com.aquenos.epics.jackie.common.protocol

Class ChannelAccessAccessRightsMessage

java.lang.Object

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

com.aquenos.epics.jackie.common.protocol.ChannelAccessAccessRightsMessage

public final class ChannelAccessAccessRightsMessage
extends ChannelAccessMessage

Representation of a CA_PROTO_ACCESS_RIGHTS message. This message is sent from a server to a client via TCP in order to communicate the access rights for a specific channel. This information might be used by the client to avoid operations that would be denied due to access control rules being in effect.

Author:

Sebastian Marsching

See Also:

ChannelAccessCommand.CA_PROTO_ACCESS_RIGHTS

Field Summary

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

command, originalMessageHeader

Constructor Summary

Constructors

Constructor and Description
ChannelAccessAccessRightsMessage(int cid, boolean mayRead, boolean mayWrite) Constructor for creating a CA_PROTO_ACCESS_RIGHTS message.

Method Summary

Modifier and Type	Method and Description
protected static ChannelAccessAccessRightsMessage	deserialize(ChannelAccessMessageHeader messageHeader, ByteSource byteSource) 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.
int	getChannelCID() Returns the channel CID used by the client.
int	hashCode() Returns a hash code value for this message.
boolean	isMayRead() Returns a flag indicating whether the client is allowed to read from the channel.
boolean	isMayWrite() Returns a flag indicating whether the client is allowed to write to the channel.
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

ChannelAccessAccessRightsMessage

public ChannelAccessAccessRightsMessage(int cid,
                                        boolean mayRead,
                                        boolean mayWrite)

Constructor for creating a CA_PROTO_ACCESS_RIGHTS message.

Parameters:

cid - the channel CID. This is the identifier used by the client to identify the channel.

mayRead - if true the client is allowed to read from the channel.

mayWrite - if true the client is allowed to write to the channel.

Method Detail

getChannelCID

public int getChannelCID()

Returns the channel CID used by the client. This is the identifier that the client uses to identify the channel. This number might be negative or zero.

Returns:

channel CID assigned to the channel by the client.

isMayRead

public boolean isMayRead()

Returns a flag indicating whether the client is allowed to read from the channel.

Returns:

true if the client may read from the channel, false otherwise.

isMayWrite

public boolean isMayWrite()

Returns a flag indicating whether the client is allowed to write to the channel.

Returns:

true if the client may write to the channel, false otherwise.

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 ChannelAccessAccessRightsMessage deserialize(ChannelAccessMessageHeader messageHeader,
                                                              ByteSource byteSource)

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).

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).