• SpringBoot整合redis


    SpringBoot操作数据层:spring-data

    Springdataspringboot是齐名的项目!

    说明:在SpringBoot2.x之后,原来使用的jedis被替换为了lettuce

    Jedis:采用的直连,多个线程操作的话,是不安全的,如果想要避免不安全的,使用jedis pool 连接池!更像BIO模式

    Lettuce:采用netty,实例可以在多个线程中进行共享,不存在线程不安全的情况!可以减少线程数据了,更像NIO模式!

     

    先创建一个SpringBoot项目

     

     

     

     

    源码分析:

    public class RedisAutoConfiguration {
        public RedisAutoConfiguration() {
        }

        @Bean
        @ConditionalOnMissingBean(
            name = {"redisTemplate"}
        )
        public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
            RedisTemplate<Object, Object> template = new RedisTemplate();
            template.setConnectionFactory(redisConnectionFactory);
            return template;
        }

        @Bean
        @ConditionalOnMissingBean

    //由于Stringredis中经常使用的类型,所以单独抽出来了一个bean
        public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
            StringRedisTemplate template = new StringRedisTemplate();
            template.setConnectionFactory(redisConnectionFactory);
            return template;
        }
    }

    ConditionalOnMissingBean表是如果你自己再写一个同样的name=’redisTemplate 或者stringRedisTemplate ’,就会使用你的方法而不走源码的方法了,比如:redisTemplate  stringRedisTemplate这两个方法

    连接测试:

    Application.properties文件的配置:
    
    #SpringBoot 所有的配置类,都有一个自动配置类 RedisAutoConfiguration
    #自动配置类都会绑定一个propertiees配置文件 RedisProperties
    spring.redis.host=127.0.0.1
    spring.redis.port=6379
    

      

    package com.zyq;


    import org.junit.jupiter.api.Test;
    import org.springframework.beans.factory.annotation.Autowired;

    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.data.redis.connection.RedisConnection;
    import org.springframework.data.redis.core.RedisTemplate;

    @SpringBootTest
    class Redis02SpringbootApplicationTests {
        @Autowired
       private  RedisTemplate<String,String> redisTemplate;
       @Test
       public void contextLoads() {
    //    redisTemplate  操作不同的数据类型,api和我们的指令是一样的
          //opsForValue 操作字符串 类似String
          //opsForList  操作list 类似list
          //opsForSet 操作set 类似set
          //......
          //除了基本的操作,我们常用的方法都可以直接i通过redisTemplate操作,比如事务,和己本地crud
          //获取redis的连接对象
    //    RedisConnection connection =redisTemplate.getConnectionFactory().getConnection();
    //    connection.flushDb();
    //    connection.flushAll();
          redisTemplate.opsForValue().set("name","yyy");
          System.out.println("==========="+redisTemplate.opsForValue().get("name"));

       }


    }

    运行结果:

    ===========yyy

    如果将上面的代码:

    redisTemplate.opsForValue().set("name","丫丫丫");

    输出结果:

    ===========丫丫丫

    默认使用的是jdk序列化的。

    package com.zyq.pojo;


    import lombok.AllArgsConstructor;
    import lombok.Data;
    import lombok.NoArgsConstructor;
    import org.springframework.stereotype.Component;

    @Component
    @AllArgsConstructor
    @NoArgsConstructor
    @Data
    public class User {
        private String name;
        private int age;
    }

    @Test
    void test1(){
       //真实的开发一般都使用json来传递对象
       User user=new User("丫丫丫",2);
       try {
          //将传入的对象序列化为json字符串
          String value = new ObjectMapper().writeValueAsString(user);
          redisTemplate.opsForValue().set("user",value);
          System.out.println(redisTemplate.opsForValue().get("user"));
       } catch (JsonProcessingException e) {
          e.printStackTrace();
       }

    }

    运行结果:

