redis的基本命令,并用netty操作redis(不使用springboot或者spring框架)就单纯的用netty搞。

大家如果对使用netty搞这些http请求什么的感兴趣的,可以参观我自己创建的这个项目。

nanshaws/nettyWeb: 复习一下netty,并打算做一个web项目出来 (github.com)

Redis的基本命令包括:

  1. SET key value:设置指定key的值。

  2. GET key:获取指定key的值。

  3. DEL key:删除指定key。

  4. EXISTS key:检查指定key是否存在。

  5. TTL key:获取指定key的过期时间。

  6. KEYS pattern:查找所有符合指定模式的key。

  7. INCR key:将指定key的值增加1。

  8. DECR key:将指定key的值减少1。

  9. LPUSH key value:将值添加到列表的左侧。

  10. RPUSH key value:将值添加到列表的右侧。

  11. LPOP key:移除并返回列表左侧的值。

  12. RPOP key:移除并返回列表右侧的值。

  13. SADD key member:将成员添加到集合中。

  14. SMEMBERS key:获取集合中的所有成员。

  15. ZADD key score member:将成员添加到有序集合中。

  16. ZRANGE key start stop:按照分数从小到大的顺序获取有序集合中指定范围的成员。

  17. HSET key field value:将哈希表中指定字段的值设置为指定值。

  18. HGET key field:获取哈希表中指定字段的值。

  19. HMGET key field1 [field2]:获取哈希表中指定字段的值列表。

  20. PING:测试Redis服务器是否可用。

用netty操作redis

引入依赖:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.tianfan</groupId>
    <artifactId>nettyTestLearn</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-transport-native-epoll</artifactId>
            <version>4.1.70.Final</version>
        </dependency>

        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
            <version>4.1.86.Final</version>
        </dependency>
        <dependency>
            <groupId>jakarta.activation</groupId>
            <artifactId>jakarta.activation-api</artifactId>
            <version>2.1.2</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.angus</groupId>
            <artifactId>angus-mail</artifactId>
            <version>1.0.0</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.33</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.10</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.30</version>
        </dependency>

<!--        json-->
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.9</version>
        </dependency>


    </dependencies>


</project>

完整代码:

package org.tianfan.example;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.util.concurrent.GenericFutureListener;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class RedisClient {

    String host;    //   目标主机
    int port;       //   目标主机端口

    public RedisClient(String host,int port){
        this.host = host;
        this.port = port;
    }

    public void start() throws Exception{
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            Bootstrap bootstrap = new Bootstrap();
            bootstrap.group(group)
                    .channel(NioSocketChannel.class)
                    .handler(new RedisClientInitializer());

            Channel channel = bootstrap.connect(host, port).sync().channel();
            System.out.println(" connected to host : " + host + ", port : " + port);
            System.out.println(" type redis's command to communicate with redis-server or type 'quit' to shutdown ");
            BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
            ChannelFuture lastWriteFuture = null;
            for (;;) {
                String s = in.readLine();
                if(s.equalsIgnoreCase("quit")) {
                    break;
                }
                System.out.print(">");
                lastWriteFuture = channel.writeAndFlush(s);
                lastWriteFuture.addListener(new GenericFutureListener<ChannelFuture>() {
                    @Override
                    public void operationComplete(ChannelFuture future) throws Exception {
                        if (!future.isSuccess()) {
                            System.err.print("write failed: ");
                            future.cause().printStackTrace(System.err);
                        }
                    }
                });
            }
            if (lastWriteFuture != null) {
                lastWriteFuture.sync();
            }
            System.out.println(" bye ");
        }finally {
            group.shutdownGracefully();
        }
    }

    public static void main(String[] args) throws Exception{
        RedisClient client = new RedisClient("192.168.56.10",6379);
        client.start();
    }

}
package org.tianfan.example;

import io.netty.buffer.ByteBufUtil;
import io.netty.channel.ChannelDuplexHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.handler.codec.CodecException;
import io.netty.handler.codec.redis.*;
import io.netty.util.CharsetUtil;
import io.netty.util.ReferenceCountUtil;

import java.util.ArrayList;
import java.util.List;

public class RedisClientHandler extends ChannelDuplexHandler {


    // 发送 redis 命令
    @Override
    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
        String[] commands = ((String) msg).split("\\s+");
        List<RedisMessage> children = new ArrayList<>(commands.length);
        for (String cmdString : commands) {
            children.add(new FullBulkStringRedisMessage(ByteBufUtil.writeUtf8(ctx.alloc(), cmdString)));
        }
        RedisMessage request = new ArrayRedisMessage(children);
        ctx.write(request, promise);
    }


    // 接收 redis 响应数据
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        RedisMessage redisMessage = (RedisMessage) msg;
        // 打印响应消息
        printAggregatedRedisResponse(redisMessage);
        // 是否资源
        ReferenceCountUtil.release(redisMessage);
    }


    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        System.err.print("exceptionCaught: ");
        cause.printStackTrace(System.err);
        ctx.close();
    }


    private static void printAggregatedRedisResponse(RedisMessage msg) {
        if (msg instanceof SimpleStringRedisMessage) {
            System.out.println(((SimpleStringRedisMessage) msg).content());
        } else if (msg instanceof ErrorRedisMessage) {
            System.out.println(((ErrorRedisMessage) msg).content());
        } else if (msg instanceof IntegerRedisMessage) {
            System.out.println(((IntegerRedisMessage) msg).value());
        } else if (msg instanceof FullBulkStringRedisMessage) {
            System.out.println(getString((FullBulkStringRedisMessage) msg));
        } else if (msg instanceof ArrayRedisMessage) {
            for (RedisMessage child : ((ArrayRedisMessage) msg).children()) {
                printAggregatedRedisResponse(child);
            }
        } else {
            throw new CodecException("unknown message type: " + msg);
        }
    }

    private static String getString(FullBulkStringRedisMessage msg) {
        if (msg.isNull()) {
            return "(null)";
        }
        return msg.content().toString(CharsetUtil.UTF_8);
    }

}
package org.tianfan.example;

import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.handler.codec.redis.RedisArrayAggregator;
import io.netty.handler.codec.redis.RedisBulkStringAggregator;
import io.netty.handler.codec.redis.RedisDecoder;
import io.netty.handler.codec.redis.RedisEncoder;

public class RedisClientInitializer extends ChannelInitializer<Channel> {

    @Override
    protected void initChannel(Channel ch) throws Exception {
        ChannelPipeline pipeline = ch.pipeline();
        pipeline.addLast(new RedisDecoder());
        pipeline.addLast(new RedisBulkStringAggregator());
        pipeline.addLast(new RedisArrayAggregator());
        pipeline.addLast(new RedisEncoder());
        pipeline.addLast(new RedisClientHandler());
    }
}

 结果图:

posted @ 2023-11-12 14:49  过移  阅读(130)  评论(0编辑  收藏  举报  来源