DataHeaderFlyweight (Aeron Message Transport)

java.lang.Object
- org.agrona.AbstractMutableDirectBuffer
- - org.agrona.concurrent.UnsafeBuffer
  - - io.aeron.protocol.HeaderFlyweight
    - - io.aeron.protocol.DataHeaderFlyweight

All Implemented Interfaces:

Comparable<DirectBuffer>, AtomicBuffer, DirectBuffer, MutableDirectBuffer
```
public class DataHeaderFlyweight
extends HeaderFlyweight
```
Flyweight for Data Frame header of a message fragment.
Data Frame wiki page.

Field Summary

Fields
Modifier and Type	Field and Description
`static short`	`BEGIN_AND_END_FLAGS` Begin and End Flags.
`static short`	`BEGIN_END_AND_EOS_FLAGS` Begin, End, and EOS Flags.
`static short`	`BEGIN_FLAG` (B) - Fragment that Begins a message Flag.
`static int`	`DATA_OFFSET` Offset in the frame at which the data payload begins.
`static long`	`DEFAULT_RESERVE_VALUE` Default value to be placed in the reserved value field.
`static short`	`END_FLAG` (E) - Fragment that Ends a message Flag.
`static short`	`EOS_FLAG` (S) - End of Stream (EOS) Flag for heartbeats after the publication is closed.
`static int`	`HEADER_LENGTH` Length of the Data Header.
`static int`	`RESERVED_VALUE_OFFSET` Offset in the frame at which the reserved value field begins.
`static int`	`SESSION_ID_FIELD_OFFSET` Offset in the frame at which the session-id field begins.
`static int`	`STREAM_ID_FIELD_OFFSET` Offset in the frame at which the stream-id field begins.
`static int`	`TERM_ID_FIELD_OFFSET` Offset in the frame at which the term-id field begins.
`static int`	`TERM_OFFSET_FIELD_OFFSET` Offset in the frame at which the term-offset field begins.

Fields inherited from class io.aeron.protocol.HeaderFlyweight
CURRENT_VERSION, FLAGS_FIELD_OFFSET, FRAME_LENGTH_FIELD_OFFSET, HDR_TYPE_DATA, HDR_TYPE_ERR, HDR_TYPE_EXT, HDR_TYPE_NAK, HDR_TYPE_PAD, HDR_TYPE_RES, HDR_TYPE_RTTM, HDR_TYPE_SETUP, HDR_TYPE_SM, MIN_HEADER_LENGTH, TYPE_FIELD_OFFSET, VERSION_FIELD_OFFSET

Fields inherited from class org.agrona.concurrent.UnsafeBuffer
ALIGNMENT, DISABLE_BOUNDS_CHECKS_PROP_NAME, SHOULD_BOUNDS_CHECK

Fields inherited from class org.agrona.AbstractMutableDirectBuffer
addressOffset, byteArray, capacity

Fields inherited from interface org.agrona.concurrent.AtomicBuffer
STRICT_ALIGNMENT_CHECKS, STRICT_ALIGNMENT_CHECKS_PROP_NAME

Fields inherited from interface org.agrona.DirectBuffer
DISABLE_ARRAY_CONTENT_PRINTOUT_PROP_NAME, STR_HEADER_LEN

