io.aeron.protocol.HeaderFlyweight Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of aeron-client Show documentation
Show all versions of aeron-client Show documentation
Efficient reliable UDP unicast, UDP multicast, and IPC transport protocol.
/*
* Copyright 2014-2021 Real Logic Limited.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.aeron.protocol;
import org.agrona.LangUtil;
import org.agrona.concurrent.UnsafeBuffer;
import java.io.IOException;
import java.nio.ByteBuffer;
import static java.nio.ByteOrder.LITTLE_ENDIAN;
import static org.agrona.BitUtil.SIZE_OF_SHORT;
/**
* Flyweight for general Aeron network protocol header of a message frame.
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Frame Length |
* +---------------------------------------------------------------+
* | Version | Flags | Type |
* +-------------+---------------+---------------------------------+
* | Depends on Type ...
*
*/
public class HeaderFlyweight extends UnsafeBuffer
{
/**
* header type PAD
*/
public static final int HDR_TYPE_PAD = 0x00;
/**
* header type DATA
*/
public static final int HDR_TYPE_DATA = 0x01;
/**
* header type NAK
*/
public static final int HDR_TYPE_NAK = 0x02;
/**
* header type SM
*/
public static final int HDR_TYPE_SM = 0x03;
/**
* header type ERR
*/
public static final int HDR_TYPE_ERR = 0x04;
/**
* header type SETUP
*/
public static final int HDR_TYPE_SETUP = 0x05;
/**
* header type RTT Measurement
*/
public static final int HDR_TYPE_RTTM = 0x06;
/**
* header type RESOLUTION
*/
public static final int HDR_TYPE_RES = 0x07;
/**
* header type EXT
*/
public static final int HDR_TYPE_EXT = 0xFFFF;
/**
* default version
*/
public static final byte CURRENT_VERSION = 0x0;
/**
* Offset in the frame at which the frame length field begins.
*/
public static final int FRAME_LENGTH_FIELD_OFFSET = 0;
/**
* Offset in the frame at which the version field begins.
*/
public static final int VERSION_FIELD_OFFSET = 4;
/**
* Offset in the frame at which the flags field begins.
*/
public static final int FLAGS_FIELD_OFFSET = 5;
/**
* Offset in the frame at which the frame type field begins.
*/
public static final int TYPE_FIELD_OFFSET = 6;
/**
* Minimum length of any Aeron frame.
*/
public static final int MIN_HEADER_LENGTH = TYPE_FIELD_OFFSET + SIZE_OF_SHORT;
/**
* Default constructor which can later be used to wrap a frame.
*/
public HeaderFlyweight()
{
}
/**
* Construct a flyweight which wraps a {@link UnsafeBuffer} over the frame.
*
* @param buffer to wrap for the flyweight.
*/
public HeaderFlyweight(final UnsafeBuffer buffer)
{
super(buffer);
}
/**
* Construct a flyweight which wraps a {@link ByteBuffer} over the frame.
*
* @param buffer to wrap for the flyweight.
*/
public HeaderFlyweight(final ByteBuffer buffer)
{
super(buffer);
}
/**
* The version field value.
*
* @return version field value.
*/
public short version()
{
return (short)(getByte(VERSION_FIELD_OFFSET) & 0xFF);
}
/**
* Set the version field value.
*
* @param version field value to be set.
* @return this for a fluent API.
*/
public HeaderFlyweight version(final short version)
{
putByte(VERSION_FIELD_OFFSET, (byte)version);
return this;
}
/**
* The flags field value.
*
* @return the flags field value.
*/
public short flags()
{
return (short)(getByte(FLAGS_FIELD_OFFSET) & 0xFF);
}
/**
* Set the flags field value.
*
* @param flags field value.
* @return this for a fluent API.
*/
public HeaderFlyweight flags(final short flags)
{
putByte(FLAGS_FIELD_OFFSET, (byte)flags);
return this;
}
/**
* The type field value.
*
* @return the type field value.
*/
public int headerType()
{
return getShort(TYPE_FIELD_OFFSET, LITTLE_ENDIAN) & 0xFFFF;
}
/**
* Set the type field value.
*
* @param type field value.
* @return this for a fluent API.
*/
public HeaderFlyweight headerType(final int type)
{
putShort(TYPE_FIELD_OFFSET, (short)type, LITTLE_ENDIAN);
return this;
}
/**
* The length of the frame field value.
*
* @return length of the frame field value.
*/
public int frameLength()
{
return getInt(FRAME_LENGTH_FIELD_OFFSET, LITTLE_ENDIAN);
}
/**
* Set the length of the frame field value.
*
* @param length field value.
* @return this for a fluent API.
*/
public HeaderFlyweight frameLength(final int length)
{
putInt(FRAME_LENGTH_FIELD_OFFSET, length, LITTLE_ENDIAN);
return this;
}
/**
* Convert header flags to an array of chars to be human-readable.
*
* @param flags to be converted.
* @return header flags converted to an array of chars to be human-readable.
*/
public static char[] flagsToChars(final short flags)
{
final char[] chars = new char[]{ '0', '0', '0', '0', '0', '0', '0', '0' };
final int length = chars.length;
short mask = (short)(1 << (length - 1));
for (int i = 0; i < length; i++)
{
if ((flags & mask) == mask)
{
chars[i] = '1';
}
mask >>= 1;
}
return chars;
}
/**
* Append header flags to an {@link Appendable} to be human-readable.
*
* @param flags to be converted.
* @param appendable to append flags to.
*/
public static void appendFlagsAsChars(final short flags, final Appendable appendable)
{
final int length = 8;
short mask = (short)(1 << (length - 1));
try
{
for (int i = 0; i < length; i++)
{
appendable.append((flags & mask) == mask ? '1' : '0');
mask >>= 1;
}
}
catch (final IOException ex)
{
LangUtil.rethrowUnchecked(ex);
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy