package org.jtheque.updates.impl;
import org.jtheque.core.Core;
import org.jtheque.utils.bean.Version;
import org.jtheque.utils.collections.CollectionUtils;
import org.jtheque.utils.io.FileUtils;
import org.jtheque.xml.utils.XML;
import org.jtheque.xml.utils.XMLException;
import org.jtheque.xml.utils.XMLReader;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Node;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.List;
/*
* Copyright JTheque (Baptiste Wicht)
*
* 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.
*/
/**
* A reader for core descriptor.
*
* @author Baptiste Wicht
*/
final class CoreDescriptorReader {
/**
* Utility class, not instantiable.
*/
private CoreDescriptorReader() {
throw new AssertionError();
}
/**
* Read the core descriptor at the specified URL.
*
* @return The core descriptor or null if there were an error during the reading.
*/
static CoreDescriptor readCoreDescriptor() {
try {
return readCoreDescriptor(new URL(Core.DESCRIPTOR_FILE_URL));
} catch (MalformedURLException e) {
return null;
}
}
/**
* Read the core descriptor at the given URL.
*
* @param url The URL to read the core descriptor from.
*
* @return The core descriptor or null if there were a problem reading the file.
*/
private static CoreDescriptor readCoreDescriptor(URL url) {
XMLReader<Node> reader = XML.newJavaFactory().newReader();
try {
reader.openURL(url);
List<CoreVersion> versions = CollectionUtils.newList(5);
for (Object currentNode : reader.getNodes("version", reader.getRootElement())) {
versions.add(readCoreVersion(currentNode, reader));
}
return new CoreDescriptor(versions);
} catch (XMLException e) {
LoggerFactory.getLogger(CoreDescriptorReader.class).error("Unable to read versions file", e);
} finally {
FileUtils.close(reader);
}
return null;
}
/**
* Read the CoreVersion from the given node and using the given reader.
*
* @param currentNode The current node.
* @param reader The reader.
*
* @return The core version.
*
* @throws XMLException If an exception occurs during XML processing.
*/
private static CoreVersion readCoreVersion(Object currentNode, XMLReader<Node> reader) throws XMLException {
List<FileDescriptor> descriptors = CollectionUtils.newList(25);
for (Object libraryNode : reader.getNodes("bundles/bundle", currentNode)) {
descriptors.add(readFileDescriptor(libraryNode, reader));
}
return new CoreVersion(Version.get(reader.readString("@name", currentNode)), descriptors);
}
/**
* Read the file descriptor.
*
* @param currentNode The current node.
* @param reader The XML reader.
*
* @return The FileDescriptor of the current node.
*
* @throws XMLException If an exception occurs during XML parsing.
*/
private static FileDescriptor readFileDescriptor(Object currentNode, XMLReader<Node> reader) throws XMLException {
String name = reader.readString("name", currentNode);
String url = reader.readString("url", currentNode);
String version = reader.readString("version", currentNode);
return new FileDescriptor(name, url, Version.get(version));
}
}