org.apache.cocoon.components.flow
Class AbstractInterpreter

java.lang.Object
  org.apache.cocoon.util.AbstractLogEnabled
      org.apache.cocoon.components.flow.AbstractInterpreter

All Implemented Interfaces:

Configurable, Contextualizable, Disposable, org.apache.cocoon.components.flow.Interpreter, Serviceable, SingleThreaded

public abstract class AbstractInterpreter

extends org.apache.cocoon.util.AbstractLogEnabled

implements Serviceable, Contextualizable, org.apache.cocoon.components.flow.Interpreter, SingleThreaded, Configurable, Disposable

Abstract superclass for various scripting languages used by Cocoon for flow control. Defines some useful behavior like the ability to reload script files if they get modified (useful when doing development), and passing the control to Cocoon's sitemap for result page generation.

Flow intrepreters belonging to different sitemaps should be isolated. To achieve this, class implements the SingleThreaded. Since the sitemap engine looks up the flow intepreter once at sitemap build time, this ensures that each sitemap will use a different instance of this class. But that instance will handle all flow calls for a given sitemap, and must therefore be thread safe.

Since:

March 15, 2002

Version:

$Id: AbstractInterpreter.html 1304280 2012-03-23 11:18:01Z ilgrosso $

Nested Class Summary

Nested classes inherited from class org.apache.cocoon.components.flow.Interpreter

org.apache.cocoon.components.flow.Interpreter.Argument

Field Summary

protected Context	avalonContext
protected long	checkTime Interval between two checks for modified script files.
protected org.apache.cocoon.components.flow.ContinuationsManager	continuationsMgr
protected ServiceManager	manager
protected ArrayList	needResolve List of source locations that need to be resolved.
protected org.apache.cocoon.el.objectmodel.ObjectModel	newObjectModel
protected org.apache.cocoon.processing.ProcessInfoProvider	processInfoProvider
protected boolean	reloadScripts Whether reloading of scripts should be done.
protected org.apache.cocoon.configuration.Settings	settings The settings of Cocoon.

Fields inherited from interface org.apache.cocoon.components.flow.Interpreter

ROLE

Constructor Summary

AbstractInterpreter()

Method Summary

void	configure(Configuration config)
void	contextualize(Context aContext)
void	dispose()
void	forwardTo(String uri, Object bizData, org.apache.cocoon.components.flow.WebContinuation continuation, org.apache.cocoon.environment.Redirector redirector)
String	getInterpreterID() Get the unique ID for this interpreter, which can be used to distinguish user value scopes attached to the session.
String	getScriptExtension()
void	register(String source) Registers a source file with the interpreter.
void	service(ServiceManager sm)
void	setInterpreterID(String interpreterID) Set the unique ID for this interpreter, which can be used to distinguish user value scopes attached to the session.

Methods inherited from class org.apache.cocoon.util.AbstractLogEnabled

getLogger, setLogger

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.cocoon.components.flow.Interpreter

callFunction, handleContinuation

Field Detail

avalonContext

protected Context avalonContext

needResolve

protected ArrayList needResolve

List of source locations that need to be resolved.

manager

protected ServiceManager manager

continuationsMgr

protected org.apache.cocoon.components.flow.ContinuationsManager continuationsMgr

processInfoProvider

protected org.apache.cocoon.processing.ProcessInfoProvider processInfoProvider

newObjectModel

protected org.apache.cocoon.el.objectmodel.ObjectModel newObjectModel

settings

protected org.apache.cocoon.configuration.Settings settings

The settings of Cocoon.

reloadScripts

protected boolean reloadScripts

Whether reloading of scripts should be done. Specified through the "reload-scripts" attribute in flow.xmap.

checkTime

protected long checkTime

Interval between two checks for modified script files. Specified through the "check-time" XML attribute in flow.xmap.

Constructor Detail

AbstractInterpreter

public AbstractInterpreter()

Method Detail

setInterpreterID

public void setInterpreterID(String interpreterID)

Set the unique ID for this interpreter, which can be used to distinguish user value scopes attached to the session.

Specified by:

setInterpreterID in interface org.apache.cocoon.components.flow.Interpreter

getInterpreterID

public String getInterpreterID()

Get the unique ID for this interpreter, which can be used to distinguish user value scopes attached to the session.

Specified by:

getInterpreterID in interface org.apache.cocoon.components.flow.Interpreter

Returns:

a unique ID for this interpreter

configure

public void configure(Configuration config)
               throws ConfigurationException

Specified by:

configure in interface Configurable

Throws:

ConfigurationException

See Also:

Configurable.configure(org.apache.avalon.framework.configuration.Configuration)

service

public void service(ServiceManager sm)
             throws ServiceException

Specified by:

service in interface Serviceable

Throws:

ServiceException

See Also:

Serviceable.service(org.apache.avalon.framework.service.ServiceManager)

contextualize

public void contextualize(Context aContext)
                   throws ContextException

Specified by:

contextualize in interface Contextualizable

Throws:

ContextException

See Also:

Contextualizable.contextualize(org.apache.avalon.framework.context.Context)

dispose

public void dispose()

Specified by:

dispose in interface Disposable

See Also:

Disposable.dispose()

register

public void register(String source)

Registers a source file with the interpreter. Using this method an implementation keeps track of all the script files which are compiled. This allows them to reload the script files which get modified on the file system.

The parsing/compilation of a script file by an interpreter happens in two phases. In the first phase the file's location is registered in the needResolve array.

The second is possible only when a Cocoon Environment is passed to the Interpreter. This allows the file location to be resolved using Cocoon's SourceFactory class.

Once a file's location can be resolved, it is removed from the needResolve array and placed in the scripts hash table. The key in this hash table is the file location string, and the value is a DelayedRefreshSourceWrapper instance which keeps track of when the file needs to re-read.

Specified by:

register in interface org.apache.cocoon.components.flow.Interpreter

Parameters:

source - the location of the script

See Also:

Environment, DelayedRefreshSourceWrapper

forwardTo

public void forwardTo(String uri,
                      Object bizData,
                      org.apache.cocoon.components.flow.WebContinuation continuation,
                      org.apache.cocoon.environment.Redirector redirector)
               throws Exception

Specified by:

forwardTo in interface org.apache.cocoon.components.flow.Interpreter

Throws:

Exception

See Also:

Interpreter.forwardTo(java.lang.String, java.lang.Object, org.apache.cocoon.components.flow.WebContinuation, org.apache.cocoon.environment.Redirector)

getScriptExtension

public String getScriptExtension()

Specified by:

getScriptExtension in interface org.apache.cocoon.components.flow.Interpreter

See Also:

Interpreter.getScriptExtension()