com.twitter.chill.java.ArraysAsListSerializer Maven / Gradle / Ivy
/*
* Copyright 2010 Martin Grotzke
*
* 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.twitter.chill.java;
import com.twitter.chill.IKryoRegistrar;
import com.twitter.chill.SingleRegistrar;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.List;
import java.util.HashMap;
import java.util.Map;
import com.esotericsoftware.kryo.Kryo;
import com.esotericsoftware.kryo.Serializer;
import com.esotericsoftware.kryo.io.Input;
import com.esotericsoftware.kryo.io.Output;
/**
* A kryo {@link Serializer} for lists created via {@link Arrays#asList(Object...)}.
*
* Note: This serializer does not support cyclic references, so if one of the objects
* gets set the list as attribute this might cause an error during deserialization.
*
*
* @author Martin Grotzke
*/
public class ArraysAsListSerializer extends Serializer> {
private static final Map, Class> primitives = new HashMap, Class>(8, 1.0F);
static {
primitives.put(byte.class, Byte.class);
primitives.put(short.class, Short.class);
primitives.put(int.class, Integer.class);
primitives.put(long.class, Long.class);
primitives.put(char.class, Character.class);
primitives.put(float.class, Float.class);
primitives.put(double.class, Double.class);
primitives.put(boolean.class, Boolean.class);
}
static public IKryoRegistrar registrar() {
return new SingleRegistrar(Arrays.asList("").getClass(), new ArraysAsListSerializer());
}
private Field _arrayField;
public ArraysAsListSerializer() {
try {
_arrayField = Class.forName( "java.util.Arrays$ArrayList" ).getDeclaredField( "a" );
_arrayField.setAccessible( true );
} catch ( final Exception e ) {
throw new RuntimeException( e );
}
}
@Override
public List read(final Kryo kryo, final Input input, final Class> type) {
final int length = input.readInt(true);
Class componentType = kryo.readClass(input).getType();
try {
final Object items = Array.newInstance(getBoxedClass(componentType), length);
for (int i = 0; i < length; i++) {
Array.set(items, i, kryo.readClassAndObject(input));
}
return Arrays.asList((Object[]) items);
} catch (final Exception e) {
throw new RuntimeException(e);
}
}
@Override
public void write(final Kryo kryo, final Output output, final List obj) {
try {
final Object[] array = (Object[]) _arrayField.get(obj);
output.writeInt(array.length, true);
final Class componentType = array.getClass().getComponentType();
kryo.writeClass(output, componentType);
for (final Object item : array) {
kryo.writeClassAndObject(output, item);
}
} catch (final RuntimeException e) {
// Don't eat and wrap RuntimeExceptions because the ObjectBuffer.write...
// handles SerializationException specifically (resizing the buffer)...
throw e;
} catch (final Exception e) {
throw new RuntimeException(e);
}
}
private static Class getBoxedClass(final Class c) {
if (c.isPrimitive()) {
Class x;
return (x = primitives.get(c)) != null ? x : c;
}
return c;
}
}