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redis使用工具类进行保存数据和Ehcache注解缓存类实现缓存value

2018-03-21 15:30 856 查看

前言

本文主要是key value的形式。

这里我先说下序列化吧

GenericToStringSerializer:使用Spring转换服务进行序列化(可以用来专门转化存放Double等类型,我下面的工具类有介绍);

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;

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,那么Key只能是String类型的,不能为Long,Integer,否则会报错抛异常。

StringSerializer就是通过String.getBytes()来实现的,而且在Redis中,所有存储的值都是字符串类型的。所以这种方法保存后,通过Redis-cli控制台,是可以清楚的查看到我们保存了什么key,value是什么。它只能对String类型进行序列化

JdkSerializationRedisSerializer,这个序列化方法是Idk提供的,要求要被序列化的类继承自Serializeable接口,然后通过Jdk对象序列化的方法保存,这个序列化保存的对象,即使是个String类型的,在redis控制台,也是看不出来的,还是类似于 乱码的东西。因为它保存了一些对象的类型什么的额外信息。除非中间再加上一些objectmappr就可以看到内容了,如下

@Bean
public RedisTemplate<String, String> redisTemplate(RedisConnectionFactory factory) {
RedisTemplate<String, String> redisTemplate = new RedisTemplate<String, String>();
redisTemplate.setConnectionFactory(factory);

//key序列化方式,StringXX是转为String,JacksonXX是将对象转为json。
// 需要注意这里Key使用了StringRedisSerializer,那么Key只能是String类型的,不能为Long,Integer,否则会报错抛异常。
// 就是假如PostRepository里定义的@Cacheable(key="0")的话就会报错,因为这样作为key的是int型,key必须为String。
//所以在没有自己定义key生成策略的时候,可以不配置,我就没有配置
RedisSerializer<String> redisSerializer = new StringRedisSerializer();//Long类型不可以会出现异常信息;
redisTemplate.setKeySerializer(redisSerializer);

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);

redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);

return redisTemplate;
}




Ehcache和redis应该怎么用

我公司的项目中既有Ehcache 又有Redis,所以这里都会讲解

ehcache直接在jvm虚拟机中缓存,速度快,效率高;但是缓存共享麻烦,集群分布式应用不方便。

redis是通过socket访问到缓存服务,效率比ecache低,比数据库要快很多,处理集群和分布式缓存方便,有成熟的方案。

如果是单个应用或者对缓存访问要求很高的应用,用ehcache。

如果是大型系统,存在缓存共享、分布式部署、缓存内容很大的,建议用redis。

补充下:ehcache也有缓存共享方案,不过是通过RMI或者Jgroup多播方式进行广播缓存通知更新,缓存共享复杂,维护不方便;简单的共享可以,但是涉及到缓存恢复,大数据缓存,则不合适

1、springBoot引入spring配置文件,进行redis的搭建

@ImportResource(value = "classpath:applicationContext.xml")
@SpringBootApplication
public class SinoredisSpringbootApplication {

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


1.1、spring配置文件如下

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> 
<description>spring configuration</description>

<import resource="applicationContext-redis.xml"/>

</beans>


1.2、redis配置信息在properties中如下

########################################################
###REDIS (RedisProperties) red
4000
is
########################################################
hlj.redis.host-name=127.0.0.1
hlj.redis.password=
hlj.redis.max-total=64
hlj.redis.max-idle=30
hlj.redis.port=6379
hlj.redis.pool.max-wait=-1


1.3、redis配置文件如下

这里可以看到我使用了自定义的key 和value的序列化方式

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> 
<bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig" >
<property name="maxTotal" value="${hlj.redis.max-total}"/>
<property name="maxIdle" value="${hlj.redis.max-idle}"/>
<property name="maxWaitMillis" value="${hlj.redis.pool.max-wait}"/>
</bean>

<bean id="jedisFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" destroy-method="destroy">
<property name="password" value="${hlj.redis.password}"/>
<property name="hostName" value="${hlj.redis.host-name}"/>
<property name="port" value="${hlj.redis.port}"/>
<property name="usePool" value="true"/>
<property name="poolConfig" ref="jedisPoolConfig"/>
</bean>

<bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate" scope="prototype">
<property name="connectionFactory" ref="jedisFactory"/>
<property name="keySerializer">
<bean class="com.hlj.redis.cache.CustomStringRedisSerializer"/>
</property>
<property name="valueSerializer">
<bean class="com.hlj.redis.cache.CustomJSONStringRedisSerializer"/>
</property>
</bean>
</beans>


1.3.1 自定义key的序列化方式

package com.hlj.config.serializer;

import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.util.Assert;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.charset.Charset;

/**
* 类名称:CustomStringRedisSerializer
* 类描述:定制String 序列转换
* 创建人:qingxu
* 修改人:
* 修改时间:2016/3/2 15:04
* 修改备注:
*
* @version 1.0.0
*/
public class CustomStringRedisSerializer implements RedisSerializer<Object> {

private final Charset charset;

public CustomStringRedisSerializer() {
this(Charset.forName("UTF8"));
}

public CustomStringRedisSerializer(Charset charset) {
Assert.notNull(charset);
this.charset = charset;
}

public String deserialize(byte[] bytes) {
return bytes == null?null:new String(bytes, this.charset);
}

public byte[] serialize(Object string) {
if(string == null ) {
return null;
}
if(string instanceof Long){
return String.valueOf(string).getBytes(this.charset);

}
if(string instanceof Integer){
return String.valueOf(string).getBytes(this.charset);

}
if(string instanceof BigDecimal){
return ((BigDecimal)string).toString().getBytes(this.charset);
}

if(string instanceof BigInteger){
return ((BigInteger)string).toString().getBytes(this.charset);
}

if(string instanceof Double){
return ((Double)string).toString().getBytes(this.charset);
}

if(string instanceof Float){
return ((Float)string).toString().getBytes(this.charset);
}
return ((String)string).getBytes(this.charset);
}
}


1.3.2、自定义value的序列化方式

package com.hlj.config.serializer;

import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.SerializationException;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

/**
* 类名称:CustomJSONStringRedisSerializer
* 类描述:转换对象为json字符串
* 创建人:qingxu
* 修改人:
* 修改时间:2016/3/2 15:04
* 修改备注:
*
* @version 1.0.0
*/
public class CustomJSONStringRedisSerializer implements RedisSerializer<Object> {

public static final String EMPTY_JSON = "{}";

public static final byte[] EMPTY_ARRAY = new byte[0];

private final ObjectMapper mapper;

/**
* Creates {@link CustomJSONStringRedisSerializer} and configures {@link ObjectMapper} for default typing.
*/
public CustomJSONStringRedisSerializer() {
this((String) null);
}

/**
* Creates {@link CustomJSONStringRedisSerializer} and configures {@link ObjectMapper} for default typing using the
* given {@literal name}. In case of an {@literal empty} or {@literal null} String the default
* {@link JsonTypeInfo.Id#CLASS} will be used.
*
* @param classPropertyTypeName Name of the JSON property holding type information. Can be {@literal null}.
*/
public CustomJSONStringRedisSerializer(String classPropertyTypeName) {

this(new RedisObjectMapper());

if (StringUtils.hasText(classPropertyTypeName)) {
mapper.enableDefaultTypingAsProperty(ObjectMapper.DefaultTyping.NON_FINAL, classPropertyTypeName);
} else {
mapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
}
}

/**
* Setting a custom-configured {@link ObjectMapper} is one way to take further control of the JSON serialization
* process. For example, an extended {@link} can be configured that provides custom serializers for
* specific types.
*
* @param mapper must not be {@literal null}.
*/
public CustomJSONStringRedisSerializer(ObjectMapper mapper) {
Assert.notNull(mapper, "ObjectMapper must not be null!");

mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES,false);
this.mapper = mapper;
}

/*
* (non-Javadoc)
* @see org.springframework.data.redis.serializer.RedisSerializer#serialize(java.lang.Object)
*/
@Override
public byte[] serialize(Object source) throws SerializationException {
if (source == null) {
return EMPTY_ARRAY;
}

try {
return mapper.writeValueAsBytes(source);
} catch (JsonProcessingException e) {
throw new SerializationException("Could not write JSON: " + e.getMessage(), e);
}
}

/*
* (non-Javadoc)
* @see org.springframework.data.redis.serializer.RedisSerializer#deserialize(byte[])
*/
@Override
public Object deserialize(byte[] source) throws SerializationException {
return deserialize(source, Object.class);
}