Constructor Summary

Constructors
Constructor and Description
`DataHeaderFlyweight()` Default constructor which can later be used to wrap a frame.
`DataHeaderFlyweight(ByteBuffer buffer)` Construct the flyweight over a frame.
`DataHeaderFlyweight(UnsafeBuffer buffer)` Construct the flyweight over a frame.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static UnsafeBuffer`	`createDefaultHeader(int sessionId, int streamId, int termId)` Return an initialised default Data Frame Header.
`int`	`dataOffset()` Return offset in buffer for data
`static int`	`fragmentLength(UnsafeBuffer termBuffer, int frameOffset)` Get the fragment length field from the header.
`static boolean`	`isEndOfStream(UnsafeBuffer packet)` Does the data frame in the packet have the EOS flag set?
`static boolean`	`isHeartbeat(UnsafeBuffer packet, int length)` Is the frame at data frame at the beginning of packet a heartbeat message?
`long`	`reservedValue()` Get the reserved value in LITTLE_ENDIAN format.
`DataHeaderFlyweight`	`reservedValue(long reservedValue)` Set the reserved value in LITTLE_ENDIAN format.
`static long`	`reservedValue(UnsafeBuffer termBuffer, int frameOffset)` Get the reserved value field from the header.
`int`	`sessionId()` Get the session-id field from the header.
`DataHeaderFlyweight`	`sessionId(int sessionId)` Set the session-id field in the header.
`static int`	`sessionId(UnsafeBuffer termBuffer, int frameOffset)` Get the session-id field from the header.
`int`	`streamId()` Get the stream-id field from the header.
`DataHeaderFlyweight`	`streamId(int streamId)` Set the stream-id field in the header.
`static int`	`streamId(UnsafeBuffer termBuffer, int frameOffset)` Get the stream-id field from the header.
`int`	`termId()` Get the term-id field from the header.
`DataHeaderFlyweight`	`termId(int termId)` Set the term-id field in the header.
`static int`	`termId(UnsafeBuffer termBuffer, int frameOffset)` Get the term-id field from the header.
`int`	`termOffset()` Get the term-offset field from the header.
`DataHeaderFlyweight`	`termOffset(int termOffset)` Set the term-offset field in the header.
`static int`	`termOffset(UnsafeBuffer termBuffer, int frameOffset)` Get the term-offset field from the header.
`String`	`toString()`

Methods inherited from class io.aeron.protocol.HeaderFlyweight
appendFlagsAsChars, flags, flags, flagsToChars, frameLength, frameLength, headerType, headerType, version, version

Methods inherited from class org.agrona.concurrent.UnsafeBuffer
addIntOrdered, addLongOrdered, byteBuffer, compareAndSetInt, compareAndSetLong, ensureCapacity, getAndAddInt, getAndAddLong, getAndSetInt, getAndSetLong, getByteVolatile, getCharVolatile, getIntVolatile, getLongVolatile, getShortVolatile, isExpandable, putByteVolatile, putCharVolatile, putIntOrdered, putIntVolatile, putLongOrdered, putLongVolatile, putShortVolatile, verifyAlignment, wrap, wrap, wrap, wrap, wrap, wrap, wrap, wrapAdjustment

Methods inherited from class org.agrona.AbstractMutableDirectBuffer
addressOffset, boundsCheck, boundsCheck0, byteArray, capacity, checkLimit, compareTo, equals, getByte, getBytes, getBytes, getBytes, getBytes, getBytes, getChar, getChar, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getShort, getShort, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringUtf8, getStringUtf8, getStringUtf8, getStringWithoutLengthAscii, getStringWithoutLengthAscii, getStringWithoutLengthUtf8, hashCode, parseIntAscii, parseLongAscii, parseNaturalIntAscii, parseNaturalLongAscii, putByte, putBytes, putBytes, putBytes, putBytes, putBytes, putChar, putChar, putDouble, putDouble, putFloat, putFloat, putInt, putInt, putIntAscii, putLong, putLong, putLongAscii, putNaturalIntAscii, putNaturalIntAsciiFromEnd, putNaturalLongAscii, putNaturalPaddedIntAscii, putShort, putShort, putStringAscii, putStringAscii, putStringAscii, putStringAscii, putStringUtf8, putStringUtf8, putStringUtf8, putStringUtf8, putStringWithoutLengthAscii, putStringWithoutLengthAscii, putStringWithoutLengthAscii, putStringWithoutLengthAscii, putStringWithoutLengthUtf8, setMemory

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.agrona.DirectBuffer
addressOffset, boundsCheck, byteArray, capacity, checkLimit, getByte, getBytes, getBytes, getBytes, getBytes, getBytes, getChar, getChar, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getShort, getShort, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringAscii, getStringUtf8, getStringUtf8, getStringUtf8, getStringWithoutLengthAscii, getStringWithoutLengthAscii, getStringWithoutLengthUtf8, parseIntAscii, parseLongAscii, parseNaturalIntAscii, parseNaturalLongAscii

Methods inherited from interface java.lang.Comparable
compareTo

- Field Detail
  - HEADER_LENGTH
```
public static final int HEADER_LENGTH
```
    Length of the Data Header.
    
    See Also:
    
    Constant Field Values
  - BEGIN_FLAG
```
public static final short BEGIN_FLAG
```
    (B) - Fragment that Begins a message Flag.
    
