org.apache.river.discovery

Class DiscoveryV1

java.lang.Object

org.apache.river.discovery.Discovery

org.apache.river.discovery.DiscoveryV1

class DiscoveryV1
extends Discovery

Class providing methods for implementing discovery protocol version 1.

Field Summary

Fields

Modifier and Type	Field and Description
private static DiscoveryV1	instance
private static Logger	logger
private static int	SERVICE_ID_LEN

Fields inherited from class org.apache.river.discovery.Discovery

MIN_MAX_PACKET_SIZE, PROTOCOL_VERSION_1, PROTOCOL_VERSION_2

Constructor Summary

Constructors

Constructor and Description
DiscoveryV1()

Method Summary

Modifier and Type	Method and Description
private static void	checkConstraints(InvocationConstraints constraints)
MulticastAnnouncement	decodeMulticastAnnouncement(DatagramPacket packet, InvocationConstraints constraints) Decodes the multicast announcement data contained in the given datagram in a manner that satisfies the specified constraints, returning a MulticastAnnouncement instance that contains the decoded data.
MulticastRequest	decodeMulticastRequest(DatagramPacket packet, InvocationConstraints constraints, ClientSubjectChecker checker) Decodes the multicast request data contained in the given datagram in a manner that satisfies the specified constraints and client subject checker (if any), returning a MulticastRequest instance that contains the decoded data.
UnicastResponse	doUnicastDiscovery(Socket socket, InvocationConstraints constraints, ClassLoader defaultLoader, ClassLoader verifierLoader, Collection context) Performs the client side of unicast discovery, obtaining the returned response data over the provided socket using the given default and codebase verifier class loaders and collection of object stream context objects in a manner that satisfies the specified constraints.
private static DatagramPacket[]	encode(MulticastAnnouncement announcement, int maxPacketSize, InvocationConstraints constraints)
private static DatagramPacket[]	encode(MulticastRequest request, int maxPacketSize, InvocationConstraints constraints)
EncodeIterator	encodeMulticastAnnouncement(MulticastAnnouncement announcement, int maxPacketSize, InvocationConstraints constraints) Returns an iterator which can be used to encode the given multicast announcement data into sets of DatagramPackets, each bounded in length by the specified maximum packet size, in a manner that satisfies the given constraints.
EncodeIterator	encodeMulticastRequest(MulticastRequest request, int maxPacketSize, InvocationConstraints constraints) Returns an iterator which can be used to encode the given multicast request data into sets of DatagramPackets, each bounded in length by the specified maximum packet size, in a manner that satisfies the given constraints.
(package private) static DiscoveryV1	getInstance()
void	handleUnicastDiscovery(UnicastResponse response, Socket socket, InvocationConstraints constraints, ClientSubjectChecker checker, Collection context) Handles the server side of unicast discovery, transmitting the given response data over the provided socket using the given collection of object stream context objects in a manner that satisfies the specified constraints and client subject checker (if any).
String	toString()

Methods inherited from class org.apache.river.discovery.Discovery

decodeMulticastAnnouncement, decodeMulticastRequest, getProtocol1, getProtocol2, getProtocol2

Methods inherited from class java.lang.Object

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

Field Detail

SERVICE_ID_LEN

private static final int SERVICE_ID_LEN

See Also:

Constant Field Values

instance

private static final DiscoveryV1 instance

logger

private static final Logger logger

Constructor Detail

DiscoveryV1

DiscoveryV1()

Method Detail

getInstance

static DiscoveryV1 getInstance()

encodeMulticastRequest

public EncodeIterator encodeMulticastRequest(MulticastRequest request,
                                             int maxPacketSize,
                                             InvocationConstraints constraints)

Description copied from class: Discovery

Returns an iterator which can be used to encode the given multicast request data into sets of DatagramPackets, each bounded in length by the specified maximum packet size, in a manner that satisfies the given constraints. null constraints are considered equivalent to empty constraints. The destination of each DatagramPacket produced by the returned iterator is set to the address returned by Constants.getRequestAddress(), with the value of Constants.discoveryPort used as the destination port.

Specified by:

encodeMulticastRequest in class Discovery

Parameters:

request - the request data to encode

maxPacketSize - the maximum size of packets to produce

constraints - the constraints to apply when encoding the data, or null

Returns:

an iterator to use for encoding the data

encode

private static DatagramPacket[] encode(MulticastRequest request,
                                       int maxPacketSize,
                                       InvocationConstraints constraints)
                                throws IOException

Throws:

IOException

decodeMulticastRequest

public MulticastRequest decodeMulticastRequest(DatagramPacket packet,
                                               InvocationConstraints constraints,
                                               ClientSubjectChecker checker)
                                        throws IOException

Description copied from class: Discovery

Decodes the multicast request data contained in the given datagram in a manner that satisfies the specified constraints and client subject checker (if any), returning a MulticastRequest instance that contains the decoded data. null constraints are considered equivalent to empty constraints. All the specified constraints are checked before this method returns.

