org.springframework.webflow.conversation.impl
Class SessionBindingConversationManager

java.lang.Object
  org.springframework.webflow.conversation.impl.SessionBindingConversationManager

All Implemented Interfaces:

ConversationManager

public class SessionBindingConversationManager
extends java.lang.Object
implements ConversationManager

Simple implementation of a conversation manager that stores conversations in the session attribute map.

Using the maxConversations property, you can limit the number of concurrently active conversations allowed in a single session. If the maximum is exceeded, the conversation manager will automatically end the oldest conversation. The default is 5, which should be fine for most situations. Set it to -1 for no limit. Setting maxConversations to 1 allows easy resource cleanup in situations where there should only be one active conversation per session.

Author:

Erwin Vervaet

Constructor Summary

SessionBindingConversationManager()

Method Summary

Conversation	beginConversation(ConversationParameters conversationParameters) Begin a new conversation.
protected ConversationContainer	createConversationContainer()
Conversation	getConversation(ConversationId id) Get the conversation with the provided id.
protected ConversationContainer	getConversationContainer() Obtain the conversation container from the session.
int	getLockTimeoutSeconds() Returns the time period that can elapse before a timeout occurs on an attempt to acquire a conversation lock.
int	getMaxConversations() Returns the maximum number of allowed concurrent conversations.
java.lang.String	getSessionKey() Returns the key this conversation manager uses to store conversation data in the session.
ConversationId	parseConversationId(java.lang.String encodedId) Parse the string-encoded conversationId into its object form.
void	setLockTimeoutSeconds(int lockTimeoutSeconds) Sets the time period that can elapse before a timeout occurs on an attempt to acquire a conversation lock.
void	setMaxConversations(int maxConversations) Set the maximum number of allowed concurrent conversations.
void	setSessionKey(java.lang.String sessionKey) Sets the key this conversation manager uses to store conversation data in the session.

Methods inherited from class java.lang.Object

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

Constructor Detail

SessionBindingConversationManager

public SessionBindingConversationManager()

Method Detail

getSessionKey

public java.lang.String getSessionKey()

Returns the key this conversation manager uses to store conversation data in the session.

Returns:

the session key

setSessionKey

public void setSessionKey(java.lang.String sessionKey)

Sets the key this conversation manager uses to store conversation data in the session. If multiple session binding conversation managers are used in the same web application to back independent flow executors, this value should be unique among them.

Parameters:

sessionKey - the session key

getMaxConversations

public int getMaxConversations()

Returns the maximum number of allowed concurrent conversations. The default is 5.

setMaxConversations

public void setMaxConversations(int maxConversations)

Set the maximum number of allowed concurrent conversations. Set to -1 for no limit. The default is 5.

getLockTimeoutSeconds

public int getLockTimeoutSeconds()

Returns the time period that can elapse before a timeout occurs on an attempt to acquire a conversation lock. The default is 30 seconds.

setLockTimeoutSeconds

public void setLockTimeoutSeconds(int lockTimeoutSeconds)

Sets the time period that can elapse before a timeout occurs on an attempt to acquire a conversation lock. The default is 30 seconds.

Parameters:

lockTimeoutSeconds - the timeout period in seconds

beginConversation

public Conversation beginConversation(ConversationParameters conversationParameters)
                               throws ConversationException

Description copied from interface: ConversationManager

Begin a new conversation.

Specified by:

beginConversation in interface ConversationManager

Parameters:

conversationParameters - descriptive conversation parameters

Returns:

a service interface allowing access to the conversation context

Throws:

ConversationException - an exception occured

getConversation

public Conversation getConversation(ConversationId id)
                             throws ConversationException

Description copied from interface: ConversationManager

Get the conversation with the provided id.

Implementors should take care to manage conversation identity correctly. Although it is not strictly required to return the same (==) Conversation object every time this method is called with a particular conversation id in a single execution thread, callers will expect to recieve an object that allows them to manipulate the identified conversation. In other words, the following is legal ConversationManager client code:

        ConversationManager manager = ...;
        ConversationId id = ...;
        Conversation conv = manager.getConversation(id);
  conv.lock();
  try {
        Conversation localReference = manager.getConversation(id);
        // no need to lock since conversation 'id' is already locked
        // even though possibly conv != localReference
        localReference.putAttribute("foo", "bar");
        Object foo = conv.getAttribute("foo");
        }
        finally {
                conv.unlock();
        }
 

Specified by:

getConversation in interface ConversationManager

Parameters:

id - the conversation id

Returns:

the conversation

Throws:

NoSuchConversationException - the id provided was invalid

ConversationException

parseConversationId

public ConversationId parseConversationId(java.lang.String encodedId)
                                   throws ConversationException

Description copied from interface: ConversationManager

Parse the string-encoded conversationId into its object form. Essentially, the reverse of ConversationId.toString().

Specified by:

parseConversationId in interface ConversationManager

Parameters:

encodedId - the encoded id

Returns:

the parsed conversation id

Throws:

ConversationException - an exception occured parsing the id

createConversationContainer

protected ConversationContainer createConversationContainer()

getConversationContainer

protected final ConversationContainer getConversationContainer()

Obtain the conversation container from the session. Create a new empty container and add it to the session if no existing container can be found.