com.veriplace.web.servlet
Class AbstractVeriplaceServlet

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          com.veriplace.web.servlet.AbstractVeriplaceServlet

All Implemented Interfaces:

java.io.Serializable, Servlet, ServletConfig

public abstract class AbstractVeriplaceServlet
extends HttpServlet

Base class for servlets that use Veriplace APIs.

Deriving from this class allows you to access Veriplace user/location data as follows:

• When the servlet starts up, it initializes a Veriplace instance or retrieves an existing one, using VeriplaceServletHelper.getSharedVeriplaceInstance(javax.servlet.ServletContext) (see VeriplaceServletHelper for configuration parameters).
• For each servlet request, if your class has a UsesVeriplace annotation specifying a need for user or location data, the corresponding Veriplace requests are done before your servlet handler executes. This may include redirects and callbacks, which happen transparently.
• The base class provides your request handler with a VeriplaceState object which you can use to get the user/location properties, or to perform other operations.

You may attach the following init-params to your servlet in web.xml:

• veriplace.views: The name for a set of parameters in web.xml specifying how Veriplace should display status or error pages for this servlet. If the name is "myParams", the corresponding context-params will have names starting with "veriplace.views.myParams.". See VeriplaceServletHelper.getViewRendererFromViewParams(javax.servlet.ServletContext, String).
• veriplace.defaultview: Optional name of a view that this class's default implementation of doRequestInternal(HttpServletRequest, HttpServletResponse, VeriplaceState) will display. This is an easy way to define a servlet that does some simple preprocessing of a request and then forwards to a JSP. The view name prefix and suffix specified in your view parameters are also applied to this view name, so by default there is an implied ".jsp" extension.

See Also:

Serialized Form

Field Summary

protected java.lang.String	defaultViewName
protected Veriplace	veriplace

Constructor Summary

AbstractVeriplaceServlet()

Method Summary

protected void	doGet(HttpServletRequest request, HttpServletResponse response)
protected void	doGetOrPost(HttpServletRequest request, HttpServletResponse response)
protected void	doPost(HttpServletRequest request, HttpServletResponse response)
protected void	doRequestInternal(HttpServletRequest request, HttpServletResponse response, VeriplaceState veriplaceState) Override this method to implement your request handler.
protected void	doRequestInternal(HttpServletRequest request, HttpServletResponse response, Veriplace veriplace, VeriplaceState veriplaceState) Override this method to implement your request handler.
protected java.util.Properties	getProperties() Returns the contents of the properties file specified in the "veriplace.properties-file" servlet context parameter in web.xml.
protected Client	getVeriplaceClient(HttpServletRequest request, Veriplace defaultInstance) Override this method if you might need to use a different Veriplace Client for some requests.
void	init(ServletConfig config) Initialize the client.
protected void	setupVeriplaceState(HttpServletRequest request, VeriplaceState state) Override this method if you need to change any properties of the VeriplaceState, such as VeriplaceState.setLocationMode(String), based on properties of the current request.

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doOptions, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet

destroy, 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

Field Detail

veriplace

protected Veriplace veriplace

defaultViewName

protected java.lang.String defaultViewName

Constructor Detail

AbstractVeriplaceServlet

public AbstractVeriplaceServlet()

Method Detail

init

public void init(ServletConfig config)
          throws ServletException

Initialize the client.

Specified by:

init in interface Servlet

Overrides:

init in class GenericServlet

Throws:

ServletException

doGet

protected void doGet(HttpServletRequest request,
                     HttpServletResponse response)
              throws ServletException,
                     java.io.IOException

Overrides:

doGet in class HttpServlet

Throws:

ServletException

java.io.IOException

doPost

protected void doPost(HttpServletRequest request,
                      HttpServletResponse response)
               throws ServletException,
                      java.io.IOException

Overrides:

doPost in class HttpServlet

Throws:

ServletException

java.io.IOException

doGetOrPost

protected void doGetOrPost(HttpServletRequest request,
                           HttpServletResponse response)
                    throws ServletException,
                           java.io.IOException

Throws:

ServletException

java.io.IOException

doRequestInternal

protected void doRequestInternal(HttpServletRequest request,
                                 HttpServletResponse response,
                                 VeriplaceState veriplaceState)
                          throws java.io.IOException,
                                 ServletException,
                                 VeriplaceException

Override this method to implement your request handler.

This method will be called for both GET and POST requests. If you need to distinguish between GET and POST, check the properties of the HttpServletRequest; however, be aware that an operation that starts out as a POST may come back as a GET, if you went through a redirect/callback process for location discovery.

The base class implementation of this method simply forwards the request to the page specified in init-params as veriplace.defaultview.

Throws:

java.io.IOException

ServletException

VeriplaceException

doRequestInternal

protected void doRequestInternal(HttpServletRequest request,
                                 HttpServletResponse response,
                                 Veriplace veriplace,
                                 VeriplaceState veriplaceState)
                          throws java.io.IOException,
                                 ServletException,
                                 VeriplaceException

Override this method to implement your request handler. This version provides the current Veriplace instance as a convenience.

This method will be called for both GET and POST requests. If you need to distinguish between GET and POST, check the properties of the HttpServletRequest; however, be aware that an operation that starts out as a POST may come back as a GET, if you went through a redirect/callback process for location discovery.

The base class implementation of this method simply forwards the request to the page specified in init-params as veriplace.defaultview.

Throws:

java.io.IOException

ServletException

VeriplaceException

getVeriplaceClient

protected Client getVeriplaceClient(HttpServletRequest request,
                                    Veriplace defaultInstance)
                             throws ConfigurationException,
                                    UnexpectedException

Override this method if you might need to use a different Veriplace Client for some requests. For instance, you might use the same servlet to handling requests for more than one Veriplace application, each with its own consumer key and token. A Client is a fairly lightweight object, so it's acceptable to create a new one for each request if you want to.

Throws:

ConfigurationException

UnexpectedException

setupVeriplaceState

protected void setupVeriplaceState(HttpServletRequest request,
                                   VeriplaceState state)
                            throws VeriplaceException

Override this method if you need to change any properties of the VeriplaceState, such as VeriplaceState.setLocationMode(String), based on properties of the current request.

Throws:

VeriplaceException

getProperties

protected java.util.Properties getProperties()
                                      throws ConfigurationException

Returns the contents of the properties file specified in the "veriplace.properties-file" servlet context parameter in web.xml. This allows you to access non-Veriplace-related properties that you may wish to have in the same file for convenience.

Throws:

ConfigurationException - if the properties file was not specified or can't be read