org.apache.catalina.core

Class ApplicationDispatcher

java.lang.Object

org.apache.catalina.core.ApplicationDispatcher

All Implemented Interfaces:

javax.servlet.RequestDispatcher

public final class ApplicationDispatcher
extends Object
implements javax.servlet.RequestDispatcher

Standard implementation of RequestDispatcher that allows a request to be forwarded to a different resource to create the ultimate response, or to include the output of another resource in the response from this resource. This implementation allows application level servlets to wrap the request and/or response objects that are passed on to the called resource, as long as the wrapping classes extend javax.servlet.ServletRequestWrapper and javax.servlet.ServletResponseWrapper.

Version:

$Revision: 1.16 $ $Date: 2007/02/26 22:57:08 $

Author:

Craig R. McClanahan

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	ApplicationDispatcher.PrivilegedDispatch
protected class	ApplicationDispatcher.PrivilegedInclude

Field Summary

Fields

Modifier and Type	Field and Description
static String	LAST_DISPATCH_REQUEST_PATH_ATTR

Fields inherited from interface javax.servlet.RequestDispatcher

ERROR_EXCEPTION, ERROR_EXCEPTION_TYPE, ERROR_MESSAGE, ERROR_REQUEST_URI, ERROR_SERVLET_NAME, ERROR_STATUS_CODE, FORWARD_CONTEXT_PATH, FORWARD_MAPPING, FORWARD_PATH_INFO, FORWARD_QUERY_STRING, FORWARD_REQUEST_URI, FORWARD_SERVLET_PATH, INCLUDE_CONTEXT_PATH, INCLUDE_MAPPING, INCLUDE_PATH_INFO, INCLUDE_QUERY_STRING, INCLUDE_REQUEST_URI, INCLUDE_SERVLET_PATH

Constructor Summary

Constructors

Constructor and Description
ApplicationDispatcher(Wrapper wrapper, javax.servlet.http.HttpServletMapping mappingForDispatch, String requestURI, String servletPath, String pathInfo, String queryString, String name) Construct a new instance of this class, configured according to the specified parameters.

Method Summary

Modifier and Type	Method and Description
void	dispatch(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response, javax.servlet.DispatcherType dispatcherType) Dispatches the given request and response to the resource for which this dispatcher was acquired.
void	forward(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response) Forwards the given request and response to the resource for which this dispatcher was acquired.
String	getInfo() Return the descriptive information about this implementation.
void	include(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response) Include the response from another resource in the current response.

Methods inherited from class java.lang.Object

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

Field Detail

LAST_DISPATCH_REQUEST_PATH_ATTR

public static final String LAST_DISPATCH_REQUEST_PATH_ATTR

See Also:

Constant Field Values

Constructor Detail

ApplicationDispatcher

public ApplicationDispatcher(Wrapper wrapper,
                             javax.servlet.http.HttpServletMapping mappingForDispatch,
                             String requestURI,
                             String servletPath,
                             String pathInfo,
                             String queryString,
                             String name)

Construct a new instance of this class, configured according to the specified parameters. If both servletPath and pathInfo are null, it will be assumed that this RequestDispatcher was acquired by name, rather than by path.

Parameters:

wrapper - The Wrapper associated with the resource that will be forwarded to or included (required)

requestURI - The request URI to this resource (if any)

servletPath - The revised servlet path to this resource (if any)

pathInfo - The revised extra path information to this resource (if any)

queryString - Query string parameters included with this request (if any)

name - Servlet name (if a named dispatcher was created) else null

Method Detail

getInfo

public String getInfo()

Return the descriptive information about this implementation.

forward

public void forward(javax.servlet.ServletRequest request,
                    javax.servlet.ServletResponse response)
             throws javax.servlet.ServletException,
                    IOException

Forwards the given request and response to the resource for which this dispatcher was acquired.

Any runtime exceptions, IOException, or ServletException thrown by the target will be propagated to the caller.

Specified by:

forward in interface javax.servlet.RequestDispatcher

Parameters:

request - The request to be forwarded

response - The response to be forwarded

Throws:

IOException - if an input/output error occurs

javax.servlet.ServletException - if a servlet exception occurs

dispatch

public void dispatch(javax.servlet.ServletRequest request,
                     javax.servlet.ServletResponse response,
                     javax.servlet.DispatcherType dispatcherType)
              throws javax.servlet.ServletException,
                     IOException

Dispatches the given request and response to the resource for which this dispatcher was acquired.

Any runtime exceptions, IOException, or ServletException thrown by the target will be propagated to the caller.

Parameters:

request - The request to be forwarded

response - The response to be forwarded

dispatcherType - The type of dispatch to be performed

Throws:

IOException - if an input/output error occurs

javax.servlet.ServletException - if a servlet exception occurs

IllegalArgumentException - if the dispatcher type is different from FORWARD, ERROR, and ASYNC

include

public void include(javax.servlet.ServletRequest request,
                    javax.servlet.ServletResponse response)
             throws javax.servlet.ServletException,
                    IOException

Include the response from another resource in the current response. Any runtime exception, IOException, or ServletException thrown by the called servlet will be propagated to the caller.

Specified by:

include in interface javax.servlet.RequestDispatcher

Parameters:

request - The servlet request that is including this one

response - The servlet response to be appended to

Throws:

IOException - if an input/output error occurs

javax.servlet.ServletException - if a servlet exception occurs