com.ibm.aglets
Class AgletContextImpl

java.lang.Object
  |
  +--com.ibm.aglets.AgletContextImpl

All Implemented Interfaces:

AgletContext

public final class AgletContextImpl

extends java.lang.Object

implements AgletContext

The AgletContextImpl class is the execution context for running aglets. It provides means for maintaining and managing running aglets in an environment where the aglets are protected from each other and the host system is secured against malicious aglets.

Version:

1.20 $Date: 2001/07/28 06:31:54 $

Author:

Danny B. Lange, Mitsuru Oshima, ONO Kouichi

Method Summary

void	addContextListener(ContextListener o) Adds the specified context listener to receive context events from this context.
void	clearCache(java.net.URL codebase) Clear the cache
AgletProxy	createAglet(java.net.URL url, java.lang.String classname, java.lang.Object init) Creates an instance of the specified aglet located at the specified URL.
java.util.Enumeration	getAgletProxies() Gets the aglet proxies in the current execution context.
java.util.Enumeration	getAgletProxies(int type) Gets the aglet proxies in the current execution context.
AgletProxy	getAgletProxy(AgletID aid) Gets the proxy for an aglet specified by its identity.
AgletProxy	getAgletProxy(java.net.URL host, AgletID aid) Deprecated.
java.applet.AudioClip	getAudioClip(java.net.URL url) Gets an audio clip.
java.net.URL	getHostingURL() Returns the URL of the daemon serving all current execution contexts.
java.awt.Image	getImage(ImageData d) Gets an image.
java.awt.Image	getImage(java.net.URL url) Gets an image.
ImageData	getImageData(java.net.URL url) Gets an image data.
java.lang.String	getName() Gets the name of the context
Persistence	getPersistence()
java.lang.Object	getProperty(java.lang.String key) Gets the context property indicated by the key.
java.lang.Object	getProperty(java.lang.String key, java.lang.Object def) Gets the context property indicated by the key and default value.
ResourceManagerFactory	getResourceManagerFactory()
ReplySet	multicastMessage(Message msg) Sends a multicast message to the subscribers in the context.
void	postEvent(ContextEvent event, boolean sync)
void	postEvent0(ContextEvent event)
void	receiveAglet(Name agent_name, ClassName[] classnames, java.lang.String codebase, byte[] agent, java.lang.String sender) Receives an aglet.
void	removeContextListener(ContextListener o) Removes the specified context listener.
AgletProxy	retractAglet(Ticket ticket, AgletID aid)
AgletProxy	retractAglet(java.net.URL url) Deprecated.
AgletProxy	retractAglet(java.net.URL url, AgletID aid) Retracts the Aglet specified by its url: scheme://host-domain-name/[user-name]#aglet-identity.
void	setPersistence(Persistence p)
void	setProperty(java.lang.String key, java.lang.Object value) Sets the context property
void	setResourceManagerFactory(ResourceManagerFactory rmf)
void	showDocument(java.net.URL url) Shows a new document.
void	shutdown() Shutdown the context.
void	shutdown(Message msg) Shutdown the context with the specific message object.
void	start() Starts
void	start(boolean reactivate) Starts the context.

Methods inherited from class java.lang.Object

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

Method Detail

addContextListener

public void addContextListener(ContextListener o)

Description copied from interface: AgletContext

Adds the specified context listener to receive context events from this context.

Specified by:

addContextListener in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

listener - the context listener

Throws:

java.lang.SecurityException -

clearCache

public void clearCache(java.net.URL codebase)

Clear the cache

Specified by:

clearCache in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

codebase - the codebase of the cache to clean up. if null, entire cache in this context is cleared.

createAglet

public AgletProxy createAglet(java.net.URL url,
                              java.lang.String classname,
                              java.lang.Object init)
                       throws java.io.IOException,
                              AgletException,
                              java.lang.ClassNotFoundException,
                              java.lang.InstantiationException

Creates an instance of the specified aglet located at the specified URL.

Specified by:

createAglet in interface AgletContext

Parameters:

url - the URL to load the aglet class from.

name - the aglet's class name.

Returns:

a newly instantiated and initialized Aglet.

Throws:

java.lang.ClassNotFoundException - if the class was not found

java.lang.InstantiationException - if failed to instantiate the Aglet.

getAgletProxies

public java.util.Enumeration getAgletProxies()

Gets the aglet proxies in the current execution context.

Specified by:

getAgletProxies in interface AgletContext

Returns:

an enumeration of aglet proxies.

getAgletProxies

public java.util.Enumeration getAgletProxies(int type)

Gets the aglet proxies in the current execution context.

Specified by:

getAgletProxies in interface AgletContext

Returns:

an enumeration of aglet proxies.

getAgletProxy

public AgletProxy getAgletProxy(AgletID aid)

Gets the proxy for an aglet specified by its identity.

Specified by:

getAgletProxy in interface AgletContext

Parameters:

aid - the identity of the aglet.

Returns:

the aglet proxy.

getAgletProxy

public AgletProxy getAgletProxy(java.net.URL host,
                                AgletID aid)

Deprecated.

Gets the proxy for a remote aglet specified by url

Specified by:

getAgletProxy in interface AgletContext

Parameters:

aid - the identity of the aglet.

Returns:

the aglet proxy

getAudioClip

public java.applet.AudioClip getAudioClip(java.net.URL url)

Description copied from interface: AgletContext

Gets an audio clip.

Specified by:

getAudioClip in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

audio - an absolute URL giving the location of the audio file.