    {"name":"丫丫丫","age":2}

    如果,我们直接传入对象:

    redisTemplate.opsForValue().set("user",user);

    运行结果:会报一个序列化异常

    我们将要传入的对象序列化

    public class User implements Serializable {
        private String name;
        private int age;
    }

    运行结果;

    User(name=丫丫丫, age=2)

    编写我们自己的redistemplate

    package com.zyq.config;

    import com.fasterxml.jackson.annotation.JsonAutoDetect;
    import com.fasterxml.jackson.annotation.PropertyAccessor;
    import com.fasterxml.jackson.databind.ObjectMapper;
    import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.data.redis.connection.RedisConnectionFactory;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
    import org.springframework.data.redis.serializer.StringRedisSerializer;

    import java.net.UnknownHostException;

    @Configuration
    public class RedisConfig {
        //编写我们的配置类
        @Bean
        @SuppressWarnings("all")
        public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
            RedisTemplate<String, Object> template = new RedisTemplate();
            template.setConnectionFactory(redisConnectionFactory);
            Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
            ObjectMapper objectMapper = new ObjectMapper();
            objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
            objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
            jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
            StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();

            //key采用String的序列化方式
            template.setKeySerializer(stringRedisSerializer);
            //hashkey也采用String的序列化方式
            template.setHashKeySerializer(stringRedisSerializer);
            //value的序列化方式采用jackson
            template.setValueSerializer(jackson2JsonRedisSerializer);
            //hashvalue序列化方式采用jackson
            template.setHashValueSerializer(jackson2JsonRedisSerializer);
            template.afterPropertiesSet();

            return template;
        }

    }

    封装我们经常使用的redisapi

    package com.zyq.util;

    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.stereotype.Component;
    import org.springframework.util.CollectionUtils;

    import java.util.List;
    import java.util.Map;
    import java.util.Set;
    import java.util.concurrent.TimeUnit;

    @Component
    public final class RedisUtil {

        @Autowired
        private RedisTemplate<String, Object> redisTemplate;

        // =============================common============================
        /**
         * 指定缓存失效时间
         * @param key  
         * @param time 时间()
         */
        public boolean expire(String key, long time) {
            try {
                if (time > 0) {
                    redisTemplate.expire(key, time, TimeUnit.SECONDS);
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }

        /**
         * 根据key 获取过期时间
         * @param key 键 不能为null
         * @return 时间() 返回0代表为永久有效
         */
        public long getExpire(String key) {
            return redisTemplate.getExpire(key, TimeUnit.SECONDS);
        }


        /**
         * 判断key是否存在
         * @param key
         * @return true 存在 false不存在
         */
        public boolean hasKey(String key) {
            try {
                return redisTemplate.hasKey(key);
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 删除缓存
         * @param key 可以传一个值 或多个
         */
        @SuppressWarnings("unchecked")
        public void del(String... key) {
            if (key != null && key.length > 0) {
                if (key.length == 1) {
                    redisTemplate.delete(key[0]);
                } else {
                    redisTemplate.delete(CollectionUtils.arrayToList(key));
                }
            }
        }


        // ============================String=============================

        /**
         * 普通缓存获取
         * @param key
         * @return
         */
        public Object get(String key) {
            return key == null ? null : redisTemplate.opsForValue().get(key);
        }

        /**
         * 普通缓存放入
         * @param key   
         * @param value
         * @return true成功 false失败
         */

        public boolean set(String key, Object value) {
            try {
                redisTemplate.opsForValue().set(key, value);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 普通缓存放入并设置时间
         * @param key   
         * @param value
         * @param time  时间() time要大于0 如果time小于等于0 将设置无限期
         * @return true成功 false 失败
         */

        public boolean set(String key, Object value, long time) {
            try {
                if (time > 0) {
                    redisTemplate.opsForValue().set(key, value, time, TimeUnit.SECONDS);
                } else {
                    set(key, value);
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 递增
         * @param key   
         * @param delta 要增加几(大于0)
         */
        public long incr(String key, long delta) {
            if (delta < 0) {
                throw new RuntimeException("递增因子必须大于0");
            }
            return redisTemplate.opsForValue().increment(key, delta);
        }


