All Packages  Class Hierarchy  This Package  Previous  Next  Index

Interface org.w3c.tools.resources.FilterInterface

public interface FilterInterface

Method Index

 o exceptionFilter(RequestInterface, ProtocolException, FilterInterface[], int)
 o ingoingFilter(RequestInterface, FilterInterface[], int)
The filter's ingoing method is called before any request processing is done by the target resource.
 o lookup(LookupState, LookupResult)
The lookup stage filtering.
 o outgoingFilter(RequestInterface, ReplyInterface, FilterInterface[], int)
The filter's outgoing method is called once the target resource has computed a reply.
 o outputFilter(RequestInterface, ReplyInterface, OutputStream)

Methods

 o lookup
 public abstract boolean lookup(LookupState ls,
                                LookupResult lr) throws ProtocolException
The lookup stage filtering. This filter is invoked during lookup, it can cancel the lookup operation in progress, by either throwing an exception (in case of error), or by returning true, in which case, the filter has perform the whole lookup operation itself.

Parameters:
ls - The current lookup state, describing the state of the lookup operation in progress.
lr - The current lookup result, describing the already computed part of the lookup operation.
Returns:
A boolean, true if lookup has been completed by the filter, and nothing else need to be done to complete it. Otherwise lookup should continue normally, and the filter returns false.
Throws: ProtocolException
If some error occurs, and the whole lookup operation cannot be continued normally.
 o ingoingFilter
 public abstract ReplyInterface ingoingFilter(RequestInterface request,
                                              FilterInterface filters[],
                                              int fidx) throws ProtocolException
The filter's ingoing method is called before any request processing is done by the target resource.

This method can (if able) compute the whole request's reply, and return it. If processing should continue normally, then the filter must return null.

If a filter's ingoingFilter method gets called, then it is guaranteed that either its outgoingFilter method or its exceptionFilter method gets called.

Parameters:
request - The request being processed.
filters - The whole array of filters to be applied before actually continuing the process.
fidx - The index in the above array of the filter being called.
Returns:
A Reply instance, if the filter knows how to compute it, or null if the request processing should continue normally.
Throws: ProtocolException
If the filter fails.
 o outgoingFilter
 public abstract ReplyInterface outgoingFilter(RequestInterface request,
                                               ReplyInterface reply,
                                               FilterInterface filters[],
                                               int fidx) throws ProtocolException
The filter's outgoing method is called once the target resource has computed a reply.

This method can return a Reply instance, in which case, the processing should be aborted, and the returned reply should be emited back to the client. Otherwise, if the filter returns null the processing continues normally.

Parameters:
request - The request being processed.
reply - The original reply, as emited by the target resource, and which has already been processed by the first filters.
filters - The whole array of filters to be applied before actually continuing the process.
fidx - The index in the above array of the filter being called.
Throws: ProtocolException
If the filter fails.
 o exceptionFilter
 public abstract ReplyInterface exceptionFilter(RequestInterface request,
                                                ProtocolException ex,
                                                FilterInterface filters[],
                                                int fidx)
Parameters:
request - The request being processed.
ex - The exception that occured during processing the request. and which has already been processed by the first filters.
filters - The whole array of filters to be applied before actually continuing the process.
fidx - The index in the above array of the filter being called.
 o outputFilter
 public abstract OutputStream outputFilter(RequestInterface request,
                                           ReplyInterface reply,
                                           OutputStream output)

All Packages  Class Hierarchy  This Package  Previous  Next  Index