/**
* @param source can be {@literal null}.
* @param type must not be {@literal null}.
* @return {@literal null} for empty source.
* @throws SerializationException
*/
public <T> T deserialize(byte[] source, Class<T> type) throws SerializationException {

Assert.notNull(type,
"Deserialization type must not be null! Pleaes provide Object.class to make use of Jackson2 default typing.");

if (source == null || source.length == 0) {
return null;
}

try {
return mapper.readValue(source, type);
} catch (Exception ex) {
throw new SerializationException("Could not read JSON: " + ex.getMessage(), ex);
}
}
}


1.3.4、如果使用上面序列化的话,那么redis库总可以看到是class或者是请他的java数据类型,下图是后期的答案,这里只是简单的介绍





1.4、至此,其实redis就已经搭建好了

2、、reids存储对象工具类

2.1、工具类

1、这个工具类,在描述的时候,就说道,分不清Long和Integer,Double和Float。所以我们一般只用来存放对象

2、本类中可以看到有两个服务类
ValueOperations
RedisOperations
,但是其实是同一个类只不过名字不同。只是其作用的范围表面上意思不一样,第一个是用来存取数据,第二个用来操作参数数据的

package com.hlj.redis.redisTool;

import org.springframework.data.redis.core.RedisOperations;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;

/**
* 类描述:
* 操作redis 对象数据的工具类
* 提供存取数字外对象的存取,数字类型使用RedisLongData/RedisIntegerData进行操作
* 这个类分不清Long和Integer,Float和Double。也无法进行原子操作
* 创建人: j.sh
* 创建时间: 2016/3/1
* version:1.0.0
*/
@Component
public class RedisObjectData {

@Resource(name="redisTemplate")
private ValueOperations<String, Object> valueOperations;

@Resource(name = "redisTemplate")
private RedisOperations<String,Object> operations;

/**
* 根据key获取数据
* @param key
* @return
*/
public Object getData(String key) {
return valueOperations.get(key);
}

/**
* 设置数据
* @param key
* @param object
*/
public void setData(String key,Object object) {
valueOperations.set(key,object);
}

/**
* 根据key 删除对应的数据
* @param key
*/
public void delete(String key) {
operations.delete(key);
}
}


2.2、controller测试

2.2.1、添加缓存对象和读取缓存对象

package com.hlj.controller;

import com.hlj.Format.ResponseBean;
import com.hlj.bean.Person;
import com.hlj.redis.redisTool.RedisLongData;
import com.hlj.redis.redisTool.RedisObjectData;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.ArrayList;
import java.util.List;

@Controller
public class RedisObjectDataController {

@Autowired
private RedisObjectData redisObjectData;

/**
* 添加缓存对象
*/
@RequestMapping("/setRedisObjectData")
public @ResponseBody ResponseBean setRedisObjectData(Long id){
try {
Person person = new Person();
person.setName("HealerJean");
person.setPwd("123456");
person.setId(id);
redisObjectData.setData("person", person);
return  ResponseBean.buildSuccess();
}catch (Exception e){
return ResponseBean.buildFailure(e.getMessage());
}
}

/**
* 根据key获取缓存对象
* @return
*/
@RequestMapping("/getRedisObjectData")
public @ResponseBody ResponseBean getRedisObjectData(String key){
try {
Person person = (Person) redisObjectData.getData(key);
return ResponseBean.buildSuccess(person);
}catch (Exception e){
return  ResponseBean.buildFailure(e.getMessage());
}
}


服务器启动:

1.1、浏览器打开输入 http://localhost:8080/setRedisObjectData?id=1



1.2、查看redis中的数据,发现已经有数据了数据了



2.1、对数据进行读取,浏览器中打开http://localhost:8080/getRedisObjectData?key=person



2.2、上述读取数据成功

2.2.2、 根据key值删除缓存

/**
* 根据key删除缓存对象
* @return
*/
@RequestMapping("/delRedisObjectData")
public @ResponseBody ResponseBean delRedisObjectData(String key){
try {
redisObjectData.delete(key);
return ResponseBean.buildSuccess();
}catch (Exception e){
return  ResponseBean.buildFailure(e.getMessage());
}
}