        /**
         * 递减
         * @param key   
         * @param delta 要减少几(小于0)
         */
        public long decr(String key, long delta) {
            if (delta < 0) {
                throw new RuntimeException("递减因子必须大于0");
            }
            return redisTemplate.opsForValue().increment(key, -delta);
        }


        // ================================Map=================================

        /**
         * HashGet
         * @param key  键 不能为null
         * @param item 项 不能为null
         */
        public Object hget(String key, String item) {
            return redisTemplate.opsForHash().get(key, item);
        }

        /**
         * 获取hashKey对应的所有键值
         * @param key
         * @return 对应的多个键值
         */
        public Map<Object, Object> hmget(String key) {
            return redisTemplate.opsForHash().entries(key);
        }

        /**
         * HashSet
         * @param key
         * @param map 对应多个键值
         */
        public boolean hmset(String key, Map<String, Object> map) {
            try {
                redisTemplate.opsForHash().putAll(key, map);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * HashSet 并设置时间
         * @param key  
         * @param map  对应多个键值
         * @param time 时间()
         * @return true成功 false失败
         */
        public boolean hmset(String key, Map<String, Object> map, long time) {
            try {
                redisTemplate.opsForHash().putAll(key, map);
                if (time > 0) {
                    expire(key, time);
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 向一张hash表中放入数据,如果不存在将创建
         *
         * @param key   
         * @param item  
         * @param value
         * @return true 成功 false失败
         */
        public boolean hset(String key, String item, Object value) {
            try {
                redisTemplate.opsForHash().put(key, item, value);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }

        /**
         * 向一张hash表中放入数据,如果不存在将创建
         *
         * @param key   
         * @param item  
         * @param value
         * @param time  时间() 注意:如果已存在的hash表有时间,这里将会替换原有的时间
         * @return true 成功 false失败
         */
        public boolean hset(String key, String item, Object value, long time) {
            try {
                redisTemplate.opsForHash().put(key, item, value);
                if (time > 0) {
                    expire(key, time);
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 删除hash表中的值
         *
         * @param key  键 不能为null
         * @param item 项 可以使多个 不能为null
         */
        public void hdel(String key, Object... item) {
            redisTemplate.opsForHash().delete(key, item);
        }


        /**
         * 判断hash表中是否有该项的值
         *
         * @param key  键 不能为null
         * @param item 项 不能为null
         * @return true 存在 false不存在
         */
        public boolean hHasKey(String key, String item) {
            return redisTemplate.opsForHash().hasKey(key, item);
        }


        /**
         * hash递增 如果不存在,就会创建一个 并把新增后的值返回
         *
         * @param key  
         * @param item
         * @param by   要增加几(大于0)
         */
        public double hincr(String key, String item, double by) {
            return redisTemplate.opsForHash().increment(key, item, by);
        }


        /**
         * hash递减
         *
         * @param key  
         * @param item
         * @param by   要减少记(小于0)
         */
        public double hdecr(String key, String item, double by) {
            return redisTemplate.opsForHash().increment(key, item, -by);
        }


        // ============================set=============================

        /**
         * 根据key获取Set中的所有值
         * @param key
         */
        public Set<Object> sGet(String key) {
            try {
                return redisTemplate.opsForSet().members(key);
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
        }


        /**
         * 根据value从一个set中查询,是否存在
         *
         * @param key   
         * @param value
         * @return true 存在 false不存在
         */
        public boolean sHasKey(String key, Object value) {
            try {
                return redisTemplate.opsForSet().isMember(key, value);
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 将数据放入set缓存
         *
         * @param key    
         * @param values 值 可以是多个
         * @return 成功个数
         */
        public long sSet(String key, Object... values) {
            try {
                return redisTemplate.opsForSet().add(key, values);
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }
        }


