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Tomcat example source code file (

This example Tomcat source code file ( is included in the "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Tomcat tags/keywords

digester, entityresolver, exception, hashmap, inputsource, inputsource, sax, saxexception, saxexception, schemaresolver, schemaresolver, string, string, util

The Tomcat source code

 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the License for the specific language governing permissions and
 * limitations under the License.
package org.apache.catalina.util;

import java.util.HashMap;

import org.apache.tomcat.util.digester.Digester;
import org.xml.sax.InputSource;
import org.xml.sax.EntityResolver;
import org.xml.sax.SAXException;

 * This class implements a local SAX's <code>EntityResolver. All
 * DTDs and schemas used to validate the web.xml file will re-directed
 * to a local file stored in the servlet-api.jar and jsp-api.jar.
 * @author Jean-Francois Arcand
public class SchemaResolver implements EntityResolver {

     * The disgester instance for which this class is the entity resolver.
    protected Digester digester;

     * The URLs of dtds and schemas that have been registered, keyed by the
     * public identifier that corresponds.
    protected HashMap entityValidator = new HashMap();

     * The public identifier of the DTD we are currently parsing under
     * (if any).
    protected String publicId = null;

     * Extension to make the difference between DTD and Schema.
    protected String schemaExtension = "xsd";

     * Create a new <code>EntityResolver that will redirect
     * all remote dtds and schema to a locat destination.
     * @param digester The digester instance.
    public SchemaResolver(Digester digester) {
        this.digester = digester;

     * Register the specified DTD/Schema URL for the specified public
     * identifier. This must be called before the first call to
     * <code>parse().
     * When adding a schema file (*.xsd), only the name of the file
     * will get added. If two schemas with the same name are added,
     * only the last one will be stored.
     * @param publicId Public identifier of the DTD to be resolved
     * @param entityURL The URL to use for reading this DTD
     public void register(String publicId, String entityURL) {
         String key = publicId;
         if (publicId.indexOf(schemaExtension) != -1)
             key = publicId.substring(publicId.lastIndexOf('/')+1);
         entityValidator.put(key, entityURL);

     * Resolve the requested external entity.
     * @param publicId The public identifier of the entity being referenced
     * @param systemId The system identifier of the entity being referenced
     * @exception SAXException if a parsing exception occurs
    public InputSource resolveEntity(String publicId, String systemId)
        throws SAXException {

        if (publicId != null) {
            this.publicId = publicId;

        // Has this system identifier been registered?
        String entityURL = null;
        if (publicId != null) {
            entityURL = (String) entityValidator.get(publicId);

        // Redirect the schema location to a local destination
        String key = null;
        if (entityURL == null && systemId != null) {
            key = systemId.substring(systemId.lastIndexOf('/')+1);
            entityURL = (String)entityValidator.get(key);

        if (entityURL == null) {
           return (null);

        try {
            return (new InputSource(entityURL));
        } catch (Exception e) {
            throw new SAXException(e);



Other Tomcat examples (source code examples)

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