1.1、浏览器中打开 http://localhost:8080/delRedisObjectData?key=person



1.2、查看redis库,删除成功



2.2.3、存储List对象集合

/**
* 添加List缓存对象
* @param id
* @return
*/
@RequestMapping("/setListRedisObjectData")
public @ResponseBody ResponseBean setListRedisObjectData(Long id){
try {
List<Person> persons = new ArrayList<>();
Person person1= new Person(id,"HealerJean"+id,"password"+id);
Person person2 = new Person(id+1,"HuangLiang"+id,"HuangLiang"+id);
persons.add(person1);
persons.add(person2);
redisObjectData.setData("persons", persons);
return  ResponseBean.buildSuccess();
}catch (Exception e){
return ResponseBean.buildFailure(e.getMessage());
}
}

/**
* 根据key获取缓存List对象
* @return
*/
@RequestMapping("/getListRedisObjectData")
public @ResponseBody ResponseBean getListRedisObjectData(String key){
try {
List<Person> persons = (List<Person>) redisObjectData.getData(key);
return ResponseBean.buildSuccess(persons);
}catch (Exception e){
return  ResponseBean.buildFailure(e.getMessage());
}
}


1.1、浏览器中打开http://localhost:8080/setListRedisObjectData?id=1



1.2、查看redis库,有数据



2.1、根据key值获取list对象,浏览器中打开http://localhost:8080/getListRedisObjectData?key=persons



2.2、成功,下面要测试,清除下redis库

fulshdb


2.2.4、测试放入Long,报错误异常Integer不能转化为Long

/**
* 添加Long类型缓存对象,这是个错误的演示,仅供测试
* @param id
* @return
*/
@RequestMapping("/set")
public @ResponseBody ResponseBean set(Long id){
try {

redisObjectData.setData("id", id);
return  ResponseBean.buildSuccess();
}catch (Exception e){
return ResponseBean.buildFailure(e.getMessage());
}
}

/**
* 根据key获取Long,这是个错误的演示,仅供测试
* @return
*/
@RequestMapping("/get")
public @ResponseBody ResponseBean get(String key){
try {
Long id = (Long) redisObjectData.getData("id");
return ResponseBean.buildSuccess(id);
}catch (Exception e){
return  ResponseBean.buildFailure(e.getMessage());
}
}


1.1、浏览器中打开http://localhost:8080/set?id=1



1.2、查看redis库



2.1、根据key值获取,这个时候 就会报错了,朋友们,提示Integer不能转化为long



3、redis存取Long类型工具类

3.1、工具类代码

package com.hlj.redis.redisTool;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.data.redis.serializer.GenericToStringSerializer;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.concurrent.TimeUnit;

/**
* 类描述:
* redis操作Long类型数据的工具类
* 提供Long类型原子操作
* 默认一天过期,其他过期时间调用setExpire
* 创建人: j.sh
* 创建时间: 2016/3/1
* version:1.0.0
*/
@Component
public class RedisLongData implements InitializingBean {

@Resource(name="redisTemplate")
private ValueOperations<String, Long> valueOperations;

@Resource(name="redisTemplate")
private RedisTemplate<String,Long> redisTemplate;

@Override
public void afterPropertiesSet() throws Exception {
redisTemplate.setValueSerializer(new GenericToStringSerializer<Long>(Long.class));
valueOperations = redisTemplate.opsForValue();
}

/**
* 根据key 删除
* @param key
*/
public void delete(String key) {
redisTemplate.delete(key);
}

/**
* 进行数值的增加
* @param key
* @param value
* @return
*/
public Long increase(String key,long value){
Long result = valueOperations.increment(key,value);
this.setExpire(key,1L,TimeUnit.DAYS);
return result;
}

/**
* 进行数值的增加
* @param key
* @return
*/
public Long increase(String key){
return increase(key,1);
}

/**
* 进行数值的递减
* @param key
* @param value
* @return
*/
public Long decrease(String key,long value){
Long result =  valueOperations.increment(key,0-value);
this.setExpire(key,1L,TimeUnit.DAYS);
return result;
}

/**
* 进行数值的递减
* @param key
* @return
*/
public Long decrease(String key){
return decrease(key,1);
}

/**
* 根据key获取
* @param key
* @return
*/
public Long get(String key) {
return valueOperations.get(key);
}

/**
* 设置
* @param key
* @param value
*/
public void set(String key,Long value) {
valueOperations.set(key,value);
this.setExpire(key,1L,TimeUnit.DAYS);
}

