SpringCache注解实现自定义失效时间(升级版)

SpringCache注解实现自定义失效时间

SpringCache Redis提供了开箱即用的缓存功能,但是美中不足的是官方只支持全部失效时间配置,在项目中我们可能需要对某一些接口针对性的配置失效时间,此时就需要自己来定制了。在此之前的项目中我实现过两种方式来解决该问题,但是粒度只能到类级别,同时配置也有一些不太合理的地方,这次做了优化,并且在公司的生产环境稳定运行了半年有余暂时还没发现问题,本着开源共享的精神,分享出来,本人代码能力有限,如果问题还望各位看官大佬多多包涵。

关于旧版本的实现参考这里

原理

通过获取方法前的注解值,比如:@CacheExpire(ttl = 10, unit = TimeUnit.SECONDS) 得到配置的失效时间,因为我是通过一个map来存放某个方法以及对应的失效时间,map的泛型是 Map<String, Duration> 其中key是当前方法对应的缓存key,为了保证该key全局唯一,用spring cache自己的方式不太可行,所以在项目启动之前动态修改注解的值,动态添加keyGenerator 为自定义的key生成器作为key。

举个例子:

启动前FooService.java

@CacheExpire(ttl = 1, unit = TimeUnit.MINUTES)
@Service
public class FooService { 

    @CacheExpire(ttl = 10, unit = TimeUnit.SECONDS)
	@Cacheable
	public Map<String,String> foo() {
		Map<String,String> map = new HashMap<String, String>();
		map.put("k1", "v1");
		return map;
	}
  
}

启动后经过自定义的代码处理会变成:

@CacheExpire(ttl = 1, unit = TimeUnit.MINUTES)
@Service
public class FooService { 

  // myKeyGenerator 是自定义的key生成器
  // cacheNames 就是动态添加的值,规则是 全类名.方法明 
  @CacheExpire(ttl = 10, unit = TimeUnit.SECONDS)
  @Cacheable(keyGenerator="myKeyGenerator", cacheNames="com.bart.service.FooService.foo") 
  public Map<String,String> foo() {
    Map<String,String> map = new HashMap<String, String>();
    map.put("k1", "v1");
    return map;
  }
  
}

最终 Map<String, Duration> 里面存放的就是

{
 "com.bart.service.FooService.foo" = PTS10 
}

在spring cache 往 redis 中put值的时候调用我重写的逻辑,拿到当前方法的cacheNamesMap<String, Duration> 取对应的失效时间从而实现了方法级别的粒度控制。

步骤

依赖

<project xmlns="http://maven.apache.org/POM/4.0.0"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

	<modelVersion>4.0.0</modelVersion>
	<groupId>com.bart.springboot</groupId>
	<artifactId>springboot-cache</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<!-- 配置编译版本和编码格式 -->
	<properties>
		<maven.compiler.encoding>UTF-8</maven.compiler.encoding>
		<maven.compiler.target>1.8</maven.compiler.target>
		<maven.compiler.source>1.8</maven.compiler.source>
		<commons-pool.version>1.6</commons-pool.version>
		<skipTests>true</skipTests>
	</properties>

	<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
        <relativePath/>
    </parent>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		
		<!-- spring boot 的缓存 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-cache</artifactId>
        </dependency>
		
		<!-- 引入Redis得启动器 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

        <!--
            再Spring2.X版本中使用Redis需要引入该依赖
            1.X版本则不需要
        -->
        <dependency>
            <groupId>commons-pool</groupId>
            <artifactId>commons-pool</artifactId>
            <version>${commons-pool.version}</version>
        </dependency>
		
		 <!-- jedis -->
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>3.0.0</version>
        </dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-configuration-processor</artifactId>
			<optional>true</optional>
		</dependency>

		<dependency>
			<groupId>cn.hutool</groupId>
			<artifactId>hutool-all</artifactId>
			<version>5.4.1</version>
		</dependency>

		<dependency>
			<groupId>com.alibaba</groupId>
			<artifactId>fastjson</artifactId>
			<version>1.2.9</version>
		</dependency>

	</dependencies>

	<!-- Package as an executable jar -->
	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>			
		</plugins>
	</build>

</project>

配置文件

server:
  port: 8888

spring:
  profiles: dev
  redis:
    database: 0
    host: 127.0.0.1
    port: 6379
    password: 
    timeout: 10000 #连接超时时间
    lettuce: 
      pool: 
        #最大连接数
        max-active: 8
        #最大阻塞等待时间(负数表示没限制)
        max-wait: 0
        #最大空闲
        max-idle: 8
        #最小空闲
        min-idle: 0

