php.java.bridge.http
Class ContextFactory

java.lang.Object
  php.java.bridge.SessionFactory
      php.java.bridge.http.ContextFactory

All Implemented Interfaces:

IContextFactory

public final class ContextFactory
extends SessionFactory
implements IContextFactory

Create session, jsr223 contexts.

The ContextFactory may keep a promise (a "proxy") which one may evaluate to a session reference (for PHP/JSP session sharing), and/or it may reference a "half-executed" bridge for local channel re-directs (for "high speed" communication links).

A unique context instance should be created for each request and destroyed when the request is done.

Clients of the PHP clients may attach additional data and run with a customized ContextFactory by using the visitor pattern, see accept(IContextFactoryVisitor).

The string ID of the instance should be passed to the client, which may pass it back together with the getSession request or the "local channel re-direct". If the former happens, we invoke the promise and return the session object to the client. Different promises can evaluate to the same session object. For local channel re-directs the ContextFactory is given to a ContextRunner which handles the local channel communication.

When a php client is not interested in a context for 5 seconds (checked every 10 minutes), the context is destroyed: a) switching from the HTTP tunnel to the local channel of the ContextRunner or b) switching from the fresh context created by the client of the PHP client to the recycled, persistent context, costs only one round-trip. The time for such a context switch is usually much less than 10ms unless either the php client or the client that waits for the php client is traced. If 5 seconds is not enough during debugging, change the ORPHANED_TIMEOUT.

In a shared environment with k web contexts there can be up to n*k active JavaBridge/ContextFactory instances (where n is the number of active php clients). All ContextFactories are kept in a shared, per-loader map. But the map can only be accessed via get(String, ICredentials), which checks if the ContextFactory belongs to the same ContextServer.

See Also:

ServletContextFactory, ContextServer, SessionFactory.TIMER_DURATION

Nested Class Summary

static interface

ContextFactory.ICredentials The credentials provided by the web context, usually this ContextFactory.

Field Summary

static java.lang.String

EMPTY_CONTEXT_NAME This context name can be used when a ContextFactory is used outside of a servlet environment

Fields inherited from class php.java.bridge.SessionFactory

TIMER_DURATION, TIMER_FREQ

Constructor Summary

ContextFactory(java.lang.String webContext)

Method Summary

void	accept(IContextFactoryVisitor visitor) Use this method to attach a visitor to the ContextFactory.
static IContextFactory	addNew() Create a new simple ContextFactory (a factory which creates an emulated JSR223 context) and add it to the list of context factories kept by this classloader.
static IContextFactory	addNew(java.lang.String webContext) Create a new ContextFactory and add it to the list of context factories kept by this classloader.
void	destroy() Destroy the factory
static void	destroyAll() Remove all context factories from the classloader.
static IContextFactory	get(java.lang.String id, ContextFactory.ICredentials server) Only for internal use.
JavaBridge	getBridge() Return the JavaBridge.
java.lang.Object	getContext() Returns the context.
java.lang.String	getId() Return the serializable ID of the context factory
ISession	getSession(java.lang.String name, boolean clientIsNew, int timeout) Return a standard session, shared with JSP
ISession	getSimpleSession(java.lang.String name, boolean clientIsNew, int timeout) Return a simple session which cannot be shared with JSP
void	recycle() Recycle the factory for new reqests.
void	recycle(ContextFactory target) Typically the visitor implements this method, it should attach itself to the target by calling target.accept(this).
void	recycle(java.lang.String id) Synchronize the current state with id.
static void	removeAll() Deprecated.
void	removeOrphaned() Removes the unused context factory from the classloader's list of context factories.
void	setBridge(JavaBridge bridge)
void	setContext(java.lang.Object context) Set the Context into this factory.
java.lang.String	toString()
void	waitFor() Wait until this context is finished.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

EMPTY_CONTEXT_NAME

public static final java.lang.String EMPTY_CONTEXT_NAME

This context name can be used when a ContextFactory is used outside of a servlet environment

See Also:

Constant Field Values

Constructor Detail

ContextFactory

public ContextFactory(java.lang.String webContext)

Method Detail

addNew

public static IContextFactory addNew(java.lang.String webContext)

Create a new ContextFactory and add it to the list of context factories kept by this classloader.

Parameters:

webContext - The current web context, use ContextFactory.EMPTY_CONTEXT if servlet web contexts are not available, config.getServletContext().getRealPath("") otherwise.

Returns:

The created ContextFactory.

