tonivade.redis.RedisClient.java Source code

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Here is the source code for tonivade.redis.RedisClient.java

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/*
 * Copyright (c) 2015, Antonio Gabriel Muoz Conejo <antoniogmc at gmail dot com>
 * Distributed under the terms of the MIT License
 */
package tonivade.redis;

import static java.util.Objects.requireNonNull;

import java.util.logging.Logger;

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.PooledByteBufAllocator;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringEncoder;
import io.netty.util.CharsetUtil;
import tonivade.redis.protocol.RedisToken;
import tonivade.redis.protocol.RedisDecoder;
import tonivade.redis.protocol.RedisEncoder;

public class RedisClient implements IRedis {

    private static final Logger LOGGER = Logger.getLogger(RedisClient.class.getName());

    private static final String DELIMITER = "\r\n";

    private static final int BUFFER_SIZE = 1024 * 1024;
    private static final int MAX_FRAME_SIZE = BUFFER_SIZE * 100;

    private final int port;
    private final String host;

    private EventLoopGroup workerGroup;
    private Bootstrap bootstrap;

    private ChannelFuture future;

    private ChannelHandlerContext context;
    private RedisInitializerHandler initHandler;
    private RedisConnectionHandler connectionHandler;

    private final IRedisCallback callback;

    public RedisClient(String host, int port, IRedisCallback callback) {
        this.host = requireNonNull(host);
        this.port = requireRange(port, 1024, 65535);
        this.callback = requireNonNull(callback);
    }

    public void start() {
        workerGroup = new NioEventLoopGroup(Runtime.getRuntime().availableProcessors());
        initHandler = new RedisInitializerHandler(this);
        connectionHandler = new RedisConnectionHandler(this);

        bootstrap = new Bootstrap().group(workerGroup).channel(NioSocketChannel.class)
                .option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
                .option(ChannelOption.SO_RCVBUF, BUFFER_SIZE).option(ChannelOption.SO_SNDBUF, BUFFER_SIZE)
                .option(ChannelOption.SO_KEEPALIVE, true).handler(initHandler);

        try {
            connect();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    public void stop() {
        try {
            if (future != null) {
                future.channel().close();
            }
        } finally {
            workerGroup.shutdownGracefully();
        }
    }

    @Override
    public void channel(SocketChannel channel) {
        LOGGER.info(() -> "connected to server: " + host + ":" + port);

        channel.pipeline().addLast("redisEncoder", new RedisEncoder());
        channel.pipeline().addLast("stringEncoder", new StringEncoder(CharsetUtil.UTF_8));
        channel.pipeline().addLast("linDelimiter", new RedisDecoder(MAX_FRAME_SIZE));
        channel.pipeline().addLast(connectionHandler);
    }

    @Override
    public void connected(ChannelHandlerContext ctx) {
        LOGGER.info(() -> "channel active");

        this.context = ctx;

        callback.onConnect();
    }

    @Override
    public void disconnected(ChannelHandlerContext ctx) {
        LOGGER.info(() -> "client disconected from server: " + host + ":" + port);

        if (this.context != null) {
            callback.onDisconnect();

            this.context = null;
        }
    }

    public void send(String message) {
        writeAndFlush(message + DELIMITER);
    }

    public void send(RedisToken message) {
        writeAndFlush(message);
    }

    @Override
    public void receive(ChannelHandlerContext ctx, RedisToken message) {
        callback.onMessage(message);
    }

    private void connect() {
        LOGGER.info(() -> "trying to connect");

        future = bootstrap.connect(host, port);

        future.syncUninterruptibly();
    }

    private void writeAndFlush(Object message) {
        if (context != null) {
            context.writeAndFlush(message);
        }
    }

    private int requireRange(int value, int min, int max) {
        if (value <= min || value > max) {
            throw new IllegalArgumentException(min + " <= " + value + " < " + max);
        }
        return value;
    }
}