自定义类

注解


import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.concurrent.TimeUnit;

/**
 * 缓存失效的注解
 */
@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface CacheExpire {

    /**
     * 失效时间,默认是60
     * @return
     */
    public long ttl() default 60L;

    /**
     * 单位,默认是秒
     * @return
     */
    public TimeUnit unit() default TimeUnit.SECONDS;
}

自定义key生成器


import com.alibaba.fastjson.JSON;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import java.lang.reflect.Method;

/**
 * Created by BartG on 2019/1/23.
 * 自定义的缓存key生成器
 */
@Component("myCacheKeyGenerator")
public class MyCacheKeyGenerator implements KeyGenerator {

    Logger logger = LoggerFactory.getLogger(MyCacheKeyGenerator.class);

    private final static String SEPARATE = ":";

    @Override
    public Object generate(Object target, Method method, Object... params) {
        String className = target.getClass().getName();
        String methodName = method.getName();
        String paramNames = "";
        if(null != params) {
            paramNames = JSON.toJSONString(params);
        }
        String key = generate(className, methodName, paramNames);
        logger.info("generate -> "+ key);
        return key;
    }

    public static String generate(String clsName, String methodName, String params) {
        StringBuilder sb = new StringBuilder();
        sb.append(clsName);
        sb.append(SEPARATE);
        sb.append(methodName);
        if(!StringUtils.isEmpty(params)) {
            sb.append(SEPARATE);
            sb.append(params);
        }
        return sb.toString();
    }
}

自定义RedisCacheManager


import org.springframework.data.redis.cache.CacheKeyPrefix;
import org.springframework.data.redis.cache.RedisCache;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.cache.RedisCacheWriter;

import java.time.Duration;
import java.util.HashMap;
import java.util.Map;

public class RedisCacheManagerCustomize extends RedisCacheManager {

	private final static String PREFIX = "bart:spring:cache:";
	
	public final static CacheKeyPrefix cacheKeyPrefix = new CacheKeyPrefix() {

		@Override
		public String compute(String cacheName) {
			return PREFIX;
		}
		
	};
	
    protected final static Map<String, Duration> CACHE_NAME_MAP = new HashMap<>();

    public RedisCacheManagerCustomize(RedisCacheWriter cacheWriter, RedisCacheConfiguration defaultCacheConfiguration) {
        super(cacheWriter, defaultCacheConfiguration);
    }

    @Override
    protected RedisCache createRedisCache(String name, RedisCacheConfiguration cacheConfig) {
        return super.createRedisCache(name, copyCacheConfiguration(name, cacheConfig));
    }

    protected RedisCacheConfiguration copyCacheConfiguration(String name, RedisCacheConfiguration cacheConfig) {
        if(null != cacheConfig) {
            if(CACHE_NAME_MAP.containsKey(name)) {
                RedisCacheConfiguration redisCacheConfigurationCopy = cacheConfig.entryTtl(CACHE_NAME_MAP.get(name))
                		.computePrefixWith(RedisCacheManagerCustomize.cacheKeyPrefix);
                return redisCacheConfigurationCopy;
            }
        }
        return cacheConfig;
    }

}

动态修改注解的值

什么要放到 BeanDefinitionRegistryPostProcessor 中去处理,因为此时所有的bean已经被spring扫描但是还未被初始化,正好适合修改注解的值,如果放到BeanPostProcessor 中的话类可能已经被初始化了,此时修改注解无效,这里具体的原因要追踪spring源码。


import com.alibaba.fastjson.JSON;
import com.spboot.config.cache.helper.CacheExpire;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.BeanDefinitionRegistryPostProcessor;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.CacheConfig;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.stereotype.Component;
import org.springframework.util.Assert;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.time.Duration;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;

/**
 * 在Bean创建之前动态修改注解的值
 *
 * 调用栈(由下到上):
 * org.springframework.context.support.PostProcessorRegistrationDelegate#invokeBeanDefinitionRegistryPostProcessors(java.util.Collection, org.springframework.beans.factory.support.BeanDefinitionRegistry)
 * org.springframework.beans.factory.support.BeanDefinitionRegistryPostProcessor#postProcessBeanDefinitionRegistry(org.springframework.beans.factory.support.BeanDefinitionRegistry)
 * org.springframework.context.support.PostProcessorRegistrationDelegate#invokeBeanFactoryPostProcessors(org.springframework.beans.factory.config.ConfigurableListableBeanFactory, java.util.List)
 * org.springframework.context.support.AbstractApplicationContext#refresh()
 */
@Component
public class AnnotationInjectProcessor implements BeanDefinitionRegistryPostProcessor {

    protected final static Logger logger = LoggerFactory.getLogger(AnnotationInjectProcessor.class);

    private String keyGeneratorName = "";