See Also:

get(String, ICredentials)

addNew

public static IContextFactory addNew()

Create a new simple ContextFactory (a factory which creates an emulated JSR223 context) and add it to the list of context factories kept by this classloader.

Returns:

The created ContextFactory.

See Also:

get(String, ICredentials)

get

public static IContextFactory get(java.lang.String id,
                                  ContextFactory.ICredentials server)

Only for internal use. Returns the context factory associated with the given id

Parameters:

id - The ID

server - Your context server.

Returns:

The ContextFactory or null.

Throws:

java.lang.SecurityException - if id belongs to a different ContextServer.

See Also:

addNew(String)

recycle

public void recycle(ContextFactory target)

Description copied from interface: IContextFactory

Typically the visitor implements this method, it should attach itself to the target by calling target.accept(this).

Specified by:

recycle in interface IContextFactory

Parameters:

target - The persistent ContextFactory.

See Also:

IContextFactory.recycle(String), accept(IContextFactoryVisitor), IContextFactoryVisitor.visit(ContextFactory), SimpleContextFactory

recycle

public void recycle(java.lang.String id)
             throws java.lang.SecurityException

Description copied from interface: IContextFactory

Synchronize the current state with id.

When persistent connections are used, the bridge instances recycle their context factories (persistent php clients store their context id, so that they don't have to aquire a new one). However, a client of a php client may have passed a fresh context id. If this happened, the bridge calls this method, which may update the current context with the fresh values from id.

Typically the ContextFactory implements this method. It should find the ContextFactory for id, check that the Factory is not in use (and throw a SecurityException, if isInitialized() returns true), remove it by calling removeOrphaned() and call its recycle() method passing it the current ContextFactory.

Specified by:

recycle in interface IContextFactory

Parameters:

id - The fresh id

Throws:

java.lang.SecurityException - if the found ContextFactory is initialized.

See Also:

IContextFactory.recycle(ContextFactory), JavaBridge.recycle()

recycle

public void recycle()

Recycle the factory for new reqests.

Overrides:

recycle in class SessionFactory

destroy

public void destroy()

Description copied from class: SessionFactory

Destroy the factory

Specified by:

destroy in interface IContextFactory

Overrides:

destroy in class SessionFactory

removeAll

public static void removeAll()

Deprecated.

See Also:

destroyAll()

destroyAll

public static void destroyAll()

Remove all context factories from the classloader. May only be called by the ContextServer.

See Also:

ContextServer

waitFor

public void waitFor()
             throws java.lang.InterruptedException

Description copied from interface: IContextFactory

Wait until this context is finished.

Specified by:

waitFor in interface IContextFactory

Throws:

java.lang.InterruptedException

See Also:

ContextRunner

getId

public java.lang.String getId()

Description copied from interface: IContextFactory

Return the serializable ID of the context factory

Specified by:

getId in interface IContextFactory

Returns:

The ID

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getContext

public java.lang.Object getContext()

Returns the context.

Specified by:

getContext in interface IContextFactory

Overrides:

getContext in class SessionFactory

Returns:

The context or null.

See Also:

getContext()

setContext

public void setContext(java.lang.Object context)

Set the Context into this factory. Should be called by Context.addNew() only.

Specified by:

setContext in interface IContextFactory

Parameters:

context - The context.

See Also:

addNew(String)

setBridge

public void setBridge(JavaBridge bridge)

getBridge

public JavaBridge getBridge()

Description copied from interface: IContextFactory

Return the JavaBridge.

Specified by:

getBridge in interface IContextFactory

Returns:

Returns the bridge.

accept

public void accept(IContextFactoryVisitor visitor)

Use this method to attach a visitor to the ContextFactory.

Parameters:

visitor - The custom ContextFactory

getSimpleSession

public ISession getSimpleSession(java.lang.String name,
                                 boolean clientIsNew,
                                 int timeout)

Return a simple session which cannot be shared with JSP

Parameters:

name - The session name

clientIsNew - true, if the client wants a new session

timeout - expires in n seconds

getSession

public ISession getSession(java.lang.String name,
                           boolean clientIsNew,
                           int timeout)

Return a standard session, shared with JSP

Specified by:

getSession in interface IContextFactory

Overrides:

getSession in class SessionFactory

Parameters:

name - The session name

clientIsNew - true, if the client wants a new session

timeout - expires in n seconds

Returns:

The session

See Also:

ISession

removeOrphaned

public void removeOrphaned()

Description copied from interface: IContextFactory

Removes the unused context factory from the classloader's list of context factories.

Specified by:

removeOrphaned in interface IContextFactory