28. SpringBoot 集成Redis

1.引入依賴：

<dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

 

2.配置redis

spring.redis.host=127.0.0.1

 

 

3.Springboot 配置類

package org.springframework.boot.autoconfigure.data.redis;

import java.net.UnknownHostException;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;

@Configuration
@ConditionalOnClass({RedisOperations.class})
@EnableConfigurationProperties({RedisProperties.class})
@Import({LettuceConnectionConfiguration.class, JedisConnectionConfiguration.class})
public class RedisAutoConfiguration {
    public RedisAutoConfiguration() {
    }

    @Bean
    @ConditionalOnMissingBean(
        name = {"redisTemplate"}　　　　//當Spring容器中沒有名稱為redisTemplate的容器時，才初始化此Bean
    )
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, Object> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }

    @Bean
    @ConditionalOnMissingBean　　　　　　//當Spring容器中沒有下面定義的類型的Bean的時候，才加載下面的Bean public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        StringRedisTemplate template = new StringRedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }
}

 看到這個@ConditionalOnMissingBean注解后，就知道如果Spring容器中自有了 RedisTemplate對象了，這個框架自帶的自動配置的RedisTemplate不會實例化。因此我們可以直接自己寫個配置類，配置 RedisTemplate。

這個 RedisTemplate的泛型是<Object,Object>，寫代碼不方便，需要寫好多類型轉換的代碼；

StringRedisTemplate的泛型是<String,String> 可以將JavaBean通過fastJson搞成String 傳到Redis中保存，再從Redis中獲取到字符串后再通過FastJson轉化成Java。

 

package org.springframework.data.redis.core;

import org.springframework.data.redis.*;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.StringRedisConnection;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

public class StringRedisTemplate extends RedisTemplate<String, String> {

    /**
     * Constructs a new <code>StringRedisTemplate</code> instance. {@link #setConnectionFactory(RedisConnectionFactory)}
     * and {@link #afterPropertiesSet()} still need to be called.
     */
    public StringRedisTemplate() {
        setKeySerializer(RedisSerializer.string());
        setValueSerializer(RedisSerializer.string());
        setHashKeySerializer(RedisSerializer.string());
        setHashValueSerializer(RedisSerializer.string());
    }

    /**
     * Constructs a new <code>StringRedisTemplate</code> instance ready to be used.
     *
     * @param connectionFactory connection factory for creating new connections
     */
    public StringRedisTemplate(RedisConnectionFactory connectionFactory) {
        this();
        setConnectionFactory(connectionFactory);
        afterPropertiesSet();
    }

    protected RedisConnection preProcessConnection(RedisConnection connection, boolean existingConnection) {
        return new DefaultStringRedisConnection(connection);
    }
}

 

4.測試類

@RunWith(SpringRunner.class)
@SpringBootTest
public class Springboot01CacheApplicationTests {
    @Autowired
    EmployeeMapper employeeMapper;

    @Autowired
    StringRedisTemplate stringRedisTemplate;  //操作k-v都是字符串的

    @Autowired
    RedisTemplate redisTemplate;  //k-v都是對象的

    @Autowired
    RedisTemplate<Object, User> userRedisTemplate;


    /**
     * Redis常見的五大數據類型
     *  String（字符串）、List（列表）、Set（集合）、Hash（散列）、ZSet（有序集合）
     *  stringRedisTemplate.opsForValue()[String（字符串）]
     *  stringRedisTemplate.opsForList()[List（列表）]
     *  stringRedisTemplate.opsForSet()[Set（集合）]
     *  stringRedisTemplate.opsForHash()[Hash（散列）]
     *  stringRedisTemplate.opsForZSet()[ZSet（有序集合）]
     */
    @Test
    public void test01(){
        //給redis中保存數據
        //stringRedisTemplate.opsForValue().append("msg","hello");
//        String msg = stringRedisTemplate.opsForValue().get("msg");
//        System.out.println(msg);

//        stringRedisTemplate.opsForList().leftPush("mylist","1");   這個會產生bug,需要將redis.conf配置文件中的stop-writes-on-bgsave-error 的值改為no //        stringRedisTemplate.opsForList().leftPush("mylist","2");
    }