    @Override
    public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
        // 需要处理的包名,只需要处理当前项目扫描路径和 @SpringBootApplication 配置的 scanBasePackages
    	List<String> projectScanPackageNames = new ArrayList<>();
        String mainClassName = null; // 入口类名、
        // 参考代码: org.springframework.boot.SpringApplication.deduceMainApplicationClass
        StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
        for (StackTraceElement stackTraceElement : stackTraceElements) {
            if("main".equals(stackTraceElement.getMethodName())) {
                mainClassName = stackTraceElement.getClassName();
                break;
            }
        }
        Assert.notNull(mainClassName, "未找到入口类,程序异常!");
        String basePackageName = mainClassName.substring(0, mainClassName.lastIndexOf(".")); // 当前项目包名
        projectScanPackageNames.add(basePackageName);
        try {
            Class<?> mainClass = Class.forName(mainClassName);
            SpringBootApplication springBootApplication = mainClass.getAnnotation(SpringBootApplication.class);
            String[] scanBasePackages = springBootApplication.scanBasePackages();
            if(null != scanBasePackages && scanBasePackages.length > 0) {
                projectScanPackageNames.addAll(Arrays.asList(scanBasePackages));
            }
        } catch (Exception e) {
            logger.info("get main class err, class = {}, reason = ", mainClassName, e);
        }
        String[] beanDefinitionNames = registry.getBeanDefinitionNames();
        // 找到自定义的key generator
        List<Class<?>> prepareToInjectList = new ArrayList<>(beanDefinitionNames.length);
        for (String beanDefinitionName : beanDefinitionNames) {
            BeanDefinition beanDefinition = registry.getBeanDefinition(beanDefinitionName);
            String beanClassName = beanDefinition.getBeanClassName();
            try {
                // 如果为空或者当前类就跳过
                if(StringUtils.isEmpty(beanClassName) || this.getClass().getName().equals(beanClassName)) {
                    continue;
                }
                Class<?> cls = Class.forName(beanClassName);
                if(KeyGenerator.class.isAssignableFrom(cls)) {
                    keyGeneratorName = beanDefinitionName;
                }
                for (String scanPackageName : projectScanPackageNames) {
                    if(beanClassName.startsWith(scanPackageName)) {
                        prepareToInjectList.add(cls);
                        break;
                    }
                }
            }catch (Exception e) {
                logger.error("can not load class = {}, reason: {}", beanClassName, e);
            }
        }
        // 当前环境必须有一个key generator 否则报错
        Assert.isTrue(!StringUtils.isEmpty(keyGeneratorName),
                "current ioc environment must have one org.springframework.cache.interceptor.KeyGenerator instance!");
        // 开始修改注解的值
        for (Class<?> cls : prepareToInjectList) {
            injectAnnotationValue(cls, keyGeneratorName );
        }
    }

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
    	
    }
    
    /**
     * 修改当前类的 @Cacheable 、@CachePut 注解的属性值
     * @param cls
     */
    protected static void injectAnnotationValue(Class<?> cls, String keyGeneratorName) {
        CacheConfig cacheConfig = cls.getAnnotation(CacheConfig.class);
        if(null != cacheConfig && cacheConfig.cacheNames().length > 0 && !StringUtils.isEmpty(cacheConfig.keyGenerator())) {
            CacheExpire cacheExpire = cls.getAnnotation(CacheExpire.class);
            if(null != cacheExpire) {
                RedisCacheManagerCustomize.CACHE_NAME_MAP.put(cacheConfig.cacheNames()[0], Duration.ofSeconds(cacheExpire.unit().toSeconds(cacheExpire.ttl())));
            }
            return; // 如果当前类通过@CacheConfig指定了cacheNames、kenGenerator就不处理
        }
        Method[] declaredMethods = cls.getDeclaredMethods();
        for (Method method : declaredMethods) {
            InvocationHandler handler = null ;
            try {
                Object annotation = method.getAnnotation(Cacheable.class);
                if(null == annotation) {
                    annotation = method.getAnnotation(CachePut.class);
                }
                if(null == annotation) {
                    annotation = method.getAnnotation(CacheEvict.class);
                }
                if(null == annotation) {
                    return;
                }
                handler = Proxy.getInvocationHandler(annotation);
                if(null != handler) {
                    injectAnnotationValue(cls, method, handler, keyGeneratorName);
                }
            } catch (Exception e) {
                logger.error("inject error : class=[{}] , method=[{}]  ! reason : {}", cls.getName(), method.getName(), e);
            }
        }
    }

