原文:http://www.ityouknow.com/springboot/2016/03/06/spring-boot-redis.html
https://blog.csdn.net/plei_yue/article/details/79362372
jar包版本:
jedis-2.9.0.jar
commons-pool2-2.4.3.jar
spring-*-3.24.jar
如何使用
1、引入 spring-boot-starter-redis
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-redis</artifactId>
</dependency>
2、添加配置文件
# REDIS (RedisProperties)
# Redis数据库索引(默认为0)
spring.redis.database=0
# Redis服务器地址
spring.redis.host=192.168.0.58
# Redis服务器连接端口
spring.redis.port=6379
# Redis服务器连接密码(默认为空)
spring.redis.password=
# 连接池最大连接数(使用负值表示没有限制)
spring.redis.pool.max-active=8
# 连接池最大阻塞等待时间(使用负值表示没有限制)
spring.redis.pool.max-wait=-1
# 连接池中的最大空闲连接
spring.redis.pool.max-idle=8
# 连接池中的最小空闲连接
spring.redis.pool.min-idle=0
# 连接超时时间(毫秒)
spring.redis.timeout=0
3、添加cache的配置类
StringRedisTemplate默认采用的key序列化方式为setKeySerializer(stringSerializer);此时在使用Spring的缓存注解如@Cacheable的key属性设置值时,就需
要注意如果参数类型为Long那么会出不能进行String类型转换异常。
RedisTemplate默认使用的序列化方式为JdkSerializationRedisSerializer,它就没有上边的问题。因为它的序列化方法为serialize(Object object)
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport{
@Bean
public KeyGenerator keyGenerator() {
return new KeyGenerator() {
@Override
public Object generate(Object target, Method method, Object... params) {
StringBuilder sb = new StringBuilder();
sb.append(target.getClass().getName());
sb.append(method.getName());
for (Object obj : params) {
sb.append(obj.toString());
}
return sb.toString();
}
};
}
@SuppressWarnings("rawtypes")
@Bean
public CacheManager cacheManager(RedisTemplate redisTemplate) {
RedisCacheManager rcm = new RedisCacheManager(redisTemplate);
//设置缓存过期时间
//rcm.setDefaultExpiration(60);//秒
return rcm;
}
@Bean
public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory factory) {
StringRedisTemplate template = new StringRedisTemplate(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);
template.setValueSerializer(jackson2JsonRedisSerializer);
template.afterPropertiesSet();
return template;
}
}
如果你只需要使用基本的redis配置,那么使用如下配置类即可,spring boot会自动扫描redis的基本配置,但是有一项要注意那就是password,如果你在配置文件中设置了password,那么就必须在配置类中手工注入JedisConnectionFactory中,否则会在启动过程中报NOAUTH Authentication required.;:
@Bean public JedisConnectionFactory redisConnectionFactory() { JedisConnectionFactory factory = new JedisConnectionFactory(); factory.setHostName(host); factory.setPort(port); factory.setPassword(password); factory.setTimeout(timeout); //设置连接超时时间 //连接池配置 JedisPoolConfig poolConfig = new JedisPoolConfig(); poolConfig.setMinIdle(minIdle); poolConfig.setMaxIdle(maxIdle); poolConfig.setMaxTotal(maxTotal); poolConfig.setMaxWaitMillis(maxWait); factory.setPoolConfig(poolConfig); return factory; }
