com.helome.messagecenter.master.HttpServerHandler.java Source code

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Here is the source code for com.helome.messagecenter.master.HttpServerHandler.java

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/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package com.helome.messagecenter.master;

import static io.netty.handler.codec.http.HttpHeaders.is100ContinueExpected;
import static io.netty.handler.codec.http.HttpHeaders.isKeepAlive;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_LENGTH;
import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;
import static io.netty.handler.codec.http.HttpResponseStatus.CONTINUE;
import static io.netty.handler.codec.http.HttpResponseStatus.OK;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpObject;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.util.CharsetUtil;

public class HttpServerHandler extends SimpleChannelInboundHandler<Object> {

    private HttpRequest request;
    /** Buffer that stores the response content */
    private final StringBuilder buf = new StringBuilder();

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

    @Override
    protected void messageReceived(ChannelHandlerContext ctx, Object msg) {
        if (msg instanceof HttpRequest) {
            HttpRequest request = this.request = (HttpRequest) msg;

            if (is100ContinueExpected(request)) {
                send100Continue(ctx);
            }
            buf.setLength(0);
            if ("/connection".equals(request.getUri())) {
                buf.append("{\"state\":1,\"connection\":\"192.168.1.13:9000\"}");
            } else {
                buf.append("{\"state\":0}");
            }
            writeResponse(request, ctx);
        }
    }

    private boolean writeResponse(HttpObject currentObj, ChannelHandlerContext ctx) {
        // Decide whether to close the connection or not.
        boolean keepAlive = isKeepAlive(request);
        // Build the response object.
        FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK,
                Unpooled.copiedBuffer(buf.toString(), CharsetUtil.UTF_8));

        response.headers().set(CONTENT_TYPE, "application/json; charset=UTF-8");

        if (keepAlive) {
            // Add 'Content-Length' header only for a keep-alive connection.
            response.headers().set(CONTENT_LENGTH, response.content().readableBytes());
            // Add keep alive header as per:
            // -
            // http://www.w3.org/Protocols/HTTP/1.1/draft-ietf-http-v11-spec-01.html#Connection
            response.headers().set(CONNECTION, HttpHeaders.Values.KEEP_ALIVE);
        }

        // Write the response.
        ctx.write(response);

        return keepAlive;
    }

    private static void send100Continue(ChannelHandlerContext ctx) {
        FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, CONTINUE);
        ctx.write(response);
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }
}