通过Netty/Socket/C语言三种方式向Redis服务器发送命令

*<number of arguments> CR LF
$<number of bytes of argument 1> CR LF <argument data> CR LF
...
$<number of bytes of argument N> CR LF <argument data> CR LF
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import java.io.IOException;
import java.net.Socket;
public class RedisOfSocket {


    private static final String CRLF = "\r\n";
    public static void main(String[] args) throws IOException {
        String key = "k6";
        String value = "v6";
        sendCmd(key, value);
    }


    private static void sendCmd(String key, String value) throws IOException {


        // 1.建立连接
        Socket client = new Socket("127.0.0.1", 6379);


        // 2.组装命令
        StringBuilder command = new StringBuilder();


        // *<参数个数> CRLF
        String number = "*3" + CRLF;
        command.append(number);


        // $<参数字节数>CRLF<参数>CRLF
        String cmd = "$3" + CRLF + "SET" + CRLF;
        command.append(cmd);


        // $<参数字节数>CRLF<参数>CRLF
        cmd = "$" + key.getBytes().length + CRLF + key + CRLF;
        command.append(cmd);


        // $<参数字节数>CRLF<参数>CRLF
        cmd = "$" + value.getBytes().length + CRLF + value + CRLF;
        command.append(cmd);




        // 3.向服务器发送命令
        client.getOutputStream().write(command.toString().getBytes());






        // 4.接收服务器响应
        byte[] response = new byte[1024];
        int c = client.getInputStream().read(response);
        System.out.println(new String(response, 0, c));
    }
}
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import io.netty.bootstrap.Bootstrap;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
import lombok.extern.slf4j.Slf4j;
import java.net.InetSocketAddress;


@Slf4j
public class RedisOfNetty {


    public static void main(String[] args) {


        Bootstrap bootstrap = new Bootstrap();
        EventLoopGroup group = new NioEventLoopGroup();


        bootstrap.group(group)
                .channel(NioSocketChannel.class)
                .handler(new ChannelInitializer<NioSocketChannel>() {
                    @Override
                    protected void initChannel(NioSocketChannel ch) throws Exception {


                        ChannelPipeline channelPipeline = ch.pipeline();
                        channelPipeline.addLast(new StringEncoder());
                        channelPipeline.addLast(new StringDecoder());
                        // 将自定义的处理器添加到Pipeline里
                        channelPipeline.addLast(new ClientInHandler());


                    }
                });


        bootstrap.connect(new InetSocketAddress("127.0.0.1", 6379));


    }
}
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import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import lombok.extern.slf4j.Slf4j;


//自定义处理器
@Slf4j
public class ClientInHandler extends SimpleChannelInboundHandler<String> {


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


    // 我们的程序连接到Redis服务器之后,会回调这个方法,在这个方法里,向Redis服务器发送SET命令 
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {


        String key = "k9";
        String value = "v9";


        // 2.组装命令
        StringBuilder command = new StringBuilder();


        // *<参数个数> CRLF
        String number = "*3" + CRLF;
        command.append(number);


        // $<参数字节数>CRLF<参数>CRLF
        String cmd = "$3" + CRLF + "SET" + CRLF;
        command.append(cmd);


        // $<参数字节数>CRLF<参数>CRLF
        cmd = "$" + key.getBytes().length + CRLF + key + CRLF;
        command.append(cmd);


        // $<参数字节数>CRLF<参数>CRLF
        cmd = "$" + value.getBytes().length + CRLF + value + CRLF;
        command.append(cmd);




        // 3.向服务器发送命令
        ctx.writeAndFlush(command);




    }




    @Override
    protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {


        System.out.println("接收到服务端的响应: " + msg);


    }
}
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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/un.h>
#include <errno.h>
#include <stddef.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>




int main(int argc, char **argv)
{
    struct sockaddr_in sockaddr;


    int fd = socket(AF_INET, SOCK_STREAM, 0);


    bzero(&sockaddr, sizeof(sockaddr));
    sockaddr.sin_family = AF_INET;
    inet_pton(AF_INET, "127.0.0.1", &sockaddr.sin_addr);
    sockaddr.sin_port=htons(6379);


    // 建立连接
    connect(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr));


    // 发送命令
    write(fd, "*3\r\n", 4);
    write(fd, "$3\r\nSET\r\n", 9);
    write(fd, "$2\r\nk7\r\n", 8);
    write(fd, "$2\r\nv7\r\n", 8);


    // 读取返回值
    char buf[1024];
    memset(buf, '\0', sizeof(buf));
    read(fd, buf, sizeof(buf));
    printf("%s\n", buf);


    close(fd);


    return 0;
}
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