Specified by:

decodeMulticastRequest in class Discovery

Parameters:

packet - the packet to decode

constraints - the constraints to apply when decoding the packet, or null

checker - the object to use to check the client subject, or null

Returns:

the decoded multicast request data

Throws:

IOException - if an error occurs in interpreting the data

UnsupportedConstraintException - if unable to satisfy the specified constraints

encodeMulticastAnnouncement

public EncodeIterator encodeMulticastAnnouncement(MulticastAnnouncement announcement,
                                                  int maxPacketSize,
                                                  InvocationConstraints constraints)

Description copied from class: Discovery

Returns an iterator which can be used to encode the given multicast announcement data into sets of DatagramPackets, each bounded in length by the specified maximum packet size, in a manner that satisfies the given constraints. null constraints are considered equivalent to empty constraints. The destination of each DatagramPacket produced by the returned iterator is set to the address returned by Constants.getAnnouncementAddress(), with the value of Constants.discoveryPort used as the destination port.

Specified by:

encodeMulticastAnnouncement in class Discovery

Parameters:

announcement - the announcement data to encode

maxPacketSize - the maximum size of packets to produce

constraints - the constraints to apply when encoding the data, or null

Returns:

an iterator to use for encoding the data

encode

private static DatagramPacket[] encode(MulticastAnnouncement announcement,
                                       int maxPacketSize,
                                       InvocationConstraints constraints)
                                throws IOException

Throws:

IOException

decodeMulticastAnnouncement

public MulticastAnnouncement decodeMulticastAnnouncement(DatagramPacket packet,
                                                         InvocationConstraints constraints)
                                                  throws IOException

Description copied from class: Discovery

Decodes the multicast announcement data contained in the given datagram in a manner that satisfies the specified constraints, returning a MulticastAnnouncement instance that contains the decoded data. null constraints are considered equivalent to empty constraints. All the specified constraints are checked before this method returns.

Specified by:

decodeMulticastAnnouncement in class Discovery

Parameters:

packet - the packet to decode

constraints - the constraints to apply when decoding the packet, or null

Returns:

the decoded multicast announcement data

Throws:

IOException - if an error occurs in interpreting the data

UnsupportedConstraintException - if unable to satisfy the specified constraints

doUnicastDiscovery

public UnicastResponse doUnicastDiscovery(Socket socket,
                                          InvocationConstraints constraints,
                                          ClassLoader defaultLoader,
                                          ClassLoader verifierLoader,
                                          Collection context)
                                   throws IOException,
                                          ClassNotFoundException

Description copied from class: Discovery

Performs the client side of unicast discovery, obtaining the returned response data over the provided socket using the given default and codebase verifier class loaders and collection of object stream context objects in a manner that satisfies the specified constraints. null constraints are considered equivalent to empty constraints.

Specified by:

doUnicastDiscovery in class Discovery

Parameters:

socket - the socket on which to perform unicast discovery

constraints - the constraints to apply to unicast discovery, or null

defaultLoader - the class loader value (possibly null) to be passed as the defaultLoader argument to RMIClassLoader methods when unmarshalling the registrar proxy

verifierLoader - the class loader value (possibly null) to pass to Security.verifyCodebaseIntegrity, if codebase integrity verification is used when unmarshalling the registrar proxy

context - the collection of context information objects (possibly null) to use when unmarshalling the registrar proxy

Returns:

the received unicast response data

Throws:

IOException - if an error occurs in interpreting received data or in formatting data to send

UnsupportedConstraintException - if unable to satisfy the specified constraints

ClassNotFoundException - if the class of the discovered registrar cannot be resolved

handleUnicastDiscovery

public void handleUnicastDiscovery(UnicastResponse response,
                                   Socket socket,
                                   InvocationConstraints constraints,
                                   ClientSubjectChecker checker,
                                   Collection context)
                            throws IOException

Description copied from class: Discovery

Handles the server side of unicast discovery, transmitting the given response data over the provided socket using the given collection of object stream context objects in a manner that satisfies the specified constraints and client subject checker (if any). This method assumes that the protocol version number has already been consumed from the socket, but that no further processing of the connection has occurred. null constraints are considered equivalent to empty constraints.

Specified by:

handleUnicastDiscovery in class Discovery

Parameters:

response - the unicast response data to transmit

socket - the socket on which to handle unicast discovery

constraints - the constraints to apply to unicast discovery, or null

checker - the object to use to check the client subject, or null

context - the collection of context information objects to use when marshalling the registrar proxy

Throws:

IOException - if the protocol handshake fails, or if an error occurs in interpreting received data or in formatting data to send

UnsupportedConstraintException - if unable to satisfy the specified constraints

toString

public String toString()

Overrides:

toString in class Object

checkConstraints

private static void checkConstraints(InvocationConstraints constraints)
                              throws UnsupportedConstraintException

Throws:

UnsupportedConstraintException