001 /**
002 *
003 * Copyright 2005 The Apache Software Foundation
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.geronimo.kernel.config.xstream;
018
019 import java.io.IOException;
020 import java.io.InputStream;
021 import java.io.InputStreamReader;
022 import java.io.OutputStream;
023 import java.io.Reader;
024 import java.io.PushbackInputStream;
025 import java.io.ObjectStreamConstants;
026 import java.util.Collection;
027
028 import com.thoughtworks.xstream.XStream;
029 import org.apache.geronimo.kernel.config.ConfigurationData;
030 import org.apache.geronimo.kernel.config.ConfigurationMarshaler;
031 import org.apache.geronimo.kernel.config.GBeanState;
032 import org.apache.geronimo.kernel.config.SerializedConfigurationMarshaler;
033
034 /**
035 * @version $Rev: 410741 $ $Date: 2006-05-31 21:35:48 -0700 (Wed, 31 May 2006) $
036 */
037 public class XStreamConfigurationMarshaler implements ConfigurationMarshaler {
038 private static byte[] SERIALIZED_MAGIC = new byte[] {
039 (byte) ((ObjectStreamConstants.STREAM_MAGIC >>> 8) & 0xFF),
040 (byte) ((ObjectStreamConstants.STREAM_MAGIC >>> 0) & 0xFF)
041 };
042
043 public XStreamConfigurationMarshaler() {
044 // create an xstream just to assuer all the required libraries are present
045 XStreamUtil.createXStream();
046 }
047
048 public ConfigurationData readConfigurationData(InputStream in) throws IOException, ClassNotFoundException {
049 PushbackInputStream pushbackInputStream = new PushbackInputStream(in, 2);
050 byte[] streamHeader = new byte[2];
051 if (pushbackInputStream.read(streamHeader) != 2) throw new AssertionError("Cound not read stream header");
052 pushbackInputStream.unread(streamHeader);
053
054 // if this is a serialized config, fallback to the serialization marshaler
055 if (SERIALIZED_MAGIC[0] == streamHeader[0] && SERIALIZED_MAGIC[1] == streamHeader[1]) {
056 return new SerializedConfigurationMarshaler().readConfigurationData(pushbackInputStream);
057 }
058
059 XStream xstream = XStreamUtil.createXStream();
060 Reader reader = new InputStreamReader(pushbackInputStream);
061 ConfigurationData configurationData = (ConfigurationData)xstream.fromXML(reader);
062 return configurationData;
063 }
064
065 public void writeConfigurationData(ConfigurationData configurationData, OutputStream out) throws IOException {
066 XStream xstream = XStreamUtil.createXStream();
067 String xml = xstream.toXML(configurationData);
068
069 out.write(("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
070 "\n" +
071 "<!-- ======================================================== -->\n" +
072 "<!-- Warning - Modification of this file may cause server -->\n" +
073 "<!-- instability. Also, the format of this XML file is -->\n" +
074 "<!-- undocumented and subject to change without notice. -->\n" +
075 "<!-- ======================================================== -->\n" +
076 "\n").getBytes());
077
078 out.write(xml.getBytes());
079 out.flush();
080 }
081
082 public GBeanState newGBeanState(Collection gbeans) {
083 return new XStreamGBeanState(gbeans);
084 }
085 }