    See Also:
    
    Constant Field Values
  - END_FLAG
```
public static final short END_FLAG
```
    (E) - Fragment that Ends a message Flag.
    
    See Also:
    
    Constant Field Values
  - BEGIN_AND_END_FLAGS
```
public static final short BEGIN_AND_END_FLAGS
```
    Begin and End Flags.
    
    See Also:
    
    Constant Field Values
  - EOS_FLAG
```
public static final short EOS_FLAG
```
    (S) - End of Stream (EOS) Flag for heartbeats after the publication is closed.
    
    See Also:
    
    Constant Field Values
  - BEGIN_END_AND_EOS_FLAGS
```
public static final short BEGIN_END_AND_EOS_FLAGS
```
    Begin, End, and EOS Flags.
    
    See Also:
    
    Constant Field Values
  - DEFAULT_RESERVE_VALUE
```
public static final long DEFAULT_RESERVE_VALUE
```
    Default value to be placed in the reserved value field.
    
    See Also:
    
    Constant Field Values
  - TERM_OFFSET_FIELD_OFFSET
```
public static final int TERM_OFFSET_FIELD_OFFSET
```
    Offset in the frame at which the term-offset field begins.
    
    See Also:
    
    Constant Field Values
  - SESSION_ID_FIELD_OFFSET
```
public static final int SESSION_ID_FIELD_OFFSET
```
    Offset in the frame at which the session-id field begins.
    
    See Also:
    
    Constant Field Values
  - STREAM_ID_FIELD_OFFSET
```
public static final int STREAM_ID_FIELD_OFFSET
```
    Offset in the frame at which the stream-id field begins.
    
    See Also:
    
    Constant Field Values
  - TERM_ID_FIELD_OFFSET
```
public static final int TERM_ID_FIELD_OFFSET
```
    Offset in the frame at which the term-id field begins.
    
    See Also:
    
    Constant Field Values
  - RESERVED_VALUE_OFFSET
```
public static final int RESERVED_VALUE_OFFSET
```
    Offset in the frame at which the reserved value field begins.
    
    See Also:
    
    Constant Field Values
  - DATA_OFFSET
```
public static final int DATA_OFFSET
```
    Offset in the frame at which the data payload begins.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - DataHeaderFlyweight
```
public DataHeaderFlyweight()
```
    Default constructor which can later be used to wrap a frame.
  - DataHeaderFlyweight
```
public DataHeaderFlyweight(UnsafeBuffer buffer)
```
    Construct the flyweight over a frame.
    
    Parameters:
    
    buffer - containing the frame.
  - DataHeaderFlyweight
```
public DataHeaderFlyweight(ByteBuffer buffer)
```
    Construct the flyweight over a frame.
    
    Parameters:
    
    buffer - containing the frame.
- Method Detail
  - fragmentLength
```
public static int fragmentLength(UnsafeBuffer termBuffer,
                                 int frameOffset)
```
    Get the fragment length field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the fragment length field from the header.
  - isHeartbeat
```
public static boolean isHeartbeat(UnsafeBuffer packet,
                                  int length)
```
    Is the frame at data frame at the beginning of packet a heartbeat message?
    
    Parameters:
    
    packet - containing the data frame.
    
    length - of the data frame.
    
    Returns:
    
    true if a heartbeat otherwise false.
  - isEndOfStream
```
public static boolean isEndOfStream(UnsafeBuffer packet)
```
    Does the data frame in the packet have the EOS flag set?
    
    Parameters:
    
    packet - containing the data frame.
    
    Returns:
    
    true if the EOS flag is set otherwise false.
  - sessionId
```
public int sessionId()
```
    Get the session-id field from the header.
    
    Returns:
    
    the session-id field from the header.
  - sessionId
```
public static int sessionId(UnsafeBuffer termBuffer,
                            int frameOffset)
```
    Get the session-id field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the session-id field from the header.
  - sessionId
```
public DataHeaderFlyweight sessionId(int sessionId)
```
    Set the session-id field in the header.
    
    Parameters:
    
    sessionId - value to set.
    
    Returns:
    
    this for a fluent API.
  - streamId
```
public int streamId()
```
    Get the stream-id field from the header.
    
