org.szegedi.spring.web.jsflow.support
Class FlowStateSerializer

java.lang.Object
  org.szegedi.spring.web.jsflow.support.FlowStateSerializer

All Implemented Interfaces:

org.springframework.beans.factory.InitializingBean, org.springframework.context.ApplicationContextAware

Direct Known Subclasses:

AbstractFlowStateStorage, HttpSessionFlowStateStorage

public abstract class FlowStateSerializer
extends java.lang.Object
implements org.springframework.context.ApplicationContextAware, org.springframework.beans.factory.InitializingBean

A class able to serialize and deserialize a continuation within a specified application context.

Version:

$Id: $

Author:

Attila Szegedi

Nested Class Summary

static interface	FlowStateSerializer.StubProvider An interface that can be implemented to provide further context-specific stubs.
static interface	FlowStateSerializer.StubResolver An interface that can be implemented to resolve further context-specific stubs.

Constructor Summary

FlowStateSerializer()

Method Summary

void	afterPropertiesSet()
protected org.mozilla.javascript.NativeContinuation	deserializeContinuation(byte[] b, FlowStateSerializer.StubResolver stubResolver) Deserializes a continuation.
ScriptStorage	getScriptStorage()
protected byte[]	serializeContinuation(org.mozilla.javascript.NativeContinuation state, java.util.Map stubbedFunctions, FlowStateSerializer.StubProvider stubProvider) Serializes a continuation.
void	setApplicationContext(org.springframework.context.ApplicationContext applicationContext)
void	setScriptStorage(ScriptStorage scriptStorage)

Methods inherited from class java.lang.Object

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

Constructor Detail

FlowStateSerializer

public FlowStateSerializer()

Method Detail

setScriptStorage

public void setScriptStorage(ScriptStorage scriptStorage)

getScriptStorage

public ScriptStorage getScriptStorage()

setApplicationContext

public void setApplicationContext(org.springframework.context.ApplicationContext applicationContext)

Specified by:

setApplicationContext in interface org.springframework.context.ApplicationContextAware

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.Exception

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Throws:

java.lang.Exception

serializeContinuation

protected byte[] serializeContinuation(org.mozilla.javascript.NativeContinuation state,
                                       java.util.Map stubbedFunctions,
                                       FlowStateSerializer.StubProvider stubProvider)
                                throws java.lang.Exception

Serializes a continuation. All script function object references as well as all references to objects defined in the application context will be replaced by named stubs. Additionally, a digital fingerprint of the internal JS bytecode representation of all JS functions on the continuation's stack is written.

Parameters:

state - the continuation to serialize

stubbedFunctions - a map that'll receive all mappings of stubs to functions. Can be used to locally deserialize a continuation and reconnect it with exact same functions that were current during serialization (thus making continuations immune to script reloading within a single JVM run). Can be null if tracking of stubs is not required.

Returns:

the serialized form

Throws:

java.lang.Exception

deserializeContinuation

protected org.mozilla.javascript.NativeContinuation deserializeContinuation(byte[] b,
                                                                            FlowStateSerializer.StubResolver stubResolver)
                                                                     throws java.lang.Exception

Deserializes a continuation. All stubs written during serialization are resolved to appropriate objects within this application context. Additionally, digital fingerprints of the functions on the continuation's stack are matched to the fingerprints of the same functions currently in the memory. If they don't match (i.e. the script was modified since the continuation was serialized), an exception is thrown to prevent undefined behaviour as the continuation's stack might now contain invalid return addresses.

Parameters:

b - the serialized continuation

Returns:

the deserialized continuation

Throws:

java.lang.Exception