com.day.cq.commons.servlets
Class AbstractCommandServlet

java.lang.Object
  javax.servlet.GenericServlet
      org.apache.sling.api.servlets.SlingSafeMethodsServlet
          org.apache.sling.api.servlets.SlingAllMethodsServlet
              com.day.cq.commons.servlets.AbstractPredicateServlet
                  com.day.cq.commons.servlets.AbstractCommandServlet

All Implemented Interfaces:

Serializable, Servlet, ServletConfig

Direct Known Subclasses:

TagCommandServlet

public abstract class AbstractCommandServlet
extends AbstractPredicateServlet

Abstract servlet to use for the client/server command interface. Note: due to a problem in SCR plugin, this class cannot extend from the AbstractPredicateServlet because the predicate provider reference would be double defined.

See Also:

Serialized Form

Field Summary

static String	ACTION_PARAM default action parameter name
static String	PATH_PARAM default path parameter name

Fields inherited from class com.day.cq.commons.servlets.AbstractPredicateServlet

FILTER_PARAM, PREDICATE_PARAM

Constructor Summary

AbstractCommandServlet()

Method Summary

protected void	doGet(SlingHttpServletRequest request, SlingHttpServletResponse response) Called by the SlingSafeMethodsServlet.mayService(SlingHttpServletRequest, SlingHttpServletResponse) method to handle an HTTP GET request.
protected void	doPost(SlingHttpServletRequest request, SlingHttpServletResponse response) Called by the SlingAllMethodsServlet.mayService(SlingHttpServletRequest, SlingHttpServletResponse) method to handle an HTTP POST request.
protected boolean	hasCommand(SlingHttpServletRequest request) Checks if the command in the request is supported.
protected abstract void	performCommand(SlingHttpServletRequest request, SlingHttpServletResponse response) Perform the command of the current request.
protected String	requireParameter(SlingHttpServletRequest request, String name) Get value of specified parameter, trim and verify that it's provided

Methods inherited from class com.day.cq.commons.servlets.AbstractPredicateServlet

doGet, getPredicate, selectorPredicateStart

Methods inherited from class org.apache.sling.api.servlets.SlingAllMethodsServlet

doDelete, doPut, getAllowedRequestMethods, isMethodValid, mayService

Methods inherited from class org.apache.sling.api.servlets.SlingSafeMethodsServlet

doGeneric, doHead, doOptions, doTrace, getServletInfo, handleMethodNotImplemented, service, service

Methods inherited from class javax.servlet.GenericServlet

destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, init, init, log, log

Methods inherited from class java.lang.Object

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

Field Detail

PATH_PARAM

public static final String PATH_PARAM

default path parameter name

See Also:

Constant Field Values

ACTION_PARAM

public static final String ACTION_PARAM

default action parameter name

See Also:

Constant Field Values

Constructor Detail

AbstractCommandServlet

public AbstractCommandServlet()

Method Detail

doPost

protected void doPost(SlingHttpServletRequest request,
                      SlingHttpServletResponse response)
               throws ServletException,
                      IOException

Description copied from class: SlingAllMethodsServlet

Called by the SlingAllMethodsServlet.mayService(SlingHttpServletRequest, SlingHttpServletResponse) method to handle an HTTP POST request.

This default implementation reports back to the client that the method is not supported.

Implementations of this class should overwrite this method with their implementation for the HTTP POST method support.

Overrides:

doPost in class SlingAllMethodsServlet

Parameters:

request - The HTTP request

response - The HTTP response

Throws:

ServletException - Not thrown by this implementation.

IOException - If the error status cannot be reported back to the client.

doGet

protected void doGet(SlingHttpServletRequest request,
                     SlingHttpServletResponse response)
              throws ServletException,
                     IOException

Description copied from class: AbstractPredicateServlet

Called by the SlingSafeMethodsServlet.mayService(SlingHttpServletRequest, SlingHttpServletResponse) method to handle an HTTP GET request.

This default implementation reports back to the client that the method is not supported.

Implementations of this class should overwrite this method with their implementation for the HTTP GET method support. Calls AbstractPredicateServlet.doGet(SlingHttpServletRequest, SlingHttpServletResponse, Predicate).

Overrides:

doGet in class AbstractPredicateServlet

Parameters:

request - The HTTP request

response - The HTTP response

Throws:

ServletException - Not thrown by this implementation.

IOException - If the error status cannot be reported back to the client.

hasCommand

protected boolean hasCommand(SlingHttpServletRequest request)
                      throws ServletException

Checks if the command in the request is supported. Returns false by default.

Parameters:

request - servlet request

Returns:

true if the command is supported.

Throws:

ServletException - if a servlet error occurs

performCommand

protected abstract void performCommand(SlingHttpServletRequest request,
                                       SlingHttpServletResponse response)
                                throws ServletException,
                                       IOException

Perform the command of the current request. This method is invoked if hasCommand(SlingHttpServletRequest) returns true for a POST request.

Parameters:

request - servlet request

response - servlet response

Throws:

ServletException - if an error occurs.

IOException - if an I/O error occurs.

requireParameter

protected String requireParameter(SlingHttpServletRequest request,
                                  String name)
                           throws ServletException

Get value of specified parameter, trim and verify that it's provided

Parameters:

request - the servlet request

name - the name of the parameter

Returns:

the value of the parameter

Throws:

ServletException - if the parameter is missing or empty.