Java tutorial
/* * Copyright (c) 2015 Uber Technologies, Inc. * * 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.uber.tchannel.frames; import com.uber.tchannel.codecs.CodecUtils; import com.uber.tchannel.codecs.MessageCodec; import com.uber.tchannel.codecs.TFrame; import com.uber.tchannel.errors.ErrorType; import com.uber.tchannel.messages.Request; import com.uber.tchannel.tracing.Trace; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufAllocator; import io.netty.channel.ChannelHandlerContext; public final class ErrorFrame extends Frame { private ErrorType errorType; private Trace tracing; private String message; /** * Designated Constructor * * @param id unique of the message * @param errorType the type of error this represents * @param tracing tracing information * @param message human readable string meant for logs */ public ErrorFrame(long id, ErrorType errorType, Trace tracing, String message) { this.id = id; this.errorType = errorType; this.tracing = tracing; this.message = message; } protected ErrorFrame(long id) { this.id = id; } /** * Designated Constructor * * @param id unique of the message * @param errorType the type of error this represents * @param message human readable string meant for logs */ public ErrorFrame(long id, ErrorType errorType, String message) { this.id = id; this.errorType = errorType; this.tracing = new Trace(0, 0, 0, (byte) 0x00); this.message = message; } public FrameType getType() { return FrameType.Error; } public ErrorType getErrorType() { return errorType; } public Trace getTracing() { return tracing; } public String getMessage() { return message; } @Override public String toString() { return String.format("<%s id=%d message=%s>", this.getClass().getSimpleName(), this.getId(), this.message); } @Override public ByteBuf encodeHeader(ByteBufAllocator allocator) { ByteBuf buffer = allocator.buffer(28); // code:1 buffer.writeByte(getErrorType().byteValue()); // tracing:25 CodecUtils.encodeTrace(getTracing(), buffer); // message~2 CodecUtils.encodeString(getMessage(), buffer); return buffer; } @Override public void decode(TFrame tFrame) { // code:1 errorType = ErrorType.fromByte(tFrame.payload.readByte()); // tracing:25 tracing = CodecUtils.decodeTrace(tFrame.payload); // message~2 message = CodecUtils.decodeString(tFrame.payload); } public static ErrorFrame sendError(ErrorType type, String message, Request request, ChannelHandlerContext ctx) { ErrorFrame errorFrame = new ErrorFrame(request.getId(), type, // TODO: get trace from request new Trace(0, 0, 0, (byte) 0x00), message); MessageCodec.write(ctx, errorFrame); request.release(); return errorFrame; } public static ErrorFrame sendError(ErrorType type, String message, long id, ChannelHandlerContext ctx) { ErrorFrame errorFrame = new ErrorFrame(id, type, // TODO: get trace from request new Trace(0, 0, 0, (byte) 0x00), message); MessageCodec.write(ctx, errorFrame); return errorFrame; } }