JedisPoolConfig config = new JedisPoolConfig(); //连接耗尽时是否阻塞, false报异常,ture阻塞直到超时, 默认true config.setBlockWhenExhausted(true); //设置的逐出策略类名, 默认DefaultEvictionPolicy(当连接超过最大空闲时间,或连接数超过最大空闲连接数) config.setEvictionPolicyClassName("org.apache.commons.pool2.impl.DefaultEvictionPolicy"); //是否启用pool的jmx管理功能, 默认true config.setJmxEnabled(true); //MBean ObjectName = new ObjectName("org.apache.commons.pool2:type=GenericObjectPool,name=" + "pool" + i); 默 认为"pool", JMX不熟,具体不知道是干啥的...默认就好. config.setJmxNamePrefix("pool"); //是否启用后进先出, 默认true config.setLifo(true); //最大空闲连接数, 默认8个 config.setMaxIdle(8); //最大连接数, 默认8个 config.setMaxTotal(8); //获取连接时的最大等待毫秒数(如果设置为阻塞时BlockWhenExhausted),如果超时就抛异常, 小于零:阻塞不确定的时间, 默认-1 config.setMaxWaitMillis(-1); //逐出连接的最小空闲时间 默认1800000毫秒(30分钟) config.setMinEvictableIdleTimeMillis(1800000); //最小空闲连接数, 默认0 config.setMinIdle(0); //每次逐出检查时 逐出的最大数目 如果为负数就是 : 1/abs(n), 默认3 config.setNumTestsPerEvictionRun(3); //对象空闲多久后逐出, 当空闲时间>该值 且 空闲连接>最大空闲数 时直接逐出,不再根据MinEvictableIdleTimeMillis判断 (默认逐出策略) config.setSoftMinEvictableIdleTimeMillis(1800000); //在获取连接的时候检查有效性, 默认false config.setTestOnBorrow(false); //在空闲时检查有效性, 默认false config.setTestWhileIdle(false); //逐出扫描的时间间隔(毫秒) 如果为负数,则不运行逐出线程, 默认-1 config.setTimeBetweenEvictionRunsMillis(-1);
3、好了,接下来就可以直接使用了,测试
@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(Application.class)
public class TestRedis {
@Autowired
private StringRedisTemplate stringRedisTemplate;
@Autowired
private RedisTemplate redisTemplate;
@Test
public void test() throws Exception {
stringRedisTemplate.opsForValue().set("aaa", "111");
Assert.assertEquals("111", stringRedisTemplate.opsForValue().get("aaa"));
}
@Test
public void testObj() throws Exception {
User user=new User("aa@126.com", "aa", "aa123456", "aa","123");
ValueOperations<String, User> operations=redisTemplate.opsForValue();
operations.set("com.neox", user);
operations.set("com.neo.f", user,1,TimeUnit.SECONDS);
Thread.sleep(1000);
//redisTemplate.delete("com.neo.f");
boolean exists=redisTemplate.hasKey("com.neo.f");
if(exists){
System.out.println("exists is true");
}else{
System.out.println("exists is false");
}
// Assert.assertEquals("aa", operations.get("com.neo.f").getUserName());
}
}
以上都是手动使用的方式,如何在查找数据库的时候自动使用缓存呢,看下面;
4、自动根据方法生成缓存
@RequestMapping("/getUser")
@Cacheable(value="user-key")
public User getUser() {
User user=userRepository.findByUserName("aa");
System.out.println("若下面没出现“无缓存的时候调用”字样且能打印出数据表示测试成功");
return user;
}
其中value的值就是缓存到redis中的key
5.序列化,反序列化
springData还提供了其他的序列化方式,如下:
GenericJackson2JsonRedisSerializer.class GenericToStringSerializer.class Jackson2JsonRedisSerializer.class JacksonJsonRedisSerializer.class JdkSerializationRedisSerializer.class OxmSerializer.class RedisSerializer.class SerializationException.class SerializationUtils.class StringRedisSerializer.class
GenericToStringSerializer:使用Spring转换服务进行序列化;
JacksonJsonRedisSerializer:使用Jackson 1,将对象序列化为JSON;
Jackson2JsonRedisSerializer:使用Jackson 2,将对象序列化为JSON;
JdkSerializationRedisSerializer:使用Java序列化;
OxmSerializer:使用Spring O/X映射的编排器和解排器(marshaler和unmarshaler)实现序列化,用于XML序列化;
StringRedisSerializer:序列化String类型的key和value。实际上是String和byte数组之间的转换
6. 遇到的报错:
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.data.redis.core.RedisTemplate<?, ?>' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {} at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1486) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1104) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] ... 43 common frames omitted