edu.ucsb.adl.middleware
Class IdentifiersServlet

java.lang.Object
  |
  +--javax.servlet.GenericServlet
        |
        +--javax.servlet.http.HttpServlet
              |
              +--edu.ucsb.adl.middleware.IdentifiersServlet

All Implemented Interfaces:

java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public final class IdentifiersServlet

extends javax.servlet.http.HttpServlet

HTTP interface to the ADL identifiers service. The identifiers service can be accessed by an HTTP GET request containing one URL-encoded parameter: collection, the name of a collection. If the URL of this servlet is S, then an example of a complete URL might be:

S?collection=adl_catalog

The returned data has content type text/xml and uses UTF-8 encoding, and has the following structure:

<!DOCTYPE ADL-identifiers [
    <!ELEMENT ADL-identifiers (collection, id*)>
    <!ELEMENT collection (#PCDATA)>
    <!ELEMENT id (#PCDATA)>
]>

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/IdentifiersServlet.java,v 1.1 2006/06/22 20:47:15 gjanee Exp $

$Log: IdentifiersServlet.java,v $ Revision 1.1 2006/06/22 20:47:15 gjanee Initial revision

Author:

Greg Janée
Alexandria Digital Library

See Also:

Serialized Form

Constructor Summary

IdentifiersServlet()
Creates an IdentifiersServlet.

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 identifiers 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

IdentifiersServlet

public IdentifiersServlet()

Creates an IdentifiersServlet.

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 identifiers service. This method is multithread-safe.

Overrides:

doGet in class javax.servlet.http.HttpServlet

Parameters:

request - The HTTP request.

response - The HTTP response.

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