| /* |
| * Copyright 2009 Google Inc. |
| * |
| * 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 com.google.gwt.uibinder.rebind; |
| |
| import com.google.gwt.dev.util.collect.Sets; |
| |
| import org.xml.sax.EntityResolver; |
| import org.xml.sax.InputSource; |
| import org.xml.sax.SAXException; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.Collections; |
| import java.util.Set; |
| |
| /** |
| * Does special handling of external entities encountered by sax xml parser, |
| * e.g. the uri in |
| * |
| * <pre> |
| * <!DOCTYPE gwt:UiBinder |
| SYSTEM "http://google-web-toolkit.googlecode.com/files/xhtml.ent"></pre> |
| * <p> |
| * Specifically, if the requested uri starts with |
| * <code>http://google-web-toolkit.googlecode.com/files</code>, provide the |
| * contents from a built in resource rather than allowing sax to make a network |
| * request. |
| */ |
| class GwtResourceEntityResolver implements EntityResolver { |
| interface ResourceLoader { |
| InputStream fetch(String name); |
| } |
| |
| private static final Set<String> EXTERNAL_PREFIXES = Collections.unmodifiableSet(Sets.create(new String[] { |
| "http://google-web-toolkit.googlecode.com/files/", |
| "http://dl.google.com/gwt/DTD/", |
| "https://dl-ssl.google.com/gwt/DTD/" |
| })); |
| |
| private static final String RESOURCES = "com/google/gwt/uibinder/resources/"; |
| |
| private final ResourceLoader resourceLoader; |
| |
| public GwtResourceEntityResolver() { |
| this(new ResourceLoader() { |
| public InputStream fetch(String name) { |
| return UiBinderGenerator.class.getClassLoader().getResourceAsStream( |
| name); |
| } |
| }); |
| } |
| |
| /** |
| * For testing. |
| */ |
| GwtResourceEntityResolver(ResourceLoader resourceLoader) { |
| this.resourceLoader = resourceLoader; |
| } |
| |
| public InputSource resolveEntity(String publicId, String systemId) |
| throws SAXException, IOException { |
| String matchingPrefix = findMatchingPrefix(systemId); |
| if (matchingPrefix == null) { |
| // Not our problem, return null and sax will find it |
| return null; |
| } |
| |
| String name = RESOURCES |
| + systemId.substring(matchingPrefix.length()); |
| InputStream resourceStream = resourceLoader.fetch(name); |
| |
| if (resourceStream == null) { |
| /* |
| * They're asking for another DTD resource that we don't short circuit, |
| * Return null and let Sax find it on the interweb. |
| */ |
| return null; |
| } |
| |
| InputSource inputSource = new InputSource(resourceStream); |
| inputSource.setPublicId(publicId); |
| inputSource.setSystemId(systemId); |
| return inputSource; |
| } |
| |
| private String findMatchingPrefix(String systemId) { |
| for (String prefix : EXTERNAL_PREFIXES) { |
| if (systemId.startsWith(prefix)) { |
| return prefix; |
| } |
| } |
| return null; |
| } |
| } |