/**
* 过期时间,默认单位秒
* @param key
* @param time
*/
public void setExpire(String key,Long time){
redisTemplate.expire(key,time, TimeUnit.SECONDS);
}

/**
* 过期时间
* @param key
* @param time
* @param timeUnit
*/
public void setExpire(String key,Long time,TimeUnit timeUnit){
redisTemplate.expire(key,time,timeUnit);
}

}


3.2、controller测试。没啥问题。自己测试吧

package com.hlj.controller;

import com.hlj.Format.ResponseBean;
import com.hlj.redis.redisTool.RedisLongData;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class RedisLongDataController {

@Autowired
private RedisLongData redisLongData;

/**
* 添加Long类型的缓存数据
*/
@RequestMapping("/setRedisLongData")
public @ResponseBody  ResponseBean setRedisLongData(Long id){
try {
redisLongData.set("long",id);
return  ResponseBean.buildSuccess();
}catch (Exception e){
return ResponseBean.buildFailure(e.getMessage());
}
}

/**
* 获取Long类型的缓存数据
*/

@RequestMapping("/getRedisLongData")
public @ResponseBody ResponseBean getRedisLongData(String key){
try {
Long id = redisLongData.get(key);
return ResponseBean.buildSuccess(id);
}catch (Exception e){
return  ResponseBean.buildFailure(e.getMessage());
}
}

}


4、Ehcache

那么关于它的使用,我先说明,这里是要使用注解的,而且是非常完美的注解

1、依赖的导入

<!--
包含支持UI模版(Velocity,FreeMarker,JasperReports),
邮件服务,
脚本服务(JRuby),
缓存Cache(EHCache),
任务计划Scheduling(uartz)。
-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
</dependency>
<!-- 集成ehcache需要的依赖-->
<dependency>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache</artifactId>
</dependency>


2、缓存配置文件

之前学习的时候,这个配置文件中药写入value的缓存策略,但是我做了一个自定义的缓存管理器,直接在Java类中配置常量就可以了,非常小巧和方便

<!--
~ Hibernate, Relational Persistence for Idiomatic Java
~
~ Copyright (c) 2007, Red Hat Middleware LLC or third-party contributors as
~ indicated by the @author tags or express copyright attribution
~ statements applied by the authors. All third-party contributions are
~ distributed under license by Red Hat Middleware LLC.
~
~ This copyrighted material is made available to anyone wishing to use, modify,
~ copy, or redistribute it subject to the terms and conditions of the GNU
~ Lesser General Public License, as published by the Free Software Foundation.
~
~ This program is distributed in the hope that it will be useful,
~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
~ or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
~ for more details.
~
~ You should have received a copy of the GNU Lesser General Public License
~ along with this distribution; if not, write to:
~ Free Software Foundation, Inc.
~ 51 Franklin Street, Fifth Floor
~ Boston, MA  02110-1301  USA
-->
<ehcache updateCheck="false">

<!-- Sets the path to the directory where cache .data files are created.

If the path is a Java System Property it is replaced by
its value in the running VM.

The following properties are translated:
user.home - User's home directory
user.dir - User's current working directory
java.io.tmpdir - Default temp file path -->
<!--<diskStore path="c:\dev\cache"/>-->

<!--
name:Cache的唯一标识
maxElementsInMemory:内存中最大缓存对象数
maxElementsOnDisk:磁盘中最大缓存对象数,若是0表示无穷大
eternal:Element是否永久有效,一但设置了,timeout将不起作用
overflowToDisk:配置此属性,当内存中Element数量达到maxElementsInMemory时,Ehcache将会Element写到磁盘中
timeToIdleSeconds:设置Element在失效前的允许闲置时间。仅当element不是永久有效时使用,可选属性,默认值是0,也就是可闲置时间无穷大
timeToLiveSeconds:设置Element在失效前允许存活时间。最大时间介于创建时间和失效时间之间。仅当element不是永久有效时使用,默认是0.,也就是element存活时间无穷大
diskPersistent:是否缓存虚拟机重启期数据
diskExpiryThreadIntervalSeconds:磁盘失效线程运行时间间隔,默认是120秒
diskSpoolBufferSizeMB:这个参数设置DiskStore(磁盘缓存)的缓存区大小。默认是30MB。每个Cache都应该有自己的一个缓冲区
memoryStoreEvictionPolicy:当达到maxElementsInMemory限制时,Ehcache将会根据指定的策略去清理内存。默认策略是LRU(最近最少使用)。你可以设置为FIFO(先进先出)或是LFU(较少使用)
-->

