenced buffer to be used.
void	commit() Commit the message to the log buffer so that is it available to subscribers.
byte	flags() Get the value of the flags field.
BufferClaim	flags(byte flags) Set the value of the header flags field.
int	headerType() Get the value of the header type field.
BufferClaim	headerType(int type) Set the value of the header type field.
int	length() The length of the claimed range in the buffer.
int	offset() The offset in the buffer at which the claimed range begins.
BufferClaim	putBytes(org.agrona.DirectBuffer srcBuffer, int srcIndex, int length) Put bytes into the claimed buffer space for a message.
long	reservedValue() Get the value stored in the reserve space at the end of a data frame header.
BufferClaim	reservedValue(long value) Write the provided value into the reserved space at the end of the data frame header.
void	wrap(org.agrona.concurrent.AtomicBuffer buffer, int offset, int length) Wrap a region of an underlying log buffer so can can represent a claimed space for use by a publisher.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

buffer

protected final org.agrona.concurrent.UnsafeBuffer buffer

Constructor Detail

BufferClaim

public BufferClaim()

Method Detail

wrap

public final void wrap(org.agrona.concurrent.AtomicBuffer buffer,
                       int offset,
                       int length)

Wrap a region of an underlying log buffer so can can represent a claimed space for use by a publisher.

Parameters:

buffer - to be wrapped.

offset - at which the claimed region begins including space for the header.

length - length of the underlying claimed region including space for the header.

buffer

public final org.agrona.MutableDirectBuffer buffer()

The referenced buffer to be used.

Returns:

the referenced buffer to be used..

offset

public final int offset()

The offset in the buffer at which the claimed range begins.

Returns:

offset in the buffer at which the range begins.

length

public final int length()

The length of the claimed range in the buffer.

Returns:

length of the range in the buffer.

headerType

public final int headerType()

Get the value of the header type field. The lower 16 bits are valid.

Returns:

the value of the header type field.

See Also:

DataHeaderFlyweight

flags

public final byte flags()

Get the value of the flags field.

Returns:

the value of the header flags field.

See Also:

DataHeaderFlyweight

flags

public BufferClaim flags(byte flags)

Set the value of the header flags field.

Parameters:

flags - value to be set in the header.

Returns:

this for a fluent API.

See Also:

DataHeaderFlyweight

headerType

public BufferClaim headerType(int type)

Set the value of the header type field. The lower 16 bits are valid.

Parameters:

type - value to be set in the header.

Returns:

this for a fluent API.

See Also:

DataHeaderFlyweight

reservedValue

public final long reservedValue()

Get the value stored in the reserve space at the end of a data frame header.

Note: The value is in ByteOrder.LITTLE_ENDIAN format.

Returns:

the value stored in the reserve space at the end of a data frame header.

See Also:

DataHeaderFlyweight

reservedValue

public BufferClaim reservedValue(long value)

Write the provided value into the reserved space at the end of the data frame header.

Note: The value will be written in ByteOrder.LITTLE_ENDIAN format.

Parameters:

value - to be stored in the reserve space at the end of a data frame header.

Returns:

this for fluent API semantics.

See Also:

DataHeaderFlyweight

putBytes

public final BufferClaim putBytes(org.agrona.DirectBuffer srcBuffer,
                                  int srcIndex,
                                  int length)

Put bytes into the claimed buffer space for a message. To write multiple parts then use buffer() and offset().

Parameters:

srcBuffer - to copy into the claimed space.

srcIndex - in the source buffer from which to copy.

length - of the source buffer to copy.

Returns:

this for a fluent API.

commit

public final void commit()

Commit the message to the log buffer so that is it available to subscribers.

abort

public final void abort()

Abort a claim of the message space to the log buffer so that the log can progress by ignoring this claim.