    //測試保存對象
    @Test
    public void test02(){
        User user01 = employeeMapper.getEmpById(1);
        //默認如果保存對象，使用jdk序列化機制，序列化后的數據保存到redis中
        //redisTemplate.opsForValue().set("emp-01",user01);
        //1、將數據以json的方式保存
         //(1)自己將對象轉為json
         //(2)redisTemplate默認的序列化規則；改變默認的序列化規則；
        userRedisTemplate.opsForValue().set("emp-01",user01);
    }

    @Test
    public void contextLoads() {

        Employee empById = employeeMapper.getEmpById(1);
        System.out.println(empById);

    }

}

 

5.序列化解決亂碼問題

　　但是springboot 用redids保存對象時，需要對象實現序列化。而SpringBoot為Redis實現的默認序列化機制是Java的序列化。這樣存到Redis中的數據沒有辦法給人讀懂，是一堆亂碼。這就需要我們重新設置序列化

　　5.1.0）默認的序列化類

public class RedisTemplate<K, V> extends RedisAccessor implements RedisOperations<K, V>, BeanClassLoaderAware {

    private boolean enableDefaultSerializer = true;
    @Nullable
    private RedisSerializer<?> defaultSerializer;

    public void afterPropertiesSet() {
           super.afterPropertiesSet();
            boolean defaultUsed = false;
            if (this.defaultSerializer == null) {
                    this.defaultSerializer = new JdkSerializationRedisSerializer(this.classLoader != null ? this.classLoader : this.getClass().getClassLoader());
            }
        ……..
    }
}

 

　　5.1.1）默認序列化機制保存的效果：userRedisTemplate.opsForValue().set("emp-01",user01);

 

5.2.0）自定義序列化機制類

@Configuration
public class RedisConfig {

    @Bean
    public RedisTemplate<Object, User> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, User> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        Jackson2JsonRedisSerializer jse = new Jackson2JsonRedisSerializer(User.class);
        template.setDefaultSerializer(jse); return template;
    }
}

 

5.2.1）按JavaBean自定義序列化后的保存效果：（局限性太大，不推薦使用）

 

5.2.2） 自定義泛型為<String,Object>的RedisTemplate

package com.everjiankang.demo.redis;
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 com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;

@Configuration
public class RedisConfig {
    @Bean
    @SuppressWarnings("all")
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, Object> template = new RedisTemplate<String, Object>();
        template.setConnectionFactory(factory);
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
        // key采用String的序列化方式
        template.setKeySerializer(stringRedisSerializer);
        // hash的key也采用String的序列化方式
        template.setHashKeySerializer(stringRedisSerializer);
        // value序列化方式采用jackson
        template.setValueSerializer(jackson2JsonRedisSerializer);
        // hash的value序列化方式采用jackson
        template.setHashValueSerializer(jackson2JsonRedisSerializer);
        template.afterPropertiesSet();
        return template;
    }
}

 

package com.everjiankang.miaosha.redis;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

