ViaVersion/api/src/main/java/com/viaversion/viaversion/api/type/types/VarIntType.java

91 lines
3.1 KiB
Java

/*
* This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
* Copyright (C) 2016-2023 ViaVersion and contributors
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package com.viaversion.viaversion.api.type.types;
import com.viaversion.viaversion.api.type.Type;
import com.viaversion.viaversion.api.type.TypeConverter;
import io.netty.buffer.ByteBuf;
public class VarIntType extends Type<Integer> implements TypeConverter<Integer> {
private static final int CONTINUE_BIT = 0x80;
private static final int VALUE_BITS = 0x7F;
private static final int MULTI_BYTE_BITS = ~VALUE_BITS;
private static final int MAX_BYTES = 5;
public VarIntType() {
super("VarInt", Integer.class);
}
public int readPrimitive(ByteBuf buffer) {
int value = 0;
int bytes = 0;
byte in;
do {
in = buffer.readByte();
value |= (in & VALUE_BITS) << (bytes++ * 7);
if (bytes > MAX_BYTES) {
throw new RuntimeException("VarInt too big");
}
} while ((in & CONTINUE_BIT) == CONTINUE_BIT);
return value;
}
public void writePrimitive(ByteBuf buffer, int value) {
while ((value & MULTI_BYTE_BITS) != 0) {
buffer.writeByte((value & VALUE_BITS) | CONTINUE_BIT);
value >>>= 7;
}
buffer.writeByte(value);
}
/**
* @deprecated use {@link #readPrimitive(ByteBuf)} for manual reading to avoid wrapping
*/
@Override
@Deprecated
public Integer read(ByteBuf buffer) {
return readPrimitive(buffer);
}
/**
* @deprecated use {@link #writePrimitive(ByteBuf, int)} for manual reading to avoid wrapping
*/
@Override
@Deprecated
public void write(ByteBuf buffer, Integer object) {
writePrimitive(buffer, object);
}
@Override
public Integer from(Object o) {
if (o instanceof Number) {
return ((Number) o).intValue();
} else if (o instanceof Boolean) {
return ((Boolean) o) ? 1 : 0;
}
return (Integer) o;
}
}