edu.ucsb.adl.middleware
Class StatusServlet

java.lang.Object
  |
  +--javax.servlet.GenericServlet
        |
        +--javax.servlet.http.HttpServlet
              |
              +--edu.ucsb.adl.middleware.StatusServlet
All Implemented Interfaces:
java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public final class StatusServlet
extends javax.servlet.http.HttpServlet

HTTP interface to the ADL status service. The status service can be accessed by a simple HTTP GET request.

Service exceptions are caught and returned as HTTP errors. In particular, BadRequestException is mapped to 400 (bad request), NoAuthorizationException is mapped to 403 (forbidden), and InternalErrorException is mapped to 500 (internal server error).

Version:
$Header: /export/home/gjanee/middleware/edu/ucsb/adl/middleware/RCS/StatusServlet.java,v 1.5 2004/03/02 22:01:48 gjanee Exp $

$Log: StatusServlet.java,v $ Revision 1.5 2004/03/02 22:01:48 gjanee
If the middleware_configuration_file servlet initialization parameter is not available, we now look for it as a context-wide initialization parameter.

Revision 1.4 2001/11/16 17:41:33 gjanee
Internationalization support. All returned data now uses UTF-8 encoding.

Revision 1.3 2001/10/04 18:31:26 gjanee
To support the middleware being a web application, we now allow the location of the middleware configuration file to be specified relative to the web application directory.

Revision 1.2 2001/02/15 18:36:46 gjanee
Minor upgrade to servlet API 2.2.

Revision 1.1 2000/01/26 06:21:56 gjanee
Initial revision

Author:
Greg Janée
Alexandria Digital Library
See Also:
Serialized Form

Constructor Summary
StatusServlet()
          Creates a StatusServlet.
 
Method Summary
 void destroy()
          Frees all resources held by the servlet.
 void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
          HTTP GET interface to the ADL status service.
 void init(javax.servlet.ServletConfig config)
          Initializes the servlet.
 
Methods inherited from class javax.servlet.http.HttpServlet
doDelete, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service, service
 
Methods inherited from class javax.servlet.GenericServlet
getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

StatusServlet

public StatusServlet()
Creates a StatusServlet.

Method Detail

init

public void init(javax.servlet.ServletConfig config)
          throws javax.servlet.ServletException
Initializes the servlet.

Specified by:
init in interface javax.servlet.Servlet
Overrides:
init in class javax.servlet.GenericServlet
Parameters:
config - Must contain the following initialization parameter: middleware_configuration_file, the filename of the ADL middleware configuration file. If the filename is not absolute, it is interpreted relative to the middleware web application directory.
Throws:
javax.servlet.UnavailableException - If the initialization fails.
javax.servlet.ServletException

doGet

public void doGet(javax.servlet.http.HttpServletRequest request,
                  javax.servlet.http.HttpServletResponse response)
           throws java.io.IOException
HTTP GET interface to the ADL status service. This method is multithread-safe.

Overrides:
doGet in class javax.servlet.http.HttpServlet
Parameters:
request - The HTTP request.
response - The HTTP response, which is an HTML document.
Throws:
java.io.IOException - On any I/O error.

destroy

public void destroy()
Frees all resources held by the servlet.

Specified by:
destroy in interface javax.servlet.Servlet
Overrides:
destroy in class javax.servlet.GenericServlet