        /**
         * set数据放入缓存
         *
         * @param key    
         * @param time   时间()
         * @param values 值 可以是多个
         * @return 成功个数
         */
        public long sSetAndTime(String key, long time, Object... values) {
            try {
                Long count = redisTemplate.opsForSet().add(key, values);
                if (time > 0)
                    expire(key, time);
                return count;
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }
        }


        /**
         * 获取set缓存的长度
         *
         * @param key
         */
        public long sGetSetSize(String key) {
            try {
                return redisTemplate.opsForSet().size(key);
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }
        }


        /**
         * 移除值为value
         *
         * @param key    
         * @param values 值 可以是多个
         * @return 移除的个数
         */

        public long setRemove(String key, Object... values) {
            try {
                Long count = redisTemplate.opsForSet().remove(key, values);
                return count;
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }
        }

        // ===============================list=================================

        /**
         * 获取list缓存的内容
         *
         * @param key   
         * @param start 开始
         * @param end   结束 0 -1代表所有值
         */
        public List<Object> lGet(String key, long start, long end) {
            try {
                return redisTemplate.opsForList().range(key, start, end);
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
        }


        /**
         * 获取list缓存的长度
         *
         * @param key
         */
        public long lGetListSize(String key) {
            try {
                return redisTemplate.opsForList().size(key);
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }
        }


        /**
         * 通过索引 获取list中的值
         *
         * @param key   
         * @param index 索引 index>=0时, 0 表头,1 第二个元素,依次类推;index<0时,-1,表尾,-2倒数第二个元素,依次类推
         */
        public Object lGetIndex(String key, long index) {
            try {
                return redisTemplate.opsForList().index(key, index);
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
        }


        /**
         * list放入缓存
         *
         * @param key   
         * @param value
         */
        public boolean lSet(String key, Object value) {
            try {
                redisTemplate.opsForList().rightPush(key, value);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * list放入缓存
         * @param key   
         * @param value
         * @param time  时间()
         */
        public boolean lSet(String key, Object value, long time) {
            try {
                redisTemplate.opsForList().rightPush(key, value);
                if (time > 0)
                    expire(key, time);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }

        }


        /**
         * list放入缓存
         *
         * @param key   
         * @param value
         * @return
         */
        public boolean lSet(String key, List<Object> value) {
            try {
                redisTemplate.opsForList().rightPushAll(key, value);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }

        }


        /**
         * list放入缓存
         *
         * @param key   
         * @param value
         * @param time  时间()
         * @return
         */
        public boolean lSet(String key, List<Object> value, long time) {
            try {
                redisTemplate.opsForList().rightPushAll(key, value);
                if (time > 0)
                    expire(key, time);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 根据索引修改list中的某条数据
         *
         * @param key   
         * @param index 索引
         * @param value
         * @return
         */

        public boolean lUpdateIndex(String key, long index, Object value) {
            try {
                redisTemplate.opsForList().set(key, index, value);
                return true;
            } catch (Exception e) {
                e.printStackTrace();
                return false;
            }
        }


        /**
         * 移除N个值为value
         *
         * @param key   
         * @param count 移除多少个
         * @param value
         * @return 移除的个数
         */

        public long lRemove(String key, long count, Object value) {
            try {
                Long remove = redisTemplate.opsForList().remove(key, count, value);
                return remove;
            } catch (Exception e) {
                e.printStackTrace();
                return 0;
            }

        }

    }

    编写测试方法:

    @Test
    void test2(){
       redisUtil.set("name","yyy");
       System.out.println(redisUtil.get("name"));
    }

    运行结果:yyy

    所有的redis操作,其实对于Java开发人员来说,十分的简单,更重要的是要去理解redis的思想和每一种数据结构的用处和作用场景。

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  • 原文地址:https://www.cnblogs.com/dongyaotou/p/13764468.html
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