@Component
public final class RedisUtil {
    @Autowired
    private RedisTemplate<String, Object> redisTemplate;
    // =============================common============================
    /**
     * 指定緩存失效時間
     * @param key 鍵
     * @param time 時間(秒)
     * @return
     */
    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;
        }
    }
    /**
     * 根據key 獲取過期時間
     * @param key 鍵 不能為null
     * @return 時間(秒) 返回0代表為永久有效
     */
    public long getExpire(String key) {
        return redisTemplate.getExpire(key, TimeUnit.SECONDS);
    }
    /**
     * 判斷key是否存在
     * @param key 鍵
     * @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;
        }
    }
    /**
     * 刪除緩存
     * @param key 可以傳一個值 或多個
     */
    @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=============================
    /**
     * 普通緩存獲取
     * @param key 鍵
     * @return 值
     */
    public Object get(String key) {
        return key == null ? null : redisTemplate.opsForValue().get(key);
    }
    /**
     * 普通緩存放入
     * @param key 鍵
     * @param value 值
     * @return true成功 false失敗
     */
    public boolean set(String key, Object value) {
        try {
            redisTemplate.opsForValue().set(key, value);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
    /**
     * 普通緩存放入並設置時間
     * @param key 鍵
     * @param value 值
     * @param time 時間(秒) time要大於0 如果time小於等於0 將設置無限期
     * @return true成功 false 失敗
     */
    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;
        }
    }
    /**
     * 遞增
     * @param key 鍵
     * @param delta 要增加幾(大於0)
     * @return
     */
    public long incr(String key, long delta) {
        if (delta < 0) {
            throw new RuntimeException("遞增因子必須大於0");
        }
        return redisTemplate.opsForValue().increment(key, delta);
    }
    /**
     * 遞減
     * @param key 鍵
     * @param delta 要減少幾(小於0)
     * @return
     */
    public long decr(String key, long delta) {
        if (delta < 0) {
            throw new RuntimeException("遞減因子必須大於0");
        }
        return redisTemplate.opsForValue().increment(key, -delta);
    }
    // ================================Map=================================
    /**
     * HashGet
     * @param key 鍵 不能為null
     * @param item 項 不能為null
     * @return 值
     */
    public Object hget(String key, String item) {
        return redisTemplate.opsForHash().get(key, item);
    }
    /**
     * 獲取hashKey對應的所有鍵值
     * @param key 鍵
     * @return 對應的多個鍵值
     */
    public Map<Object, Object> hmget(String key) {
        return redisTemplate.opsForHash().entries(key);
    }
    /**
     * HashSet
     * @param key 鍵
     * @param map 對應多個鍵值
     * @return true 成功 false 失敗
     */
    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 並設置時間
     * @param key 鍵
     * @param map 對應多個鍵值
     * @param time 時間(秒)
     * @return true成功 false失敗
     */
    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;
        }
    }
    /**
     * 向一張hash表中放入數據,如果不存在將創建
     * @param key 鍵
     * @param item 項
     * @param value 值
     * @return true 成功 false失敗
     */
    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;
        }
    }
    /**
     * 向一張hash表中放入數據,如果不存在將創建
     * @param key 鍵
     * @param item 項
     * @param value 值
     * @param time 時間(秒) 注意:如果已存在的hash表有時間,這里將會替換原有的時間
     * @return true 成功 false失敗
     */
    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;
        }
    }
    /**
     * 刪除hash表中的值
     * @param key 鍵 不能為null
     * @param item 項 可以使多個 不能為null
     */
    public void hdel(String key, Object... item) {
        redisTemplate.opsForHash().delete(key, item);
    }
    /**
     * 判斷hash表中是否有該項的值
     * @param key 鍵 不能為null
     * @param item 項 不能為null
     * @return true 存在 false不存在
     */
    public boolean hHasKey(String key, String item) {
        return redisTemplate.opsForHash().hasKey(key, item);
    }
    /**
     * hash遞增 如果不存在,就會創建一個 並把新增后的值返回
     * @param key 鍵
     * @param item 項
     * @param by 要增加幾(大於0)
     * @return
     */
    public double hincr(String key, String item, double by) {
        return redisTemplate.opsForHash().increment(key, item, by);
    }
    /**
     * hash遞減
     * @param key 鍵
     * @param item 項
     * @param by 要減少記(小於0)
     * @return
     */
    public double hdecr(String key, String item, double by) {
        return redisTemplate.opsForHash().increment(key, item, -by);
    }
    // ============================set=============================
    /**
     * 根據key獲取Set中的所有值
     * @param key 鍵
     * @return
     */
    public Set<Object> sGet(String key) {
        try {
            return redisTemplate.opsForSet().members(key);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
    /**
     * 根據value從一個set中查詢,是否存在
     * @param key 鍵
     * @param value 值
     * @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;
        }
    }
    /**
     * 將數據放入set緩存
     * @param key 鍵
     * @param values 值 可以是多個
     * @return 成功個數
     */
    public long sSet(String key, Object... values) {
        try {
            return redisTemplate.opsForSet().add(key, values);
        } catch (Exception e) {
            e.printStackTrace();
            return 0;
        }
    }
    /**
     * 將set數據放入緩存
     * @param key 鍵
     * @param time 時間(秒)
     * @param values 值 可以是多個
     * @return 成功個數
     */
    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;
        }
    }
    /**
     * 獲取set緩存的長度
     * @param key 鍵
     * @return
     */
    public long sGetSetSize(String key) {
        try {
            return redisTemplate.opsForSet().size(key);
        } catch (Exception e) {
            e.printStackTrace();
            return 0;
        }
    }
    /**
     * 移除值為value的
     * @param key 鍵
     * @param values 值 可以是多個
     * @return 移除的個數
     */
    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=================================
    /**
     * 獲取list緩存的內容
     * @param key 鍵
     * @param start 開始
     * @param end 結束 0 到 -1代表所有值
     * @return
     */
    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;
        }
    }
    /**
     * 獲取list緩存的長度
     * @param key 鍵
     * @return
     */
    public long lGetListSize(String key) {
        try {
            return redisTemplate.opsForList().size(key);
        } catch (Exception e) {
            e.printStackTrace();
            return 0;
        }
    }
    /**
     * 通過索引 獲取list中的值
     * @param key 鍵
     * @param index 索引 index>=0時， 0 表頭，1 第二個元素，依次類推；index<0時，-1，表尾，-2倒數第二個元素，依次類推
     * @return
     */
    public Object lGetIndex(String key, long index) {
        try {
            return redisTemplate.opsForList().index(key, index);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
    /**
     * 將list放入緩存
     * @param key 鍵
     * @param value 值
     * @param time 時間(秒)
     * @return
     */
    public boolean lSet(String key, Object value) {
        try {
            redisTemplate.opsForList().rightPush(key, value);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
    /**
     * 將list放入緩存
     * @param key 鍵
     * @param value 值
     * @param time 時間(秒)
     * @return
     */
    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;
        }
    }
    /**
     * 將list放入緩存
     * @param key 鍵
     * @param value 值
     * @param time 時間(秒)
     * @return
     */
    public boolean lSet(String key, List<Object> value) {
        try {
            redisTemplate.opsForList().rightPushAll(key, value);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
    /**
     * 將list放入緩存
     * 
     * @param key 鍵
     * @param value 值
     * @param time 時間(秒)
     * @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;
        }
    }
    /**
     * 根據索引修改list中的某條數據
     * @param key 鍵
     * @param index 索引
     * @param value 值
     * @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個值為value
     * @param key 鍵
     * @param count 移除多少個
     * @param value 值
     * @return 移除的個數
     */
    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;
        }
    }
}

