Java轻量级缓存Ehcache与SpringBoot整合

前言

业务需要将数据临时存储一下，但是想做一个搭建轻量级应用，不需要任何第三方中间件（考虑过MySQL、Redis等都比较麻烦）。
Java EhCache是一个轻量级内存缓存，也支持持久化，所以采用该种方式。

配置

引入依赖

<dependencies>
    
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-testartifactId>
    dependency>
    
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-cacheartifactId>
    dependency>
    
    <dependency>
        <groupId>net.sf.ehcachegroupId>
        <artifactId>ehcacheartifactId>
    dependency>
    <dependency>
        <groupId>org.projectlombokgroupId>
        <artifactId>lombokartifactId>
    dependency>
dependencies>

启动类添加开启缓存注解

package com.terry;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;

/**
 * ehcache demo
 * @author terry
 * @version 1.0
 * @date 2022/4/18 11:38
 */
@SpringBootApplication
@EnableCaching
public class App {
    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}

ehcache.xml配置

<ehcache
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd"
        updateCheck="false">
    
    <diskStore path="base_ehcache"/>

    
    <defaultCache
            maxElementsInMemory="20000"
            eternal="true"
            timeToIdleSeconds="0"
            timeToLiveSeconds="0"
            overflowToDisk="true"
            maxElementsOnDisk="10000000"
            diskPersistent="true"
            diskExpiryThreadIntervalSeconds="0"
            memoryStoreEvictionPolicy="LRU"/>

ehcache>

application.yml 配置

spring:
  # 缓存配置
  cache:
    type: ehcache
    ehcache:
      config: classpath:ehcache.xml

实战 增删改查例子

package com.terry.ehcache.test;

import com.terry.App;
import lombok.extern.java.Log;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.Map;

/**
 * ehcache 增删改查测试
 * @author terry
 * @version 1.0
 * @date 2022/4/25 23:01
 */
@SpringBootTest(classes = App.class)
@Log
public class TestEhCache {

    @Autowired
    private CacheManager cacheManager;

    @Test
    public Cache getCache(){
        String cacheName = "user";
        Cache user = cacheManager.getCache(cacheName);
        if (user == null) {
            cacheManager.addCache(cacheName);
            user = cacheManager.getCache(cacheName);
        }
        return user;
    }

    @Test
    public void addUser(){
        Cache cache = getCache();
        // 添加一个用户，key:user01,value:张三
        cache.put(new Element("user01", "张三"));
    }

    @Test
    public void getUser(){
        Cache cache = getCache();
        log.info(cache.get("user01").getObjectValue().toString());
    }

    @Test
    public void removeUser(){
        Cache cache = getCache();
        cache.remove("user01");
        // 获取所有的keys
        log.info(cache.getKeys().toString());
    }

    @Test
    public void getUserAll(){
        Cache cache = getCache();
        cache.put(new Element("user01", "张三"));
        cache.put(new Element("user02", "李四"));
        cache.put(new Element("user03", "王五"));
        cache.put(new Element("user04", "赵六"));
        // 获取所有的keys
        Map<Object, Element> all = cache.getAll(cache.getKeys());
        all.forEach((k, v) -> {
            log.info("key:" + k + ", value:" + v.getObjectValue().toString());
        });
    }
}

使用SpringBoot Cache注解

package com.terry.ehcache.service;

import lombok.Data;
import lombok.extern.java.Log;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

/**
 * 用户服务层
 * @author terry
 * @version 1.0
 * @date 2022/4/18 14:35
 */
@Service
@Log
public class UserService {

    @Cacheable(cacheNames = "user")
    public List<User> getUser(){
        log.info("添加进缓存");
        // 模拟数据库
        List<User> list = new ArrayList<>();
        list.add(new User("张三", 18));
        list.add(new User("李四", 18));
        return list;
    }

    @Data
    public static class User implements Serializable {
        private String name;
        private int age;
        public User(String name, int age) {
            this.name = name;
            this.age = age;
        }
    }
}

封装工具类

import lombok.extern.slf4j.Slf4j;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.Map;