    protected static void injectAnnotationValue(Class<?> cls, Method method ,InvocationHandler handler,  String keyGeneratorName) throws Exception {
        // 获取 AnnotationInvocationHandler 的 memberValues 字段
        Field typeField = handler.getClass().getDeclaredField("type");
        ReflectionUtils.makeAccessible(typeField);
        String annotationTypeName = ((Class<? extends Annotation>)typeField.get(handler)).getName();
        Field memberValuesField = handler.getClass().getDeclaredField("memberValues");
        ReflectionUtils.makeAccessible(memberValuesField);
        Map<String, Object> memberValues = (Map<String, Object>)memberValuesField.get(handler);
        logger.debug("inject start class=[{}] , method=[{}], annotation=[{}] , memberValues={}", cls.getName(), method.getName(), annotationTypeName, JSON.toJSONString(memberValues));
        String[] cacheNames = (String[])memberValues.get("cacheNames");
        String generateKey = MyCacheKeyGenerator.generate(cls.getName(), method.getName(), "");
        if(cacheNames.length == 0) {
            memberValues.put("cacheNames", new String[]{generateKey});
        }
        String keyGenerator = (String)memberValues.get("keyGenerator");
        // 指定的key和keyGenerator会冲突,所以判断一下不能影响框架之前的逻辑
        if(StringUtils.isEmpty(memberValues.get("key")) && StringUtils.isEmpty(keyGenerator) ) {
            memberValues.put("keyGenerator", keyGeneratorName);
        }
        // 获得@CacheExpire注解解析失效时间
        CacheExpire cacheExpire = method.getAnnotation(CacheExpire.class);
        if(null == cacheExpire) {
            // 方法未添加就取当前类的注解
            cacheExpire = cls.getAnnotation(CacheExpire.class);
        }
        if(null != cacheExpire) {
            RedisCacheManagerCustomize.CACHE_NAME_MAP.put(generateKey, Duration.ofSeconds(cacheExpire.unit().toSeconds(cacheExpire.ttl())));
        }
        logger.debug("inject end class=[{}] , method=[{}], annotation=[{}] , memberValues={}", cls.getName(), method.getName(), annotationTypeName, JSON.toJSONString(memberValues));
    }

}

配置类


import java.time.Duration;
import java.time.LocalDate;
import java.time.LocalDateTime;

import com.fasterxml.jackson.databind.module.SimpleModule;
import com.spboot.config.mvc.JsonConverters;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.cache.RedisCacheWriter;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
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
@EnableCaching // 开启spring的缓存
public class CacheConfig {

    

    /**
     * 自定义得缓存管理器
     * @param redisConnectionFactory
     * @return
     */
    @Primary
    @Bean
    public RedisCacheManager cacheManager(RedisConnectionFactory redisConnectionFactory) {
        //初始化一个RedisCacheWriter
        RedisCacheWriter redisCacheWriter = RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory);
        // key 序列化方式
        StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
        // value的序列化机制
        Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = jackson2JsonRedisSerializer();
        // 配置
        RedisCacheConfiguration defaultCacheConfig = RedisCacheConfiguration.defaultCacheConfig()
                .entryTtl(Duration.ofHours(1))
                .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(stringRedisSerializer))  // 设置 k v 序列化机制
                .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
                .computePrefixWith(RedisCacheManagerCustomize.cacheKeyPrefix);
        //初始化RedisCacheManager
//        RedisCacheManager cacheManager = new RedisCacheManager(redisCacheWriter, defaultCacheConfig);
        RedisCacheManager cacheManager = new RedisCacheManagerCustomize(redisCacheWriter, defaultCacheConfig);
        return cacheManager;
    }
    
    Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer() {
        Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        SimpleModule module = new SimpleModule();
        // 添加对自定义日期类型解析的解析器
        module.addSerializer(LocalDateTime.class, JsonConverters.localDateTimeSerializer());
        module.addDeserializer(LocalDateTime.class, JsonConverters.localDateTimeDeserializer());
        module.addSerializer(LocalDate.class, JsonConverters.localDateSerializer());
        module.addDeserializer(LocalDate.class, JsonConverters.localDateDeserializer());
        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
        return jackson2JsonRedisSerializer;
    }


}

JSON序列化器


import java.io.IOException;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.deser.std.StringDeserializer;


public class JsonConverters {

	final static DateTimeFormatter DTF_LOCADATETIME = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss", Locale.CHINA);
	final static DateTimeFormatter DTF_LOCADATE = DateTimeFormatter.ofPattern("yyyy-MM-dd", Locale.CHINA);

	public static JsonDeserializer<LocalDate> localDateDeserializer() {
		return new JsonDeserializer<LocalDate>() {
			@Override
			public LocalDate deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
				String result = StringDeserializer.instance.deserialize(p, ctxt);
				System.out.println("LocalDateTimeJsonDeserializer -> "+ result);
				return LocalDate.parse(result, DTF_LOCADATE);
			}
		};
	}
	
	public static JsonSerializer<LocalDate> localDateSerializer() {
		return new JsonSerializer<LocalDate>() {
			@Override
			public void serialize(LocalDate value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
				String format = DTF_LOCADATE.format(value);
				System.out.println("LocalDateTimeJsonSerializer -> "+ format);
				gen.writeString(format);
//			gen.writeNumber(value.toInstant(ZoneOffset.of("+8")).toEpochMilli());
			}
		};
	}

	public static JsonDeserializer<LocalDateTime> localDateTimeDeserializer() {
		return new JsonDeserializer<LocalDateTime>() {
			@Override
			public LocalDateTime deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
				String result = StringDeserializer.instance.deserialize(p, ctxt);
				System.out.println("LocalDateTimeJsonDeserializer -> "+ result);
				return LocalDateTime.parse(result, DTF_LOCADATETIME);
			}
		};
	}

	public static JsonSerializer<LocalDateTime> localDateTimeSerializer() {
		return new JsonSerializer<LocalDateTime>() {
			@Override
			public void serialize(LocalDateTime value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
				String format = DTF_LOCADATETIME.format(value);
				System.out.println("LocalDateTimeJsonSerializer -> "+ format);
				gen.writeString(format);
//			gen.writeNumber(value.toInstant(ZoneOffset.of("+8")).toEpochMilli());
			}
		};
	}
}

测试类

controller


import java.util.HashMap;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api")
public class TestApiController {

	@Autowired
	TestApiService testApiService;
	
    // 使用全局缓存命名空间
	@GetMapping("/v10")
	public ResponseEntity v10() {
		System.err.println("线程 = "+ Thread.currentThread().getId());
		System.err.println("类加载器 = "+ this.getClass().getClassLoader());
		return ResponseEntity.ok(new HashMap<String, Object>(){{
			put("code", 0);
			put("msg", "ok");
			put("data", testApiService.data_v1());
		}});
	}
	
}

service


import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;

import com.spboot.config.cache.helper.CacheExpire;
import org.springframework.cache.annotation.CacheConfig;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;

//全局失效时间
@CacheExpire(ttl = 1, unit = TimeUnit.MINUTES)
@Service
public class TestApiService {

    //方法级别失效时间
	@CacheExpire(ttl = 10, unit = TimeUnit.SECONDS)
	@Cacheable
	public Map<String,String> data_v1() {
		Map<String,String> map = new HashMap<String, String>();
		map.put("k1", "v1");
		map.put("k2", "v2");
		map.put("k3", "v3");
		return map;
	}
	
}

启动类

import org.springframework.boot.SpringApplication;  
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication 
public class Application {
    public static void main(String[] args) {  
        SpringApplication.run(Application.class, args);
    }  
} 

测试接口

项目启动后调用http://localhost:8888/api/v10

进入redis-cli查看key以及对应的失效时间:

27.0.0.1:6379> keys *
1) "bart:spring:cache:com.spboot.api.TestApiService:data_v1:[]"

27.0.0.1:6379> ttl "bart:spring:cache:com.spboot.api.TestApiService:data_v1:[]"
(integer) 10 # 这里手速要快,因为失效时间只有10秒钟

如果redis中缓存key对应的失效时间确实是@CacheExpire配置的失效时间说明是好的。

原文地址:https://www.cnblogs.com/bartggg/p/15717748.html