org.sandev.tools.util
Class JMSMessager

java.lang.Object
  org.sandev.tools.util.DirectCallMessager
      org.sandev.tools.util.JMSMessager

All Implemented Interfaces:

javax.jms.MessageListener, org.sandev.basics.nodecommon.Messager

public class JMSMessager
extends DirectCallMessager
implements javax.jms.MessageListener

A Messager implementation for use over JMS. This is tested using OpenJMS. Extends DirectCallMessager to provide optimized messaging for nodes on the same server.

Field Summary

protected org.sandev.basics.nodecommon.CharSerializer	charSerializer The CharSerializer we use for converting objects to text and back.
protected javax.jms.TopicConnection	connection Single connection to the provider is all we need
protected javax.naming.Context	context
protected javax.jms.TopicSession	session Use a single TopicSession since we're not using transactions
protected java.util.Hashtable	subscriberMap Map of topic name to TopicSubscribers

Fields inherited from class org.sandev.tools.util.DirectCallMessager

ourInstance, ourNode, subTable

Fields inherited from interface org.sandev.basics.nodecommon.Messager

MODE_DIRECT, MODE_INVALID, MODE_SECURE, OPTIMIZE_IF_POSSIBLE, OPTIMIZE_NEVER, WIRE_BASICSECURITY, WIRE_SECURECOMMS, WIRE_TRANSPORTONLY

Constructor Summary

JMSMessager()
Default ctor does nothing.

Method Summary

protected javax.jms.TopicSession	createSession() Create a JMS TopicSession.
protected javax.jms.TopicConnection	createTopicConnection() Create and start a JMS TopicConnection.
protected org.sandev.basics.structs.SandMessage	deserializeJMSMessage(javax.jms.TextMessage message) Deserialize a SandMessage serialized as a JMS TextMessage.
protected void	doDeliver(javax.jms.Message message) Deserialize a JMS message and pass it to the node's deliver method.
protected org.sandev.basics.structs.SandMessage	doQuery(org.sandev.basics.structs.SandMessage msg, java.lang.String topicName) Perform a synchronous query on the given Topic.
protected org.sandev.basics.structs.SandMessage	doQuery(org.sandev.basics.structs.SandMessage msg, java.lang.String recipient, int optimize) Query the specified node.
protected void	doReceive(javax.jms.Message message) Deserialize a JMS message, pass it to the node's receive method, and return the response to the Topic specified in the JMS message's replyTo field.
protected void	doSend(org.sandev.basics.structs.SandMessage msg, int optimize) Send the message.
protected void	doSend(org.sandev.basics.structs.SandMessage msg, java.lang.String topicName) Send a SandMessage to the specified JMS topic.
protected void	doSubscribe(org.sandev.basics.nodecommon.Messageable node, java.lang.String msgClass, java.lang.String sender, int optimize) Make the subscription happen.
protected void	doUnsubscribe(org.sandev.basics.nodecommon.Messageable node, java.lang.String msgClass, java.lang.String sender, int optimize) Make the subscription go away.
org.sandev.basics.nodecommon.CharSerializer	getCharSerializer() accessor for charSerializer
protected javax.naming.Context	getContext() Create a JNDI Context for JMS Topic lookups.
protected int	getImplementationWireSecurity() JMS doesn't specify wire-level security (although some providers support secure transports like SSL).
protected javax.jms.Topic	getTopic(java.lang.String topic) Lookup the JMS Topic with the given topic name.
void	init(org.sandev.basics.nodecommon.Messageable node, org.sandev.basics.structs.NodeInstance instance)
protected void	jmsSubscribe(java.lang.String topicName) Subscribe this messager to a JMS topic.
protected void	jmsUnsubscribe(java.lang.String topicName) Unsubscribe this messager from a JMS topic.
void	onMessage(javax.jms.Message message) Receive a JMS Message, unpack it, and pass it to the node.
protected java.lang.String	serializeSandMessage(org.sandev.basics.structs.SandMessage sandMessage) Serialize a SandMessage as a text string for inclusion in a JMS TextMessage.
void	setCharSerializer(org.sandev.basics.nodecommon.CharSerializer val) mutator for charSerializer
void	shutdown()

Methods inherited from class org.sandev.tools.util.DirectCallMessager

addSubscriber, doSend, error, getMessageable, getOurInstance, getOurNode, getSubTable, getWireSecurity, info, query, queryReceiver, removeSubscriber, send, setOurInstance, setOurNode, subscribe, unsubscribe

Methods inherited from class java.lang.Object

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

Field Detail

context

protected javax.naming.Context context

connection

protected javax.jms.TopicConnection connection

Single connection to the provider is all we need

session

protected javax.jms.TopicSession session

Use a single TopicSession since we're not using transactions

subscriberMap

protected java.util.Hashtable subscriberMap

Map of topic name to TopicSubscribers

charSerializer

protected org.sandev.basics.nodecommon.CharSerializer charSerializer

The CharSerializer we use for converting objects to text and back.

Constructor Detail

JMSMessager

public JMSMessager()

Default ctor does nothing.

Method Detail

getCharSerializer

public org.sandev.basics.nodecommon.CharSerializer getCharSerializer()

accessor for charSerializer

setCharSerializer

public void setCharSerializer(org.sandev.basics.nodecommon.CharSerializer val)

mutator for charSerializer

init

public void init(org.sandev.basics.nodecommon.Messageable node,
                 org.sandev.basics.structs.NodeInstance instance)
          throws org.sandev.basics.nodecommon.MessagerException

Specified by:

init in interface org.sandev.basics.nodecommon.Messager

Overrides:

init in class DirectCallMessager

Throws:

org.sandev.basics.nodecommon.MessagerException

shutdown

public void shutdown()

Specified by:

shutdown in interface org.sandev.basics.nodecommon.Messager

Overrides:

shutdown in class DirectCallMessager

onMessage

public void onMessage(javax.jms.Message message)

Receive a JMS Message, unpack it, and pass it to the node. If the JMS message has a replyTo destination set, treats the message as a query and passes it to the node's query method. Otherwise passes the message to the node's deliver method.

