org.jboss.marshalling.ChainingClassTable Maven / Gradle / Ivy
/*
* JBoss, Home of Professional Open Source
* Copyright 2008, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.marshalling;
import java.util.List;
import java.util.ArrayList;
import java.io.IOException;
import java.io.StreamCorruptedException;
/**
* A class table that multiplexes up to 256 class tables. The protocol works by prepending the custom class table
* with an identifier byte.
*/
public class ChainingClassTable implements ClassTable {
private interface Pair {
X getX();
Y getY();
}
private static Pair pair(final ClassTable classTable, final Writer writer) {
return new Pair() {
public ClassTable getX() {
return classTable;
}
public Writer getY() {
return writer;
}
};
}
private final List> writers;
private final ClassTable[] readers;
/**
* Construct a new instance. The given array may be sparse, but it may not be more than
* 256 elements in length. Class tables are checked in order of increasing array index.
*
* @param classTables the class tables to delegate to
*/
public ChainingClassTable(final ClassTable[] classTables) {
if (classTables == null) {
throw new NullPointerException("classTables is null");
}
readers = classTables.clone();
if (readers.length > 256) {
throw new IllegalArgumentException("Class table array is too long (limit is 256 elements)");
}
writers = new ArrayList>();
for (int i = 0; i < readers.length; i++) {
final ClassTable classTable = readers[i];
if (classTable != null) {
final int idx = i;
writers.add(pair(classTable, new Writer() {
public void writeClass(final Marshaller marshaller, final Class clazz) throws IOException {
marshaller.writeByte(idx);
classTable.getClassWriter(clazz).writeClass(marshaller, clazz);
}
}));
}
}
}
/** {@inheritDoc} */
public Writer getClassWriter(final Class clazz) throws IOException {
for (Pair entry : writers) {
final ClassTable table = entry.getX();
final Writer writer = entry.getY();
if (table.getClassWriter(clazz) != null) {
return writer;
}
}
return null;
}
/** {@inheritDoc} */
public Class readClass(final Unmarshaller unmarshaller) throws IOException, ClassNotFoundException {
final int v = unmarshaller.readByte() & 0xff;
final ClassTable table = readers[v];
if (table == null) {
throw new StreamCorruptedException(String.format("Unknown class table ID %02x encountered", Integer.valueOf(v)));
}
return table.readClass(unmarshaller);
}
}