src/main/java/us/myles/ViaVersion/util/PipelineUtil.java

package us.myles.ViaVersion.util;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.MessageToByteEncoder;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

public class PipelineUtil {
    private static Method DECODE_METHOD;
    private static Method ENCODE_METHOD;

    static {
        try {
            DECODE_METHOD = ByteToMessageDecoder.class.getDeclaredMethod("decode", ChannelHandlerContext.class, ByteBuf.class, List.class);
            DECODE_METHOD.setAccessible(true);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
            System.out.println("Netty issue?");
        }
        try {
            ENCODE_METHOD = MessageToByteEncoder.class.getDeclaredMethod("encode", ChannelHandlerContext.class, Object.class, ByteBuf.class);
            ENCODE_METHOD.setAccessible(true);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
            System.out.println("Netty issue?");
        }
    }

    public static List<Object> callDecode(ByteToMessageDecoder decoder, ChannelHandlerContext ctx, Object input) throws InvocationTargetException {
        List<Object> output = new ArrayList<>();
        try {
            PipelineUtil.DECODE_METHOD.invoke(decoder, ctx, input, output);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
        return output;
    }

    public static void callEncode(MessageToByteEncoder encoder, ChannelHandlerContext ctx, Object msg, ByteBuf output) throws InvocationTargetException {
        try {
            PipelineUtil.ENCODE_METHOD.invoke(encoder, ctx, msg, output);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }

    public static boolean containsCause(Throwable t, Class<? extends Throwable> c) {
        while (t != null) {
            t = t.getCause();
            if (t != null)
                if (c.isAssignableFrom(t.getClass())) return true;
        }
        return false;
    }
}