Package net.sf.saxon.lib

Interface ResourceResolver

All Known Implementing Classes:

CatalogResourceResolver, ChainedResourceResolver, DirectResourceResolver, ProtocolRestrictor.RestrictedResourceResolver, ResourceResolverDelegate, ResourceResolverWrappingLSResourceResolver, ResourceResolverWrappingURIResolver

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface ResourceResolver

Interface for processing a resource request to deliver a resource

It is a common feature of existing resolver APIs that they chain together. For example, it is often the case that when a new EntityResolver is added to an XMLReader, it is configured so that the existing (possibly underlying, implementation defined) resolver will be called if the newly specified resolver fails to resolve the URI. Two ResourceResolvers can be chained together into a single ResourceResolver by using the ChainedResourceResolver class.

The resolver methods in this class will generally return null if the requested resource could not be found. If instead the caller wants a failure to get the resource to be treated as an error, it is possible to request this by setting a property on the CatalogResourceResolver.

The usual mechanism for resolving a URI is to create a ResourceRequest, and pass it to a sequence of ResourceResolvers using the method ResourceRequest.resolve(net.sf.saxon.lib.ResourceResolver...). This will invoke each resolver in turn until one of them returns a non-null result.

Method Summary

Modifier and Type	Method	Description
javax.xml.transform.Source	resolve(ResourceRequest request)	Process a resource request to deliver a resource

Method Detail

resolve

javax.xml.transform.Source resolve(ResourceRequest request)
                            throws XPathException

Process a resource request to deliver a resource

Parameters:

request - the resource request

Returns:

the returned Source; or null to delegate resolution to another resolver. The type of Source must correspond to the type of resource requested: for non-XML resources, it should generally be a StreamSource.

Throws:

XPathException - if the request is invalid in some way, or if the identified resource is unsuitable, or if resolution is to fail rather than being delegated to another resolver.