<defaultCache
maxElementsInMemory="10000"
eternal="false"
timeToIdleSeconds="600"
timeToLiveSeconds="600"
overflowToDisk="true"
maxElementsOnDisk="10000000"
diskPersistent="false"
diskExpiryThreadIntervalSeconds="120"
diskSpoolBufferSizeMB="64"
memoryStoreEvictionPolicy="LRU"
/>
<!--中间可以包含其他的缓存key-->

</ehcache>


3、spring中进行配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:cache="http://www.springframework.org/schema/cache"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd " >

<description>spring configuration</description>

<import resource="applicationContext-redis.xml"/>

<!-- 自定义Ehcache缓存,根据java类加入更多的key 支持注解缓存   -->
<cache:annotation-driven/>

<bean id="cacheManager" class="com.hlj.Ehcache.config.CustomEhCacheManager">
<property name="cacheManager" ref="ehcacheManager"/>
</bean>

<bean id="ehcacheManager" class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean">
<property name="configLocation" value="classpath:ehcache.xml"/>
<property name="shared" value="true"/>
</bean>

</beans>


3.1、配置自定义的缓存管理器

package com.hlj.Ehcache.config;

import net.sf.ehcache.Ehcache;
import net.sf.ehcache.config.CacheConfiguration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cache.Cache;
import org.springframework.cache.ehcache.EhCacheCache;
import org.springframework.cache.ehcache.EhCacheCacheManager;

import java.lang.reflect.Field;
import java.util.*;

/**
*  类描述:继承 EhCacheCacheManager
* @Description 初始化缓存。加载@CacheConstants中缓存定义及缓存自定义过期时间
* @Date   2018/3/21 下午2:46.
*/
public class CustomEhCacheManager extends EhCacheCacheManager {

private static String CACHE_PREFIX = "CACHE_";
private static String EXPIRE_PREFIX = "EXPIRE_";
private static Logger logger = LoggerFactory.getLogger(CustomEhCacheManager.class);

private static List<String> cacheNames = new ArrayList<>();
private static Map<String,Long> expires = new HashMap<>();

@Override
public void afterPropertiesSet() {
try {
Class clazz = CacheConstants.class;
Field[] fields = clazz.getDeclaredFields();
for(Field field : fields){
if (field.getName().startsWith(CACHE_PREFIX)){
cacheNames.add(field.get(clazz).toString());
} else if (field.getName().startsWith(EXPIRE_PREFIX)){
expires.put(
clazz.getField(field.getName().replace(EXPIRE_PREFIX,"")).get(clazz).toString(),
Long.parseLong(field.get(clazz).toString())
);
}
}
} catch (Exception e) {
logger.error(e.getMessage(),e);
throw new RuntimeException("init cache failure!",e);
}
super.afterPropertiesSet();
}

@Override
protected Collection<Cache> loadCaches() {
LinkedHashSet<Cache> caches = new LinkedHashSet<Cache>(cacheNames.size());
for(String name:cacheNames){
Ehcache exist = this.getCacheManager().addCacheIfAbsent(name);
if(exist != null){
Cache cache = new EhCacheCache(exist);
Ehcache ehcache = (Ehcache) cache.getNativeCache();
CacheConfiguration configuration = ehcache.getCacheConfiguration();
Long time = expires.get(name);
configuration.setTimeToIdleSeconds(time);
configuration.setTimeToLiveSeconds(time);
caches.add(cache);
}
}
return caches;
}
}


3.2、字段以缓存策略的名称,也叫缓存位置名称

package com.hlj.Ehcache.config;

/**
* 类名称:CacheConstants
* 类描述:缓存常量类
* 创建人:HealerJean
* 需要初始化的缓存定义名称需要以CACHE_为前缀。如:CACHE_XXX
* 如果需要增加自定义过期时间,则增加过期时间变量定义EXPIRE_为前缀的缓存过期时间.如:EXPIRE_CACHE_XXX
* 如不设置自定义过期时间即默认spring cache中设置过期时间
*
* @version 1.0.0
*/
public class CacheConstants {

