SpringBoot整合redis+lettuce的方法详解

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.1.0</version>
    </parent>
    <groupId>com.example</groupId>
    <artifactId>RedisLettuceDemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>RedisLettuceDemo</name>
    <description>RedisLettuceDemo</description>
    <properties>
        <java.version>17</java.version>
        <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>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>2.0.32</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
        </dependency>
    </dependencies>

server:
  port: 8080  # 设置访问端口
spring:
  redis:
    host: localhost
    port: 6379
    password: 123456
    database: 0
    ssl: false
    pool:
      maxIdle: 100
      minIdle: 0
      maxTotal: 100
      maxWaitMillis: 500
      testOnBorrow: false
      testOnReturn: true
      testWhileIdle: true

//Redis服务器地址
    @Value("${spring.redis.host}")
    private String host;
    //Redis服务端口
    @Value("${spring.redis.port}")
    private Integer port;
    //Redis密码
    @Value("${spring.redis.password}")
    private String password;
    //是否需要SSL
    @Value("${spring.redis.ssl}")
    private Boolean ssl;
    //Redis默认库，一共0～15
    @Value("${spring.redis.database}")
    private Integer database;
    //Lettuce连接配置（Redis单机版实例）
    @Bean(name = "redisClient")
    public RedisClient redisClient() {
        RedisURI uri = RedisURI.Builder.redis(this.host, this.port)
                .withDatabase(this.database)
                .build();
        return RedisClient.create(uri);
    }

@Resource
    RedisClient redisClient;
    //设置可分配的最大Redis实例数量
    @Value("${spring.redis.pool.maxTotal}")
    private Integer maxTotal;
    //设置最多空闲的Redis实例数量
    @Value("${spring.redis.pool.maxIdle}")
    private Integer maxIdle;
    //归还Redis实例时，检查有消息，如果失败，则销毁实例
    @Value("${spring.redis.pool.testOnReturn}")
    private Boolean testOnReturn;
    //当Redis实例处于空闲壮体啊时检查有效性，默认flase
    @Value("${spring.redis.pool.testWhileIdle}")
    private Boolean testWhileIdle;
    //Apache-Common-Pool是一个对象池，用于缓存Redis连接，
    //因为Letture本身基于Netty的异步驱动，但基于Servlet模型的同步访问时，连接池是必要的
    //连接池可以很好的复用连接，减少重复的IO消耗与RedisURI创建实例的性能消耗
    @Getter
    GenericObjectPool<StatefulRedisConnection<String, String>> redisConnectionPool;
    //Servlet初始化时先初始化Lettuce连接池
    @PostConstruct
    private void init() {
        GenericObjectPoolConfig<StatefulRedisConnection<String, String>> redisPoolConfig
                = new GenericObjectPoolConfig<>();
        redisPoolConfig.setMaxIdle(this.maxIdle);
        redisPoolConfig.setMinIdle(0);
        redisPoolConfig.setMaxTotal(this.maxTotal);
        redisPoolConfig.setTestOnReturn(this.testOnReturn);
        redisPoolConfig.setTestWhileIdle(this.testWhileIdle);
        redisPoolConfig.setMaxWaitMillis(1000);
        this.redisConnectionPool =
                ConnectionPoolSupport.createGenericObjectPool(() -> redisClient.connect(), redisPoolConfig);
    }
    //Servlet销毁时先销毁Lettuce连接池
    @PreDestroy
    private void destroy() {
        redisConnectionPool.close();
        redisClient.shutdown();
    }

@Autowired
    LettucePoolConfig lettucePoolConfig;
    //编写executeSync方法，在方法中，获取Redis连接，利用Callback操作Redis，最后释放连接，并返回结果
    //这里使用的同步的方式执行cmd指令
    public <T> T executeSync(SyncCommandCallback<T> callback) {
        //这里利用try的语法糖，执行完，自动给释放连接
        try (StatefulRedisConnection<String, String> connection = lettucePoolConfig.getRedisConnectionPool().borrowObject()) {
            //开启自动提交，如果false，命令会被缓冲，调用flushCommand()方法发出
            connection.setAutoFlushCommands(true);
            //设置为同步模式
            RedisCommands<String, String> commands = connection.sync();
            //执行传入的实现类
            return callback.doInConnection(commands);
        } catch (Exception e) {
            log.error(e.getMessage());
            throw new RuntimeException(e);
        }
    }
    //分装一个set方法
    public String set(final String key, final String val) {
        return executeSync(commands -> commands.set(key, val));
    }
    //分装一个get方法
    public String get(final String key) {
        return executeSync(commands -> commands.get(key));
    }

    //抽象方法，为了简化代码，便于传入回调函数
    T doInConnection(RedisCommands<String, String> commands);

@Autowired
    LettuceUtil lettuceUtil;
    /**
     * 使用Lettuce工具类，调用Redis的Set指令
     * http://127.0.0.1:8080/lettuce/set?key=name&val=ipipman
     *
     * @param key
     * @param val
     * @return
     */
    @GetMapping("/set")
    public Object setItem(@RequestParam(name = "key", required = true) String key,
                          @RequestParam(name = "val", required = true) String val) {
        return lettuceUtil.set(key, val);
    }
    /**
     * 使用Lettuce工具类，调用Redis的Get指令
     * http://127.0.0.1:8080/lettuce/get?key=name
     *
     * @param key
     * @return
     */
    @GetMapping("/get")
    public Object getItem(@RequestParam(name = "key", required = true) String key) {
        return lettuceUtil.get(key);
    }