 

 

6、SpringBoot項目啟動時自動匹配Reids流程解析 

6.1）Spring Boot debug模式下的啟動log

SimpleCacheConfiguration:
Did not match:
- @ConditionalOnMissingBean (types: org.springframework.cache.CacheManager; SearchStrategy: all) found beans of type 'org.springframework.cache.CacheManager' cacheManager (OnBeanCondition)
Matched:
- Cache org.springframework.boot.autoconfigure.cache.SimpleCacheConfiguration automatic cache type (CacheCondition)

 

RedisAutoConfiguration matched:
- @ConditionalOnClass found required class 'org.springframework.data.redis.core.RedisOperations' (OnClassCondition)

RedisAutoConfiguration#redisTemplate matched:
- @ConditionalOnMissingBean (names: redisTemplate; SearchStrategy: all) did not find any beans (OnBeanCondition)

RedisAutoConfiguration#stringRedisTemplate matched:
- @ConditionalOnMissingBean (types: org.springframework.data.redis.core.StringRedisTemplate; SearchStrategy: all) did not find any beans (OnBeanCondition)

 

RedisCacheConfiguration   matched:
- @ConditionalOnClass found required class 'org.springframework.data.redis.connection.RedisConnectionFactory' (OnClassCondition)
- Cache org.springframework.boot.autoconfigure.cache.RedisCacheConfiguration automatic cache type (CacheCondition)
- @ConditionalOnBean (types: org.springframework.data.redis.connection.RedisConnectionFactory; SearchStrategy: all) found bean 'redisConnectionFactory'; @ConditionalOnMissingBean (types: org.springframework.cache.CacheManager; SearchStrategy: all) did not find any beans (OnBeanCondition)

 6.2) SpringBoot默認緩存配置類

@Configuration
@ConditionalOnMissingBean({CacheManager.class})
@Conditional({CacheCondition.class})
class SimpleCacheConfiguration { //SpringBoot的默認緩存 private final CacheProperties cacheProperties;
    private final CacheManagerCustomizers customizerInvoker;

    SimpleCacheConfiguration(CacheProperties cacheProperties, CacheManagerCustomizers customizerInvoker) {
        this.cacheProperties = cacheProperties;
        this.customizerInvoker = customizerInvoker;
    }

    @Bean
    public ConcurrentMapCacheManager cacheManager() {
        ConcurrentMapCacheManager cacheManager = new ConcurrentMapCacheManager();
        List<String> cacheNames = this.cacheProperties.getCacheNames();
        if (!cacheNames.isEmpty()) {
            cacheManager.setCacheNames(cacheNames);
        }

        return (ConcurrentMapCacheManager)this.customizerInvoker.customize(cacheManager);
    }
}