//公共缓存,1分钟过期时间
public static final String CACHE_PUBLIC_PERSON = "cache.public.person";
public static final Long EXPIRE_CACHE_PUBLIC_PERSON = 60L;

public static final String CACHE_PUBLIC = "cache.public";
public static final Long EXPIRE_CACHE_PUBLIC = 60L;

public static final String CACHE_PUBLIC_TEN_MINUTE = "cache.public.ten.minute";
public static final Long EXPIRE_CACHE_PUBLIC_TEN_MINUTE = 10 * 60L;

}


4、开始测试吧,朋友们,这里不像多讲解了,主要还是看代码吧,注释也非常详细

1、controller

package com.hlj.Ehcache.controller;

import com.hlj.Ehcache.service.EhcacheService;
import com.hlj.bean.Person;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;

/**
* @Description
* @Author HealerJean
* @Date 2018/3/21  下午1:58.
*/
@Controller
public class EhCacheController {

@Autowired
private EhcacheService ehcacheService;

@GetMapping("save")
public @ResponseBody Person save(Long id) {
Person person = new Person(id,"EhcacheHealerJean","123465");
return ehcacheService.save(person);
}

@GetMapping("findById")
public @ResponseBody Person findById(Long id) {
return ehcacheService.findById(id);
}

@GetMapping("update")
public @ResponseBody Person update(Person person) {
return ehcacheService.update(person);
}

@GetMapping("delete")
public @ResponseBody String delete(Long id) {
ehcacheService.delete(id);
return "删除成功";
}

@GetMapping("listPerson")
public@ResponseBody  List<Person> listPerson() {
return ehcacheService.listPerson();
}
}


4.2、service

package com.hlj.Ehcache.service.impl;

import com.hlj.Ehcache.config.CacheConstants;
import com.hlj.Ehcache.service.EhcacheService;
import com.hlj.bean.Person;
import com.hlj.repository.PersonRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;

import java.util.List;

/**
* @Description
* @Author HealerJean
* @Date 2018/3/21  下午1:59.
*/
@Service
public class EhcacheServiceImpl implements EhcacheService{

@Autowired
private PersonRepository personRepository;

//这里的单引号不能少,否则会报错,被识别是一个对象;
public static final String CACHE_KEY = "'person'";

/**
* value属性表示使用哪个缓存策略,缓存策略在ehcache.xml,现在存放在下面的实体类中,在启动的时候自动加载了
* 也叫缓存存放位置名称,不能为空
*/
public static final String DEMO_CACHE_NAME = CacheConstants.CACHE_PUBLIC_PERSON;

/**
* 保存数据,防止是更新的操作,所以将之前缓存的删除,事实上,我也并没有很成功的实现它,后来明白啦,哈,原来是list集合缓存的时候,添加要删除的哦
* @param Person
*/

@CacheEvict(value=DEMO_CACHE_NAME,key=CACHE_KEY)
public Person save(Person Person){
return personRepository.save(Person);
}

/**
* 查询数据.
* @param id
* @return
*/
@Cacheable(value=DEMO_CACHE_NAME ,key="'Person_'+#id")
public Person findById(Long id){
return personRepository.findOne(id);
}

/**
* 修改数据.
* 在支持Spring Cache的环境下,与@Cacheable不同的是使用@CachePut标注的方法在执行前不会去检查缓存中是否存在之前执行过的结果,而是每次都会执行该方法,并将执行结果以键值对的形式存入指定的缓存中。
@CachePut也可以标注在类上和方法上。使用@CachePut时我们可以指定的属性跟@Cacheable是一样的。
*/
@CachePut(value = DEMO_CACHE_NAME,key = "'Person_'+#person.getId()")
public Person update(Person person)  {
Person Person = personRepository.findOne(person.getId());
Person.setName(person.getName());
Person.setPwd(person.getPwd());
return Person;
}

/**
* 删除数据.
* @param id
*/
@CacheEvict(value = DEMO_CACHE_NAME,key = "'Person_'+#id")//这是清除缓存.
public void delete(Long id){
personRepository.delete(id);
}

@Cacheable(value=DEMO_CACHE_NAME ,key=CACHE_KEY)
public List<Person> listPerson() {
return personRepository.findAll();
}
}


代码下载

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