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Fork of Esoteric Software's Kryo built by Nathan Sweet that replaces Minlog with slf4j as the logging facade. This contains the shaded reflectasm jar to prevent conflicts with other versions of asm.
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/* Copyright (c) 2008, Nathan Sweet
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following
 * conditions are met:
 * 
 * - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided with the distribution.
 * - Neither the name of Esoteric Software nor the names of its contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */

package com.esotericsoftware.kryo.serializers;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

import com.esotericsoftware.kryo.Kryo;
import com.esotericsoftware.kryo.Serializer;
import com.esotericsoftware.kryo.io.Input;
import com.esotericsoftware.kryo.io.Output;

/** Serializes objects that implement the {@link Map} interface.
 * 
 * With the default constructor, a map requires a 1-3 byte header and an extra 4 bytes is written for each key/value pair.
 * @author Nathan Sweet  */
public class MapSerializer extends Serializer {
	private Class keyClass, valueClass;
	private Serializer keySerializer, valueSerializer;
	private boolean keysCanBeNull = true, valuesCanBeNull = true;
	private Class keyGenericType, valueGenericType;

	/** @param keysCanBeNull False if all keys are not null. This saves 1 byte per key if keyClass is set. True if it is not known
	 *           (default). */
	public void setKeysCanBeNull (boolean keysCanBeNull) {
		this.keysCanBeNull = keysCanBeNull;
	}

	/** @param keyClass The concrete class of each key. This saves 1 byte per key. Set to null if the class is not known or varies
	 *           per key (default).
	 * @param keySerializer The serializer to use for each key. */
	public void setKeyClass (Class keyClass, Serializer keySerializer) {
		this.keyClass = keyClass;
		this.keySerializer = keySerializer;
	}

	/** @param valueClass The concrete class of each value. This saves 1 byte per value. Set to null if the class is not known or
	 *           varies per value (default).
	 * @param valueSerializer The serializer to use for each value. */
	public void setValueClass (Class valueClass, Serializer valueSerializer) {
		this.valueClass = valueClass;
		this.valueSerializer = valueSerializer;
	}

	/** @param valuesCanBeNull True if values are not null. This saves 1 byte per value if keyClass is set. False if it is not known
	 *           (default). */
	public void setValuesCanBeNull (boolean valuesCanBeNull) {
		this.valuesCanBeNull = valuesCanBeNull;
	}

	public void setGenerics (Kryo kryo, Class[] generics) {
		keyGenericType = null;
		valueGenericType = null;
		
		if (generics != null && generics.length > 0) {
			if (generics[0] != null && kryo.isFinal(generics[0])) keyGenericType = generics[0];
			if (generics.length > 1 && generics[1] != null && kryo.isFinal(generics[1])) valueGenericType = generics[1];
		}
	}

	public void write (Kryo kryo, Output output, Map map) {
		int length = map.size();
		output.writeInt(length, true);

		Serializer keySerializer = this.keySerializer;
		if (keyGenericType != null) {
			if (keySerializer == null) keySerializer = kryo.getSerializer(keyGenericType);
			keyGenericType = null;
		}
		Serializer valueSerializer = this.valueSerializer;
		if (valueGenericType != null) {
			if (valueSerializer == null) valueSerializer = kryo.getSerializer(valueGenericType);
			valueGenericType = null;
		}

		for (Iterator iter = map.entrySet().iterator(); iter.hasNext();) {
			Entry entry = (Entry)iter.next();
			if (keySerializer != null) {
				if (keysCanBeNull)
					kryo.writeObjectOrNull(output, entry.getKey(), keySerializer);
				else
					kryo.writeObject(output, entry.getKey(), keySerializer);
			} else
				kryo.writeClassAndObject(output, entry.getKey());
			if (valueSerializer != null) {
				if (valuesCanBeNull)
					kryo.writeObjectOrNull(output, entry.getValue(), valueSerializer);
				else
					kryo.writeObject(output, entry.getValue(), valueSerializer);
			} else
				kryo.writeClassAndObject(output, entry.getValue());
		}
	}

	/** Used by {@link #read(Kryo, Input, Class)} to create the new object. This can be overridden to customize object creation, eg
	 * to call a constructor with arguments. The default implementation uses {@link Kryo#newInstance(Class)}. */
	protected Map create (Kryo kryo, Input input, Class type) {
		return kryo.newInstance(type);
	}

	public Map read (Kryo kryo, Input input, Class type) {
		Map map = create(kryo, input, type);
		int length = input.readInt(true);

		Class keyClass = this.keyClass;
		Class valueClass = this.valueClass;

		Serializer keySerializer = this.keySerializer;
		if (keyGenericType != null) {
			keyClass = keyGenericType;
			if (keySerializer == null) keySerializer = kryo.getSerializer(keyClass);
			keyGenericType = null;
		}
		Serializer valueSerializer = this.valueSerializer;
		if (valueGenericType != null) {
			valueClass = valueGenericType;
			if (valueSerializer == null) valueSerializer = kryo.getSerializer(valueClass);
			valueGenericType = null;
		}

		kryo.reference(map);

		for (int i = 0; i < length; i++) {
			Object key;
			if (keySerializer != null) {
				if (keysCanBeNull)
					key = kryo.readObjectOrNull(input, keyClass, keySerializer);
				else
					key = kryo.readObject(input, keyClass, keySerializer);
			} else
				key = kryo.readClassAndObject(input);
			Object value;
			if (valueSerializer != null) {
				if (valuesCanBeNull)
					value = kryo.readObjectOrNull(input, valueClass, valueSerializer);
				else
					value = kryo.readObject(input, valueClass, valueSerializer);
			} else
				value = kryo.readClassAndObject(input);
			map.put(key, value);
		}
		return map;
	}

	protected Map createCopy (Kryo kryo, Map original) {
		return kryo.newInstance(original.getClass());
	}

	public Map copy (Kryo kryo, Map original) {
		Map copy = createCopy(kryo, original);
		for (Iterator iter = original.entrySet().iterator(); iter.hasNext();) {
			Entry entry = (Entry)iter.next();
			copy.put(kryo.copy(entry.getKey()), kryo.copy(entry.getValue()));
		}
		return copy;
	}

	/** 
	 * Used to annotate fields that are maps with specific Kryo serializers for 
	 * their keys or values. 
	 */
	@Retention(RetentionPolicy.RUNTIME)
	@Target(ElementType.FIELD)
	public @interface BindMap {

		/** 
		 * Serializer to be used for keys
		 * 
		 * @return the class used for keys serialization
		 */
		@SuppressWarnings("rawtypes")
		Class keySerializer() default Serializer.class;

		/** 
		 * Serializer to be used for values
		 * 
		 * @return the class used for values serialization 
		 */
		@SuppressWarnings("rawtypes")
		Class valueSerializer() default Serializer.class;

		/** 
		 * Class used for keys
		 * 
		 * @return the class used for keys 
		 */
		Class keyClass() default Object.class;

		/** 
		 * Class used for values
		 * 
		 * @return the class used for values 
		 */
		Class valueClass() default Object.class;

		/** 
		 * Indicates if keys can be null
		 * 
		 * @return true, if keys can be null 
		 */
		boolean keysCanBeNull() default true;

		/** 
		 * Indicates if values can be null
		 * 
		 * @return true, if values can be null 
		 */
		boolean valuesCanBeNull() default true;
	}
}