  

6.3) SpringBoot-Redis緩存配置類

　　當Spring Boot 引入Redis的依賴后，Redis的這個配置類就起作用了，RedisCacheManager即通過此配置文件被Spring裝載到Spring容器中，此時SimpleCacheConfiguration 自然就失效了，因為其類定義上標注着：@ConditionalOnMissingBean({CacheManager.class})

@Configuration
@ConditionalOnClass({RedisConnectionFactory.class})
@AutoConfigureAfter({RedisAutoConfiguration.class})
@ConditionalOnBean({RedisConnectionFactory.class})
@ConditionalOnMissingBean({CacheManager.class}) //當容器中沒有CacheManager的時候生效
@Conditional({CacheCondition.class})
class RedisCacheConfiguration {
    private final CacheProperties cacheProperties;
    private final CacheManagerCustomizers customizerInvoker;
    private final org.springframework.data.redis.cache.RedisCacheConfiguration redisCacheConfiguration;

    RedisCacheConfiguration(CacheProperties cacheProperties, CacheManagerCustomizers customizerInvoker, ObjectProvider<org.springframework.data.redis.cache.RedisCacheConfiguration> redisCacheConfiguration) {
        this.cacheProperties = cacheProperties;
        this.customizerInvoker = customizerInvoker;
        this.redisCacheConfiguration = (org.springframework.data.redis.cache.RedisCacheConfiguration)redisCacheConfiguration.getIfAvailable();
    }
　　
 
 //向Spring容器中放入了一個定制的RedisCacheManager,正是它導致了SpringBoot默認緩存配置類：SimpleCacheConfiguration失效
    @Bean
    public RedisCacheManager cacheManager(RedisConnectionFactory redisConnectionFactory, ResourceLoader resourceLoader) {
        RedisCacheManagerBuilder builder = RedisCacheManager.builder(redisConnectionFactory).cacheDefaults(this.determineConfiguration(resourceLoader.getClassLoader()));
        List<String> cacheNames = this.cacheProperties.getCacheNames();
        if (!cacheNames.isEmpty()) {
            builder.initialCacheNames(new LinkedHashSet(cacheNames));
        }

        return (RedisCacheManager)this.customizerInvoker.customize(builder.build());
    }

    private org.springframework.data.redis.cache.RedisCacheConfiguration determineConfiguration(ClassLoader classLoader) {
        if (this.redisCacheConfiguration != null) {
            return this.redisCacheConfiguration;
        } else {
            Redis redisProperties = this.cacheProperties.getRedis();
            org.springframework.data.redis.cache.RedisCacheConfiguration config = org.springframework.data.redis.cache.RedisCacheConfiguration.defaultCacheConfig();
            config = config.serializeValuesWith(SerializationPair.fromSerializer(new JdkSerializationRedisSerializer(classLoader)));
            if (redisProperties.getTimeToLive() != null) {
                config = config.entryTtl(redisProperties.getTimeToLive());
            }

            if (redisProperties.getKeyPrefix() != null) {
                config = config.prefixKeysWith(redisProperties.getKeyPrefix());
            }

            if (!redisProperties.isCacheNullValues()) {
                config = config.disableCachingNullValues();
            }

            if (!redisProperties.isUseKeyPrefix()) {
                config = config.disableKeyPrefix();
            }

            return config;
        }
    }
}

 

7、自定義緩存管理器（Redis緩存配置類會失效嗎？？？）

　　/**
     * 自定義緩存管理器
     * @param redisConnectionFactory
     * @param resourceLoader
     * @return
     */
    @Bean
    public RedisCacheManager cacheManager(RedisConnectionFactory redisConnectionFactory, ResourceLoader resourceLoader) {
        //redis加鎖的寫入器
        RedisCacheWriter writer = RedisCacheWriter.lockingRedisCacheWriter(redisConnectionFactory);


        //啟動Redis緩存的默認設置
        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig(resourceLoader.getClassLoader());
        //設置JDK序列化器
        config = config.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(new Jackson2JsonRedisSerializer(User.class)));

        //禁用前綴
        config = config.disableKeyPrefix();

        //設置10 min 超時
        config = config.entryTtl(Duration.ofMinutes(10));

        
        RedisCacheManager redisCacheManager = new RedisCacheManager(writer,config);

        return redisCacheManager;
    }