1. SpringCache实战遇坑
1.1. pom
- 主要是以下两个
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<!-- 配合redis做缓存 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-cache</artifactId>
</dependency>
1.2. Redis配置
package com.zhiyis.common.config;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
import redis.clients.jedis.JedisPoolConfig;
import java.lang.reflect.Method;
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {
private static Logger logger = LoggerFactory.getLogger(RedisConfig.class);
@Value("${spring.redis.host}")
private String redisHost;
@Value("${spring.redis.port}")
private int redisPort;
@Value("${spring.redis.timeout}")
private int redisTimeout;
@Value("${spring.redis.password}")
private String redisAuth;
@Value("${spring.redis.database}")
private int redisDb;
@Value("${spring.redis.pool.max-active}")
private int maxActive;
@Value("${spring.redis.pool.max-wait}")
private int maxWait;
@Value("${spring.redis.pool.max-idle}")
private int maxIdle;
@Value("${spring.redis.pool.min-idle}")
private int minIdle;
@Bean
@Override
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();
}
};
}
@Bean
public CacheManager redisCacheManager() {
RedisCacheManager cacheManager = new RedisCacheManager(redisTemplate());
//默认300秒过期
cacheManager.setDefaultExpiration(300);
// 启动时加载远程缓存
cacheManager.setLoadRemoteCachesOnStartup(true);
//是否使用前缀生成器
cacheManager.setUsePrefix(true);
return cacheManager;
}
@Bean
public RedisConnectionFactory redisConnectionFactory() {
JedisPoolConfig poolConfig = new JedisPoolConfig();
poolConfig.setMaxTotal(maxActive);
poolConfig.setMaxIdle(maxIdle);
poolConfig.setMaxWaitMillis(maxWait);
poolConfig.setMinIdle(minIdle);
poolConfig.setTestOnBorrow(true);
poolConfig.setTestOnReturn(false);
poolConfig.setTestWhileIdle(true);
JedisConnectionFactory jedisConnectionFactory = new JedisConnectionFactory(poolConfig);
jedisConnectionFactory.setPassword(redisAuth);
jedisConnectionFactory.setHostName(redisHost);
jedisConnectionFactory.setDatabase(redisDb);
jedisConnectionFactory.setPort(redisPort);
jedisConnectionFactory.setTimeout(redisTimeout);
return jedisConnectionFactory;
}
@Bean
public RedisTemplate<String, Object> redisTemplate() {
RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
Jackson2JsonRedisSerializer<Object> serializer = jackson2JsonRedisSerializer();
redisTemplate.setConnectionFactory(redisConnectionFactory());
redisTemplate.setKeySerializer(new StringRedisSerializer());
redisTemplate.setValueSerializer(serializer);
redisTemplate.setHashKeySerializer(new StringRedisSerializer());
redisTemplate.setHashValueSerializer(serializer);
return redisTemplate;
}
@Bean
public Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer() {
final Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
final ObjectMapper objectMapper = Jackson2ObjectMapperBuilder
.json().build();
objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
return jackson2JsonRedisSerializer;
}
}
在application.properties填上相应的参数
1.3. 使用
1.3.1. 坑1
- 目前主要使用的就是缓存和删除缓存
@Cacheable(sync = true, value = "on_hospital_list", key = "\'3003101006_\'+#requestReport.body[\'carer_id\']", condition = "#requestReport.body[\'carer_id\'] != \'\' ")
@Override
public ResponseReport getHospitalList(RequestReport requestReport) {
ResponseReport responseReport = new ResponseReport();
。。。
return responseReport.returnSuccessResult(hospitals, "获取医院列表成功", requestReport);
}
- 这里没有经验的人可能会纠结很久，因为我封装的入参对象，里面放的是JSONObject或者map作为的body值，这里我一开始是写成requestReport.body.carer_id这样的，但是这样会报如下错误
EL1008E: object of type \'com.alibaba.fastjson.JSONObject\' - maybe not public
但你在网上找答案，都是文不对题，或者说其他错误导致相同的报错，反正我是找不到正确的解答
3. 解决方法就是如上代码，直接写成#requestReport.body[\'carer_id\']
1.3.2. 坑2
- 删除缓存，我自定义了一个注解，原因是好像CacheEvict没提供删除多个key的方法
// @CacheEvict(value = "on_hospital_list", key="\'3003101006_\'+#requestReport.body[\'carer_id\']")
@CacheRemove(value = "on_hospital_list"/*,key={"\'3003101006_\'+#requestReport.body[\'carer_id\']","\'3003101007_\'+#requestReport.body[\'carer_id\']"}*/)
@Override
public ResponseReport upDownServer(RequestReport requestReport) {
。。。业务逻辑
return responseReport.returnError("9999", "上下线失败", requestReport);
}
- 注解
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface CacheRemove {
/**
* 需要清除的大类 例如 autocms 所有缓存
*
* @return
*/
String value() default "";
/**
* 需要清除的具体的额类型
*
* @return
*/
String[] key() default {};
}
- 注解实现
import com.zhiyis.framework.annotation.CacheRemove;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;
/**
* 清除缓存切面类
*
* @author laoliangliang
* @date 2019/1/14 16:04
*/
@Component
@Aspect
public class CacheRemoveAspect {
Logger logger = LoggerFactory.getLogger(this.getClass());
@Autowired
RedisTemplate<String, String> redis;
ExpressionParser parser = new SpelExpressionParser();
LocalVariableTableParameterNameDiscoverer discoverer = new LocalVariableTableParameterNameDiscoverer();
/**
* 截获标有@CacheRemove的方法
*/
@Pointcut(value = "(execution(* *.*(..)) && @annotation(com.zhiyis.framework.annotation.CacheRemove))")
private void pointcut() {
}
/**
* 功能描述: 切面在截获方法返回值之后
*/
@AfterReturning(value = "pointcut()")
private void process(JoinPoint joinPoint) {
Object[] args = joinPoint.getArgs();
//获取切入方法的数据
MethodSignature signature = (MethodSignature) joinPoint.getSignature();
//获取切入方法
Method method = signature.getMethod();
//获得注解
CacheRemove cacheRemove = method.getAnnotation(CacheRemove.class);
//注解解析
String[] params = discoverer.getParameterNames(method);
EvaluationContext context = new StandardEvaluationContext();
for (int len = 0; len < params.length; len++) {
context.setVariable(params[len], args[len]);
}
if (cacheRemove != null) {
StringBuilder sb = new StringBuilder();
String value = cacheRemove.value();
if (!value.equals("")) {
sb.append(value);
}
//需要移除的正则key
String[] keys = cacheRemove.key();
sb.append(":");
for (String key : keys) {
Expression expression = parser.parseExpression(key);
String value1 = expression.getValue(context, String.class);
//指定清除的key的缓存
cleanRedisCache(sb.toString() + value1);
}
}
}
private void cleanRedisCache(String key) {
if (key != null) {
//删除缓存
redis.delete(key);
logger.info("清除 " + key + " 缓存");
}
}
}
- 这里的注解写入参数，如果想要使用spel表达式，要写上解析注解的一段代码
参考