/* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.xmlbeans.impl.tool;
import org.w3.x2001.xmlSchema.SchemaDocument.Schema;
import org.w3.x2001.xmlSchema.ImportDocument.Import;
import org.w3.x2001.xmlSchema.IncludeDocument.Include;
import java.util.LinkedList;
import java.util.Set;
import java.util.HashSet;
import java.util.Arrays;
public abstract class SchemaImportResolver
{
/**
* Called when the ImportLoader wishes to resolve the
* given import. Should return a SchemaResource whose
* "equals" relationship reveals when a SchemaResource is
* duplicated and shouldn't be examined again.
*
* Returns null if the resource reference should be ignored.
*/
public abstract SchemaResource lookupResource(String nsURI, String URL);
/**
* Called to notify that the expected namespace is different from the
* actual namespace, or if no namespace is known, to report the
* discovered namespace.
*/
public abstract void reportActualNamespace(SchemaResource resource, String actualNamespace);
/**
* Used to supply a schema resource with an optional associated
* expected-namespace-URI and original-location-URL.
*
* The equals (and hashCode) implementations of the SchemaResource
* objects will be used to avoid examining the same resource twice;
* these must be implemented according to the desired rules for
* determining that two resources are the same.
*/
public interface SchemaResource
{
/**
* Returns a parsed schema object.
*/
public Schema getSchema();
public String getNamespace();
public String getSchemaLocation();
}
protected final void resolveImports(SchemaResource[] resources)
{
LinkedList queueOfResources = new LinkedList(Arrays.asList(resources));
LinkedList queueOfLocators = new LinkedList();
Set seenResources = new HashSet();
for (;;)
{
SchemaResource nextResource;
// fetch next resource.
if (!queueOfResources.isEmpty())
{
// either off the initial queue
nextResource = (SchemaResource)queueOfResources.removeFirst();
}
else if (!queueOfLocators.isEmpty())
{
// or off the list of locators
SchemaLocator locator = (SchemaLocator)queueOfLocators.removeFirst();
nextResource = lookupResource(locator.namespace, locator.schemaLocation);
if (nextResource == null)
continue;
}
else
{
// if no more, then terminate loop
break;
}
// track and skip duplicates
if (seenResources.contains(nextResource))
continue;
seenResources.add(nextResource);
// get resource contents
Schema schema = nextResource.getSchema();
if (schema == null)
continue;
// check actual namespace
String actualTargetNamespace = schema.getTargetNamespace();
if (actualTargetNamespace == null)
actualTargetNamespace = "";
// report actual namespace
String expectedTargetNamespace = nextResource.getNamespace();
if (expectedTargetNamespace == null ||
!actualTargetNamespace.equals(expectedTargetNamespace))
{
reportActualNamespace(nextResource, actualTargetNamespace);
}
// now go through and record all the imports
Import[] schemaImports = schema.getImportArray();
for (int i = 0; i < schemaImports.length; i++)
{
queueOfLocators.add(new SchemaLocator(schemaImports[i].getNamespace() == null ? "" : schemaImports[i].getNamespace(), schemaImports[i].getSchemaLocation()));
}
// and record all the includes too
Include[] schemaIncludes = schema.getIncludeArray();
for (int i = 0; i < schemaIncludes.length; i++)
{
queueOfLocators.add(new SchemaLocator(null, schemaIncludes[i].getSchemaLocation()));
}
}
}
private static class SchemaLocator
{
public SchemaLocator(String namespace, String schemaLocation)
{
this.namespace = namespace;
this.schemaLocation = schemaLocation;
}
public final String namespace;
public final String schemaLocation;
}
}