Specified by:

onMessage in interface javax.jms.MessageListener

getImplementationWireSecurity

protected int getImplementationWireSecurity()

JMS doesn't specify wire-level security (although some providers support secure transports like SSL).

Overrides:

getImplementationWireSecurity in class DirectCallMessager

doSubscribe

protected void doSubscribe(org.sandev.basics.nodecommon.Messageable node,
                           java.lang.String msgClass,
                           java.lang.String sender,
                           int optimize)
                    throws org.sandev.basics.nodecommon.MessagerException

Make the subscription happen.

Overrides:

doSubscribe in class DirectCallMessager

Throws:

org.sandev.basics.nodecommon.MessagerException

doUnsubscribe

protected void doUnsubscribe(org.sandev.basics.nodecommon.Messageable node,
                             java.lang.String msgClass,
                             java.lang.String sender,
                             int optimize)
                      throws org.sandev.basics.nodecommon.MessagerException

Make the subscription go away.

Overrides:

doUnsubscribe in class DirectCallMessager

Throws:

org.sandev.basics.nodecommon.MessagerException

doSend

protected void doSend(org.sandev.basics.structs.SandMessage msg,
                      int optimize)
               throws org.sandev.basics.nodecommon.MessagerException

Send the message.

Overrides:

doSend in class DirectCallMessager

Throws:

org.sandev.basics.nodecommon.MessagerException

doSend

protected void doSend(org.sandev.basics.structs.SandMessage msg,
                      java.lang.String topicName)
               throws org.sandev.basics.nodecommon.MessagerException

Send a SandMessage to the specified JMS topic.

Throws:

org.sandev.basics.nodecommon.MessagerException

doQuery

protected org.sandev.basics.structs.SandMessage doQuery(org.sandev.basics.structs.SandMessage msg,
                                                        java.lang.String recipient,
                                                        int optimize)
                                                 throws org.sandev.basics.nodecommon.MessagerException

Query the specified node.

Overrides:

doQuery in class DirectCallMessager

Throws:

org.sandev.basics.nodecommon.MessagerException

doQuery

protected org.sandev.basics.structs.SandMessage doQuery(org.sandev.basics.structs.SandMessage msg,
                                                        java.lang.String topicName)
                                                 throws org.sandev.basics.nodecommon.MessagerException

Perform a synchronous query on the given Topic. Creates a temporary topic and waits for the response on that topic.

Throws:

org.sandev.basics.nodecommon.MessagerException

doReceive

protected void doReceive(javax.jms.Message message)
                  throws javax.jms.JMSException,
                         java.io.IOException,
                         org.sandev.basics.structs.SandException

Deserialize a JMS message, pass it to the node's receive method, and return the response to the Topic specified in the JMS message's replyTo field.

Throws:

javax.jms.JMSException

java.io.IOException

org.sandev.basics.structs.SandException

doDeliver

protected void doDeliver(javax.jms.Message message)
                  throws javax.jms.JMSException,
                         java.io.IOException,
                         org.sandev.basics.structs.SandException

Deserialize a JMS message and pass it to the node's deliver method.

Throws:

javax.jms.JMSException

java.io.IOException

org.sandev.basics.structs.SandException

getContext

protected javax.naming.Context getContext()
                                   throws org.sandev.basics.nodecommon.MessagerException

Create a JNDI Context for JMS Topic lookups. With OpenJMS, this uses OpenJMS JNDI provider because the OpenJMS server needs to be restarted independently of the container JNDI server.

Throws:

org.sandev.basics.nodecommon.MessagerException

createTopicConnection

protected javax.jms.TopicConnection createTopicConnection()
                                                   throws org.sandev.basics.nodecommon.MessagerException

Create and start a JMS TopicConnection.

Throws:

org.sandev.basics.nodecommon.MessagerException

createSession

protected javax.jms.TopicSession createSession()
                                        throws org.sandev.basics.nodecommon.MessagerException

Create a JMS TopicSession.

Throws:

org.sandev.basics.nodecommon.MessagerException

getTopic

protected javax.jms.Topic getTopic(java.lang.String topic)
                            throws javax.naming.NamingException

Lookup the JMS Topic with the given topic name.

Throws:

javax.naming.NamingException

jmsSubscribe

protected void jmsSubscribe(java.lang.String topicName)
                     throws org.sandev.basics.nodecommon.MessagerException

Subscribe this messager to a JMS topic.

Throws:

org.sandev.basics.nodecommon.MessagerException

jmsUnsubscribe

protected void jmsUnsubscribe(java.lang.String topicName)
                       throws org.sandev.basics.nodecommon.MessagerException

Unsubscribe this messager from a JMS topic. The messager must already be a subscriber to the topic.

Throws:

org.sandev.basics.nodecommon.MessagerException

serializeSandMessage

protected java.lang.String serializeSandMessage(org.sandev.basics.structs.SandMessage sandMessage)
                                         throws java.io.IOException

Serialize a SandMessage as a text string for inclusion in a JMS TextMessage.

Throws:

java.io.IOException

deserializeJMSMessage

protected org.sandev.basics.structs.SandMessage deserializeJMSMessage(javax.jms.TextMessage message)
                                                               throws javax.jms.JMSException,
                                                                      java.io.IOException

Deserialize a SandMessage serialized as a JMS TextMessage.

Throws:

javax.jms.JMSException

java.io.IOException