Returns:

the Audio clip object give by the URL.

getHostingURL

public java.net.URL getHostingURL()

Returns the URL of the daemon serving all current execution contexts.

Specified by:

getHostingURL in interface AgletContext

Throws:

AgletException - if the hosting URL cannot be determined.

getImage

public java.awt.Image getImage(ImageData d)

Description copied from interface: AgletContext

Gets an image. This is a tempolary solution.

Specified by:

getImage in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

image - a serializable image data.

Returns:

the image object converted from the image data.

getImage

public java.awt.Image getImage(java.net.URL url)

Description copied from interface: AgletContext

Gets an image.

Specified by:

getImage in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

image - an absolute URL giving the location of the image file.

Returns:

the image object give by the URL.

getImageData

public ImageData getImageData(java.net.URL url)

Description copied from interface: AgletContext

Gets an image data. This is a tempolary solution.

Specified by:

getImageData in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

image - an absolute URL giving the location of the image file.

Returns:

the serializable image data.

getName

public java.lang.String getName()

Gets the name of the context

Specified by:

getName in interface AgletContext

Returns:

the name of the context

getPersistence

public Persistence getPersistence()
                           throws java.io.IOException

getProperty

public java.lang.Object getProperty(java.lang.String key)

Gets the context property indicated by the key.

Specified by:

getProperty in interface AgletContext

Parameters:

key - the name of the context property.

Returns:

the value of the specified key.

getProperty

public java.lang.Object getProperty(java.lang.String key,
                                    java.lang.Object def)

Gets the context property indicated by the key and default value.

Specified by:

getProperty in interface AgletContext

Parameters:

key - the name of the context property.

def - the value to use if this property is not set.

Returns:

the value of the specified key.

getResourceManagerFactory

public ResourceManagerFactory getResourceManagerFactory()

multicastMessage

public ReplySet multicastMessage(Message msg)

Description copied from interface: AgletContext

Sends a multicast message to the subscribers in the context.

Specified by:

multicastMessage in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

message - to send

Returns:

ReplySet containing FutureReplies

postEvent

public void postEvent(ContextEvent event,
                      boolean sync)

postEvent0

public void postEvent0(ContextEvent event)

receiveAglet

public void receiveAglet(Name agent_name,
                         ClassName[] classnames,
                         java.lang.String codebase,
                         byte[] agent,
                         java.lang.String sender)
                  throws AgletException,
                         java.lang.ClassNotFoundException

Receives an aglet. Will start the aglet and return its proxy.

Parameters:

aglet - the aglet to be received by the context.

Throws:

AgletException - if it is not received.

removeContextListener

public void removeContextListener(ContextListener o)

Description copied from interface: AgletContext

Removes the specified context listener.

Specified by:

removeContextListener in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

listener - the context listener

Throws:

java.lang.SecurityException -

retractAglet

public AgletProxy retractAglet(Ticket ticket,
                               AgletID aid)
                        throws java.io.IOException,
                               AgletException

retractAglet

public AgletProxy retractAglet(java.net.URL url)
                        throws java.io.IOException,
                               AgletException

Deprecated.

Retracts the Aglet specified by its url: scheme://host-domain-name/[user-name]#aglet-identity.

Specified by:

retractAglet in interface AgletContext

Parameters:

url - the location and aglet identity of the aglet to be retracted.

Returns:

the aglet proxy for the retracted aglet.

Throws:

AgletException - when the method failed to retract the aglet.

retractAglet

public AgletProxy retractAglet(java.net.URL url,
                               AgletID aid)
                        throws java.io.IOException,
                               AgletException

Retracts the Aglet specified by its url: scheme://host-domain-name/[user-name]#aglet-identity.

Specified by:

retractAglet in interface AgletContext

Parameters:

url - the location and aglet identity of the aglet to be retracted.

aid - the aglet identity of the aglet to be retracted.

Returns:

the aglet proxy for the retracted aglet.

Throws:

AgletException - when the method failed to retract the aglet.

setPersistence

public void setPersistence(Persistence p)
                    throws AgletException

setProperty

public void setProperty(java.lang.String key,
                        java.lang.Object value)

Sets the context property

Specified by:

setProperty in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

key - the name of the context property.

value - the value to be stored.

Returns:

the value of the specified key.

setResourceManagerFactory

public void setResourceManagerFactory(ResourceManagerFactory rmf)

showDocument

public void showDocument(java.net.URL url)

Shows a new document. This may be ignored by the aglet context. ContextPermission("showDocument", url) is required.

Specified by:

showDocument in interface AgletContext

Parameters:

url - an url to be shown

shutdown

public void shutdown()

Description copied from interface: AgletContext

Shutdown the context. This is ignored if the context is already stopped.

Specified by:

shutdown in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Throws:

java.lang.SecurityException - if the current execution context is not allowd to shutdown

See Also:

start

shutdown

public void shutdown(Message msg)

Description copied from interface: AgletContext

Shutdown the context with the specific message object. This message object is delivered to all aglets in the context before all aglets are killed. This is ignored if the context is already stopped.

Specified by:

shutdown in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Throws:

java.lang.SecurityException - if the current execution context is not allowd to shutdown

See Also:

start

start

public void start()

Starts

Specified by:

start in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Throws:

java.lang.SecurityException -

start

public void start(boolean reactivate)

Description copied from interface: AgletContext

Starts the context. This is ignored if the context is already runnig.

Specified by:

start in interface AgletContext

Following copied from interface: com.ibm.aglet.AgletContext

Parameters:

reactivate - if false, it does not activate aglets in the deactivation spool

Throws:

java.lang.SecurityException -