DefaultArraySerializers.java

/* Copyright (c) 2008-2022, 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 static com.esotericsoftware.kryo.Kryo.*;

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

import java.lang.reflect.Array;
import java.lang.reflect.Modifier;

/** Contains many serializer classes for specific array types that are provided by {@link Kryo#addDefaultSerializer(Class, Class)
 * default}.
 * @author Nathan Sweet */
public class DefaultArraySerializers {
	public static class ByteArraySerializer extends Serializer<byte[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, byte[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeBytes(object);
		}

		public byte[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readBytes(length - 1);
		}

		public byte[] copy (Kryo kryo, byte[] original) {
			byte[] copy = new byte[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class IntArraySerializer extends Serializer<int[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, int[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeInts(object, 0, object.length, false);
		}

		public int[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readInts(length - 1, false);
		}

		public int[] copy (Kryo kryo, int[] original) {
			int[] copy = new int[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class FloatArraySerializer extends Serializer<float[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, float[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeFloats(object, 0, object.length);
		}

		public float[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readFloats(length - 1);
		}

		public float[] copy (Kryo kryo, float[] original) {
			float[] copy = new float[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class LongArraySerializer extends Serializer<long[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, long[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeLongs(object, 0, object.length, false);
		}

		public long[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readLongs(length - 1, false);
		}

		public long[] copy (Kryo kryo, long[] original) {
			long[] copy = new long[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class ShortArraySerializer extends Serializer<short[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, short[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeShorts(object, 0, object.length);
		}

		public short[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readShorts(length - 1);
		}

		public short[] copy (Kryo kryo, short[] original) {
			short[] copy = new short[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class CharArraySerializer extends Serializer<char[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, char[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeChars(object, 0, object.length);
		}

		public char[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readChars(length - 1);
		}

		public char[] copy (Kryo kryo, char[] original) {
			char[] copy = new char[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class DoubleArraySerializer extends Serializer<double[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, double[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			output.writeDoubles(object, 0, object.length);
		}

		public double[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			return input.readDoubles(length - 1);
		}

		public double[] copy (Kryo kryo, double[] original) {
			double[] copy = new double[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class BooleanArraySerializer extends Serializer<boolean[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, boolean[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			for (int i = 0, n = object.length; i < n; i++)
				output.writeBoolean(object[i]);
		}

		public boolean[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			boolean[] array = new boolean[--length];
			for (int i = 0; i < length; i++)
				array[i] = input.readBoolean();
			return array;
		}

		public boolean[] copy (Kryo kryo, boolean[] original) {
			boolean[] copy = new boolean[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class StringArraySerializer extends Serializer<String[]> {
		{
			setAcceptsNull(true);
		}

		public void write (Kryo kryo, Output output, String[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			output.writeVarInt(object.length + 1, true);
			if (kryo.getReferences() && kryo.getReferenceResolver().useReferences(String.class)) {
				Serializer serializer = kryo.getSerializer(String.class);
				for (int i = 0, n = object.length; i < n; i++)
					kryo.writeObjectOrNull(output, object[i], serializer);
			} else {
				for (int i = 0, n = object.length; i < n; i++)
					output.writeString(object[i]);
			}
		}

		public String[] read (Kryo kryo, Input input, Class type) {
			int length = input.readVarInt(true);
			if (length == NULL) return null;
			String[] array = new String[--length];
			if (kryo.getReferences() && kryo.getReferenceResolver().useReferences(String.class)) {
				Serializer serializer = kryo.getSerializer(String.class);
				for (int i = 0; i < length; i++)
					array[i] = kryo.readObjectOrNull(input, String.class, serializer);
			} else {
				for (int i = 0; i < length; i++)
					array[i] = input.readString();
			}
			return array;
		}

		public String[] copy (Kryo kryo, String[] original) {
			String[] copy = new String[original.length];
			System.arraycopy(original, 0, copy, 0, copy.length);
			return copy;
		}
	}

	public static class ObjectArraySerializer extends Serializer<Object[]> {
		private boolean elementsAreSameType;
		private boolean elementsCanBeNull = true;
		private final Class type;

		{
			setAcceptsNull(true);
		}

		public ObjectArraySerializer (Kryo kryo, Class type) {
			this.type = type;
			Class componentType = type.getComponentType();
			boolean isFinal = 0 != (componentType.getModifiers() & Modifier.FINAL);
			if (isFinal) setElementsAreSameType(true);
		}

		public void write (Kryo kryo, Output output, Object[] object) {
			if (object == null) {
				output.writeByte(NULL);
				return;
			}
			int n = object.length;
			output.writeVarInt(n + 1, true);
			Class elementClass = object.getClass().getComponentType();
			if (elementsAreSameType || kryo.isFinal(elementClass)) {
				Serializer elementSerializer = kryo.getSerializer(elementClass);
				if (elementsCanBeNull) {
					for (int i = 0; i < n; i++)
						kryo.writeObjectOrNull(output, object[i], elementSerializer);
				} else {
					for (int i = 0; i < n; i++)
						kryo.writeObject(output, object[i], elementSerializer);
				}
			} else {
				for (int i = 0; i < n; i++)
					kryo.writeClassAndObject(output, object[i]);
			}
		}

		public Object[] read (Kryo kryo, Input input, Class type) {
			int n = input.readVarInt(true);
			if (n == NULL) return null;
			n--;
			Object[] object = (Object[])Array.newInstance(type.getComponentType(), n);
			kryo.reference(object);
			Class elementClass = type.getComponentType();
			if (elementsAreSameType || kryo.isFinal(elementClass)) {
				Serializer elementSerializer = kryo.getSerializer(elementClass);
				if (elementsCanBeNull) {
					for (int i = 0; i < n; i++)
						object[i] = kryo.readObjectOrNull(input, elementClass, elementSerializer);
				} else {
					for (int i = 0; i < n; i++)
						object[i] = kryo.readObject(input, elementClass, elementSerializer);
				}
			} else {
				for (int i = 0; i < n; i++)
					object[i] = kryo.readClassAndObject(input);
			}
			return object;
		}

		public Object[] copy (Kryo kryo, Object[] original) {
			int n = original.length;
			Object[] copy = (Object[])Array.newInstance(original.getClass().getComponentType(), n);
			kryo.reference(copy);
			for (int i = 0; i < n; i++)
				copy[i] = kryo.copy(original[i]);
			return copy;
		}

		/** @param elementsCanBeNull False if all elements are not null. This saves 1 byte per element if the array type is final or
		 *           elementsAreSameClassAsType is true. True if it is not known (default). */
		public void setElementsCanBeNull (boolean elementsCanBeNull) {
			this.elementsCanBeNull = elementsCanBeNull;
		}

		/** @param elementsAreSameType True if all elements are the same type as the array (ie they don't extend the array type).
		 *           This saves 1 byte per element. If the element type is final this saves 0 bytes per element. Set to false if the
		 *           elements may extend the array type (default). */
		public void setElementsAreSameType (boolean elementsAreSameType) {
			this.elementsAreSameType = elementsAreSameType;
		}
	}
}