org.ptolemy.ptango.lib

Class WebServerManager

java.lang.Object

org.ptolemy.ptango.lib.WebServerManager

public final class WebServerManager
extends java.lang.Object

A manager for creating and managing instances of a Jetty web server. Models with the WebServer attribute use this manager to register, start, and stop web applications while checking for conflicts with other web applications. This manager creates and starts up new web servers, one server per unique port, and shuts down web servers when no more models are using them.

Since:

Ptolemy II 10.0

Version:

$Id: WebServerManager.java 70402 2014-10-23 00:52:20Z cxh $

Author:

Elizabeth Latronico and Edward A. Lee

Accepted Rating:

Red (ltrnc)

Proposed Rating:

Red (ltrnc)

Method Summary

Modifier and Type	Method and Description
static WebServerManager	getInstance() Return the existing web server manager; create and return a new one if none is present yet.
boolean	isRegistered(java.lang.String fullModelName, int portNumber) Return true if the given application is registered with the server associated with the given port; false otherwise.
boolean	isRunning(java.lang.String fullModelName, int portNumber) Return true if the given application is registered with the server associated with the given port and this server is running; false otherwise.
int	register(WebApplicationInfo appInfo, int portNumber, boolean dynamicPortSelection) Register the following application with the manager.
void	unregister(WebApplicationInfo appInfo, int portNumber) Unregister the following application with the manager.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static WebServerManager getInstance()

Return the existing web server manager; create and return a new one if none is present yet.

Returns:

The web server manager

isRegistered

public boolean isRegistered(java.lang.String fullModelName,
                            int portNumber)

Return true if the given application is registered with the server associated with the given port; false otherwise. The model name is used to identify the application - only one instance of a model may be registered to a server. (Note that multiple instances of a model are possible by different servers on different ports.)

Parameters:

fullModelName - The full name of the model

portNumber - The port this application would be hosted on

Returns:

true if the given application is registered with the server associated with the given port; false otherwise.

isRunning

public boolean isRunning(java.lang.String fullModelName,
                         int portNumber)

Return true if the given application is registered with the server associated with the given port and this server is running; false otherwise. The model name is used to identify the application - only one instance of a model may be registered to a server. (Note that multiple instances of a model are possible by different servers on different ports.)

Parameters:

fullModelName - The full name of the model

portNumber - The port this application would be hosted on

Returns:

true if the given application is registered with the server associated with the given port and this server is running; false otherwise.

register

public int register(WebApplicationInfo appInfo,
                    int portNumber,
                    boolean dynamicPortSelection)
             throws java.lang.Exception

Register the following application with the manager. Check if the model in appInfo is already associated with a server. If not, assign the web application to the server, checking for conflicts with existing applications, creating new handlers where appropriate and pausing and restarting the server if necessary. Returns true if the application was successfully registered; false otherwise.

Parameters:

appInfo - Information about the registered web application

dynamicPortSelection - True if server may dynamically select a port; false if the server should use the fixed port and throw an exception if not available

portNumber - The desired port number to host this web application on

dynamicPortSelection - If true, then select the port dynamically.

Returns:

The actual port number the web application is running on (may be different from the portNumber parameter if dynamic selection is enabled)

Throws:

java.lang.Exception - thrown if web server cannot be instantiated or if application conflicts with an already-registered application

unregister

public void unregister(WebApplicationInfo appInfo,
                       int portNumber)
                throws java.lang.Exception

Unregister the following application with the manager. Remove all context handlers specific to this application and stop the web server if this is the only application running on it. Providing a port number allows other instances of the application on other ports to continue running.

Parameters:

appInfo - Information about the unregistered web application

portNumber - The port number that this application is running on

Throws:

java.lang.Exception - if there is no server associated with this port, the application is not running on the server associated with this port, or the application cannot be stopped.