    Returns:
    
    the stream-id field from the header.
  - streamId
```
public static int streamId(UnsafeBuffer termBuffer,
                           int frameOffset)
```
    Get the stream-id field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the stream-id field from the header.
  - streamId
```
public DataHeaderFlyweight streamId(int streamId)
```
    Set the stream-id field in the header.
    
    Parameters:
    
    streamId - value to set.
    
    Returns:
    
    this for a fluent API.
  - termId
```
public int termId()
```
    Get the term-id field from the header.
    
    Returns:
    
    the term-id field from the header.
  - termId
```
public static int termId(UnsafeBuffer termBuffer,
                         int frameOffset)
```
    Get the term-id field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the term-id field from the header.
  - termId
```
public DataHeaderFlyweight termId(int termId)
```
    Set the term-id field in the header.
    
    Parameters:
    
    termId - value to set.
    
    Returns:
    
    this for a fluent API.
  - termOffset
```
public int termOffset()
```
    Get the term-offset field from the header.
    
    Returns:
    
    the term-offset field from the header.
  - termOffset
```
public static int termOffset(UnsafeBuffer termBuffer,
                             int frameOffset)
```
    Get the term-offset field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the term-offset field from the header.
  - termOffset
```
public DataHeaderFlyweight termOffset(int termOffset)
```
    Set the term-offset field in the header.
    
    Parameters:
    
    termOffset - value to set.
    
    Returns:
    
    this for a fluent API.
  - reservedValue
```
public long reservedValue()
```
    Get the reserved value in LITTLE_ENDIAN format.
    
    Returns:
    
    value of the reserved value.
  - reservedValue
```
public static long reservedValue(UnsafeBuffer termBuffer,
                                 int frameOffset)
```
    Get the reserved value field from the header.
    
    Parameters:
    
    termBuffer - containing the header.
    
    frameOffset - in the buffer where the header starts.
    
    Returns:
    
    the reserved value field from the header.
  - reservedValue
```
public DataHeaderFlyweight reservedValue(long reservedValue)
```
    Set the reserved value in LITTLE_ENDIAN format.
    
    Parameters:
    
    reservedValue - to be stored
    
    Returns:
    
    flyweight
  - dataOffset
```
public int dataOffset()
```
    Return offset in buffer for data
    
    Returns:
    
    offset of data in the buffer
  - createDefaultHeader
```
public static UnsafeBuffer createDefaultHeader(int sessionId,
                                               int streamId,
                                               int termId)
```
    Return an initialised default Data Frame Header.
    
    Parameters:
    
    sessionId - for the header
    
    streamId - for the header
    
    termId - for the header
    
    Returns:
    
    byte array containing the header
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class UnsafeBuffer

Class DataHeaderFlyweight

Field Summary

Fields inherited from class io.aeron.protocol.HeaderFlyweight

Fields inherited from class org.agrona.concurrent.UnsafeBuffer

Fields inherited from class org.agrona.AbstractMutableDirectBuffer

Fields inherited from interface org.agrona.concurrent.AtomicBuffer

Fields inherited from interface org.agrona.DirectBuffer

Constructor Summary

Method Summary

Methods inherited from class io.aeron.protocol.HeaderFlyweight

Methods inherited from class org.agrona.concurrent.UnsafeBuffer

Methods inherited from class org.agrona.AbstractMutableDirectBuffer

Methods inherited from class java.lang.Object

Methods inherited from interface org.agrona.MutableDirectBuffer

Methods inherited from interface org.agrona.DirectBuffer

Methods inherited from interface java.lang.Comparable

Field Detail

HEADER_LENGTH

BEGIN_FLAG

END_FLAG

BEGIN_AND_END_FLAGS

EOS_FLAG

BEGIN_END_AND_EOS_FLAGS

DEFAULT_RESERVE_VALUE

TERM_OFFSET_FIELD_OFFSET

SESSION_ID_FIELD_OFFSET

STREAM_ID_FIELD_OFFSET

TERM_ID_FIELD_OFFSET

RESERVED_VALUE_OFFSET

DATA_OFFSET

Constructor Detail

DataHeaderFlyweight

DataHeaderFlyweight

DataHeaderFlyweight

Method Detail

fragmentLength

isHeartbeat

isEndOfStream

sessionId

sessionId

sessionId

streamId

streamId

streamId

termId

termId

termId

termOffset

termOffset

termOffset

reservedValue

reservedValue

reservedValue

dataOffset

createDefaultHeader

toString