info.sswap.api.servlet
Class SimpleSSWAPServlet

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          info.sswap.api.servlet.AbstractSSWAPServlet
              info.sswap.api.servlet.SimpleSSWAPServlet

All Implemented Interfaces:

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

public abstract class SimpleSSWAPServlet
extends AbstractSSWAPServlet

A servlet wrapper that works in concert with MapsTo for the mapping of subjects to objects. Using a service class that is an extension of MapsTo allows developers to implement their service without the constraints and subtleties of servlet programming. This is best practice for most implementations. To use, extend and add a servlet launcher; e.g.:

 public class MyServlet extends SimpleSSWAPServlet {
     ...
 }
 

The servlet launcher MyServlet can be connected to the service class via either of two methods. Via web.xml; e.g.:

 <servlet>
 
  <servlet-name>MyServlet</servlet-name>
  <servlet-class>org.mySite.sswap.servlets.MyServlet</servlet-class>
 
  <init-param>
    <param-name>ServiceClass</param-name>
    <param-value>org.mySite.sswap.services.MyService</param-value>
  </init-param>
  
 </servlet>
 
 <servlet-mapping>
  <servlet-name>MyServlet</servlet-name>
  <url-pattern>/MyService/*</url-pattern>
 </servlet-mapping>
 
 

or, if ServiceClass is not defined in web.xml, the class may be specified by overriding getServiceClass. MyService must extend MapsTo to implement the service.

Author:

Damian Gessler

See Also:

MapsTo, Serialized Form

Field Summary

private static long

serialVersionUID

Fields inherited from class info.sswap.api.servlet.AbstractSSWAPServlet

remoteServiceURI, RRG_RETRIEVAL_SUFFIX

Constructor Summary

SimpleSSWAPServlet()

Method Summary

<T> java.lang.Class<T>	getServiceClass() Declare the class (e.g., MyService that performs the service.
protected void	handleRequest(RIG rig) This method is marked protected solely for package access purposes.
void	init(javax.servlet.ServletConfig servletConfig) Override this method (or GenericServlet.init() for custom servlet initialization code.
private MapsTo	newMapsTo(RIG rig) Dynamically instantiates a MapsTo object either first by name (from an init value in web.xml), or if that is not defined, by value (from getServiceClass).

Methods inherited from class info.sswap.api.servlet.AbstractSSWAPServlet

doGet, doPost, getTimeout, publishRRG, setTimeout

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

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

SimpleSSWAPServlet

public SimpleSSWAPServlet()

Method Detail

init

public void init(javax.servlet.ServletConfig servletConfig)
          throws javax.servlet.ServletException

Description copied from class: AbstractSSWAPServlet

Override this method (or GenericServlet.init() for custom servlet initialization code. If overriding this method, overriding method MUST call super.init(servletConfig) as the first line of code. This method is called once at the end of all internal initialization and before any requests are serviced.

The method is passed the Servlet Configuration and may throw a ServletException. Thrown errors are not caught and will terminate servlet initialization.

Uses for this method are to set the servlet timeout (see AbstractSSWAPServlet.setTimeout(int)), effect changes to URI caching (see SSWAP.getCache()), and so forth.

Specified by:

init in interface javax.servlet.Servlet

Overrides:

init in class AbstractSSWAPServlet

Parameters:

servletConfig - the ServletConfig object of the servlet

Throws:

javax.servlet.ServletException - on a servlet configuration error

See Also:

SSWAP, ServletConfig

getServiceClass

public <T> java.lang.Class<T> getServiceClass()

Declare the class (e.g., MyService that performs the service. The class must be a subclass of MapsTo. This can be done by overriding this method to return the class; e.g.:

 public <T> Class<T> getServiceClass() {
 return (Class<T>) MyService.class;
 }
 
 

A value in web.xml, if defined, will take precedence over this method.

Type Parameters:

T - subclass of MapsTo

Returns:

class to load for the service

See Also:

MapsTo

handleRequest

protected final void handleRequest(RIG rig)

This method is marked protected solely for package access purposes. It should not be called directly and cannot be overridden. The servlet handler will call this method automatically. To perform a specific subject -> object mapping, override MapsTo.mapsTo(info.sswap.api.model.SSWAPSubject).

Specified by:

handleRequest in class AbstractSSWAPServlet

Parameters:

rig - RIG invoking the service. This RIG should be edited and will become the basis for the RRG returned by the service. Best practice is to leave most of the RIG untouched, modifying only the SSWAPObject subgraphs.

See Also:

MapsTo

newMapsTo

private MapsTo newMapsTo(RIG rig)
                  throws java.lang.InstantiationException,
                         java.lang.IllegalAccessException,
                         java.lang.ClassNotFoundException

Dynamically instantiates a MapsTo object either first by name (from an init value in web.xml), or if that is not defined, by value (from getServiceClass).

Parameters:

rig - RIG for this request

Returns:

an instance of the service class

Throws:

java.lang.ClassNotFoundException

java.lang.IllegalAccessException

java.lang.InstantiationException