/**
 * ehcache 工具类
 * @version 1.0
 * @author terry
 * @date 2022/4/22
 */
@Slf4j
@Component
public class EhcacheService {
 

    @Autowired
    private CacheManager cacheManager;

    /**
     * 获得一个Cache，没有则创建一个。
     * @return
     */
    private Cache getCache(){
        return getCache(EhcacheEnum.CACHE_NAME);
    }

    /**
     * 获得一个Cache，没有则创建一个。
     * @param cacheName
     * @return
     */
    public Cache getCache(String cacheName){
        Cache cache = cacheManager.getCache(cacheName);
        if (cache == null){
            cacheManager.addCache(cacheName);
            cache = cacheManager.getCache(cacheName);
            cache.getCacheConfiguration().setEternal(true);
        }
        return cache;
    }

    /**
     * 放置缓存(带过期时间)
     * @param key
     * @param value
     * @param timeToLiveSeconds
     */
    public void setCacheElement(String key, Object value,int timeToLiveSeconds) {
        Element element = new Element(key, value);
        element.setEternal(false);
        element.setTimeToLive(timeToLiveSeconds);
        getCache().put(element);
    }

    /**
     * 放置缓存(带过期时间)
     * @param cacheName
     * @param key
     * @param value
     * @param timeToLiveSeconds
     */
    public void setCacheElement(String cacheName, String key, Object value,int timeToLiveSeconds) {
        Element element = new Element(key, value);
        element.setEternal(false);
        element.setTimeToLive(timeToLiveSeconds);
        getCache(cacheName).put(element);
    }

    /**
     * 放置缓存(永久)
     * @param key
     * @param value
     */
    public void setCacheElement(String key, Object value) {
        Element element = new Element(key, value);
        element.setEternal(false);
        getCache().put(element);
    }

    /**
     * 放置缓存(永久)
     * @param cacheName
     * @param key
     * @param value
     */
    public void setCacheElement(String cacheName, String key, Object value) {
        Element element = new Element(key, value);
        element.setEternal(false);
        getCache(cacheName).put(element);
    }

    /**
     * 设置过期时间
     * @param key
     * @param seconds
     * @return
     */
    public long expire(String key,int seconds) {
        Element element = getCache().get(key);
        element.setEternal(false);
        element.setTimeToLive(seconds);
        return 0;
    }

    /**
     * 设置过期时间
     * @param key
     * @param cacheName
     * @param seconds
     * @return
     */
    public long expire(String key,String cacheName, int seconds) {
        Element element = getCache(cacheName).get(key);
        element.setEternal(false);
        element.setTimeToLive(seconds);
        return 0;
    }

    /**
     * 获取缓存值
     * @param key
     * @return
     */
    public Object getCacheValue(String key) {
        Element element = getCache().get(key);
        if(element != null)
        {
            return element.getObjectValue();
        }
        return null;
    }

    /**
     * 获取缓存值
     * @param cacheName
     * @param key
     * @return
     */
    public Object getCacheValue(String cacheName, String key) {
        Element element = getCache(cacheName).get(key);
        if(element != null)
        {
            return element.getObjectValue();
        }
        return null;
    }

    /**
     * 根据key删除缓存
     * @param cacheName
     * @return
     */
    public Map<Object, Element> getCacheAll(String cacheName) {
        Cache cache = getCache(cacheName);
        return cache.getAll(cache.getKeys());
    }

    /**
     * 根据key删除缓存
     * @param cacheName
     * @param key
     * @return
     */
    public Boolean removeCacheKey(String cacheName, String key) {
        return getCache(cacheName).remove(key);
    }
    /**
     * 获取缓存过期时间
     * @param key
     * @return
     */
    public int getCacheExpire(String key) {
        Element element = getCache().get(key);
        List keys = getCache().getKeys();
        if(element != null)
        {
            return element.getTimeToLive();
        }
        return 0;
    }
    /**
     * 获取缓存过期时间
     * @param cacheName
     * @param key
     * @return
     */
    public int getCacheExpire(String cacheName, String key) {
        Element element = getCache(cacheName).get(key);
        if(element != null)
        {
            return element.getTimeToLive();
        }
        return 0;
    }
 
}