minecraft-src/net/minecraft/network/Varint21LengthFieldPrepender.java
2025-07-04 01:41:11 +03:00

29 lines
960 B
Java

package net.minecraft.network;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.handler.codec.EncoderException;
import io.netty.handler.codec.MessageToByteEncoder;
/**
* Prepends each frame ("packet") with its length encoded as a VarInt. Every frame's length must fit within a 3-byte VarInt.
*
* @see Varint21FrameDecoder
*/
@Sharable
public class Varint21LengthFieldPrepender extends MessageToByteEncoder<ByteBuf> {
public static final int MAX_VARINT21_BYTES = 3;
protected void encode(ChannelHandlerContext context, ByteBuf encoder, ByteBuf decoder) {
int i = encoder.readableBytes();
int j = VarInt.getByteSize(i);
if (j > 3) {
throw new EncoderException("Packet too large: size " + i + " is over 8");
} else {
decoder.ensureWritable(j + i);
VarInt.write(decoder, i);
decoder.writeBytes(encoder, encoder.readerIndex(), i);
}
}
}