com.aquenos.epics.jackie.common.protocol

Class ChannelAccessHostNameMessage

java.lang.Object

com.aquenos.epics.jackie.common.protocol.ChannelAccessMessage

com.aquenos.epics.jackie.common.protocol.ChannelAccessHostNameMessage

public final class ChannelAccessHostNameMessage
extends ChannelAccessMessage

Representation of a CA_PROTO_HOST_NAME message. This message is sent from a client to a server via TCP in order to communicate the name of the client computer. This information might be used for access control.

Author:

Sebastian Marsching

See Also:

ChannelAccessCommand.CA_PROTO_HOST_NAME

Field Summary

Fields inherited from class com.aquenos.epics.jackie.common.protocol.ChannelAccessMessage

command, originalMessageHeader

Constructor Summary

Constructors

Constructor and Description
ChannelAccessHostNameMessage(java.lang.String hostName) Constructor for creating a CA_PROTO_HOST_NAME message.

Method Summary

Modifier and Type	Method and Description
protected static ChannelAccessHostNameMessage	deserialize(ChannelAccessMessageHeader messageHeader, ByteSource byteSource, boolean headerOnly, java.nio.charset.Charset deserialize) Constructs a message from a header and a byte source.
boolean	equals(java.lang.Object obj) Tells whether the specified object represents the same message.
java.lang.String	getHostName() Returns the name of the host on which the Channel Access client is running.
int	hashCode() Returns a hash code value for this message.
protected void	serialize(ByteSink byteSink, ChannelAccessVersion version, int maxPayloadSize, java.nio.charset.Charset charset) Serializes this message to a byte sink.
java.lang.String	toString() Returns a string representation of this message.
protected void	verify(ChannelAccessVersion version, int maxPayloadSize, java.nio.charset.Charset charset) Verifies that this message can be serialized.

Methods inherited from class com.aquenos.epics.jackie.common.protocol.ChannelAccessMessage

addByteArrayToStringBuilder, calculatePaddingSize, getCommand, getOriginalMessageHeader, hasOriginalMessageHeader, serializeHeader, verifyHeader

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ChannelAccessHostNameMessage

public ChannelAccessHostNameMessage(java.lang.String hostName)

Constructor for creating a CA_PROTO_HOST_NAME message.

Parameters:

hostName - name of the client computer.

Method Detail

getHostName

public java.lang.String getHostName()

Returns the name of the host on which the Channel Access client is running.

Returns:

host name of the client computer. Might be null if this message instance has been reconstructed without its payload (as part of the payload of an error message).

serialize

protected void serialize(ByteSink byteSink,
                         ChannelAccessVersion version,
                         int maxPayloadSize,
                         java.nio.charset.Charset charset)

Description copied from class: ChannelAccessMessage

Serializes this message to a byte sink. This method is only intended to be used by ChannelAccessMessageCodec.

Specified by:

serialize in class ChannelAccessMessage

Parameters:

byteSink - byte sink that is used for writing the serialized data.

version - protocol version to stay compatible with. This is the protocol version of the peer the message is sent to.

maxPayloadSize - maximum size of the payload.

charset - encoding to use for serializing the string data (e.g. channel names, error strings, string data-values).

verify

protected void verify(ChannelAccessVersion version,
                      int maxPayloadSize,
                      java.nio.charset.Charset charset)

Description copied from class: ChannelAccessMessage

Verifies that this message can be serialized. This method is only intended to be used by ChannelAccessMessageCodec.

Overrides:

verify in class ChannelAccessMessage

Parameters:

version - protocol version to stay compatible with. This is the protocol version of the peer the message is sent to.

maxPayloadSize - maximum size of the payload.

charset - encoding to use for serializing the string data (e.g. channel names, error strings, string data-values).

equals

public boolean equals(java.lang.Object obj)

Description copied from class: ChannelAccessMessage

Tells whether the specified object represents the same message.

Two messages are considered equal if they are of the same type and have the same headers and payload. For comparing the types, the actual Java type and not just the Channel Access command is compared.

Overrides:

equals in class ChannelAccessMessage

Parameters:

obj - reference object with which this object is compared.

Returns:

true if obj is a message that is of the same type and has the same headers and payload as this message. false if obj is null or of a different type than this message or differs in the headers or payload.

hashCode

public int hashCode()

Description copied from class: ChannelAccessMessage

Returns a hash code value for this message. This method is supported for the benefit of hash tables. The hash code is calculated as a combination of the hash codes of this messages headers (including the Channel Access command) and its payload (if present).

If two messages are equal (as indicated by the return value of ChannelAccessMessage.equals(Object)), they also have the same hash code. However, the fact that two messages have the same hash code does not imply that they are equal.

Overrides:

hashCode in class ChannelAccessMessage

Returns:

hash code suitable for use by a hash table.

toString

public java.lang.String toString()

Description copied from class: ChannelAccessMessage

Returns a string representation of this message. The string representation contains the messages command, its header fields (if relevant for the command type) and its payload if present.

Overrides:

toString in class ChannelAccessMessage

Returns:

string representation of this message.

deserialize

protected static ChannelAccessHostNameMessage deserialize(ChannelAccessMessageHeader messageHeader,
                                                          ByteSource byteSource,
                                                          boolean headerOnly,
                                                          java.nio.charset.Charset deserialize)

Constructs a message from a header and a byte source. This method is only intended for use by ChannelAccessMessageCodec.

Parameters:

messageHeader - CA message header.

byteSource - byte source for reading the message's payload (if any).

headerOnly - if true this method will not try to read the payload but just read the header. This is useful for reading a message that is sent in the payload of a ChannelAccessErrorMessage. Such a message will have all headers but no payload (even so the payload size might be non-zero).

deserialize - encoding to use for deserializing the host name. Usually, host names should consist of ASCII characters only, however this is not strictly enforced by the protocol, so the encoding might matter.

Returns:

message constructed from the data in the header and the payload read from the byte source.

Throws:

java.nio.BufferUnderflowException - if there is not enough data in the byte source to read the complete message (including the payload).