使用ehcache三步搞定springboot緩存的方法示例
本次內(nèi)容主要介紹基于Ehcache 3.0來快速實現(xiàn)Spring Boot應用程序的數(shù)據(jù)緩存功能。在Spring Boot應用程序中,我們可以通過Spring Caching來快速搞定數(shù)據(jù)緩存。接下來我們將介紹如何在三步之內(nèi)搞定Spring Boot緩存。
1. 創(chuàng)建一個Spring Boot工程并添加Maven依賴
你所創(chuàng)建的Spring Boot應用程序的maven依賴文件至少應該是下面的樣子:
<?xml version="1.0" encoding="UTF-8"?> <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> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.ramostear</groupId> <artifactId>cache</artifactId> <version>0.0.1-SNAPSHOT</version> <name>cache</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-cache</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.ehcache</groupId> <artifactId>ehcache</artifactId> </dependency> <dependency> <groupId>javax.cache</groupId> <artifactId>cache-api</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
依賴說明:
- spring-boot-starter-cache為Spring Boot應用程序提供緩存支持
- ehcache提供了Ehcache的緩存實現(xiàn)
- cache-api 提供了基于JSR-107的緩存規(guī)范
2. 配置Ehcache緩存
現(xiàn)在,需要告訴Spring Boot去哪里找緩存配置文件,這需要在Spring Boot配置文件中進行設置:
spring.cache.jcache.config=classpath:ehcache.xml
然后使用@EnableCaching注解開啟Spring Boot應用程序緩存功能,你可以在應用主類中進行操作:
package com.ramostear.cache;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;
@SpringBootApplication
@EnableCaching
public class CacheApplication {
public static void main(String[] args) {
SpringApplication.run(CacheApplication.class, args);
}
}
接下來,需要創(chuàng)建一個ehcache的配置文件,該文件放置在類路徑下,如resources目錄下:
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.ehcache.org/v3"
xmlns:jsr107="http://www.ehcache.org/v3/jsr107"
xsi:schemaLocation="
http://www.ehcache.org/v3 http://www.ehcache.org/schema/ehcache-core-3.0.xsd
http://www.ehcache.org/v3/jsr107 http://www.ehcache.org/schema/ehcache-107-ext-3.0.xsd">
<service>
<jsr107:defaults enable-statistics="true"/>
</service>
<cache alias="person">
<key-type>java.lang.Long</key-type>
<value-type>com.ramostear.cache.entity.Person</value-type>
<expiry>
<ttl unit="minutes">1</ttl>
</expiry>
<listeners>
<listener>
<class>com.ramostear.cache.config.PersonCacheEventLogger</class>
<event-firing-mode>ASYNCHRONOUS</event-firing-mode>
<event-ordering-mode>UNORDERED</event-ordering-mode>
<events-to-fire-on>CREATED</events-to-fire-on>
<events-to-fire-on>UPDATED</events-to-fire-on>
<events-to-fire-on>EXPIRED</events-to-fire-on>
<events-to-fire-on>REMOVED</events-to-fire-on>
<events-to-fire-on>EVICTED</events-to-fire-on>
</listener>
</listeners>
<resources>
<heap unit="entries">2000</heap>
<offheap unit="MB">100</offheap>
</resources>
</cache>
</config>
最后,還需要定義個緩存事件監(jiān)聽器,用于記錄系統(tǒng)操作緩存數(shù)據(jù)的情況,最快的方法是實現(xiàn)CacheEventListener接口:
package com.ramostear.cache.config;
import org.ehcache.event.CacheEvent;
import org.ehcache.event.CacheEventListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* @author ramostear
* @create-time 2019/4/7 0007-0:48
* @modify by :
* @since:
*/
public class PersonCacheEventLogger implements CacheEventListener<Object,Object>{
private static final Logger logger = LoggerFactory.getLogger(PersonCacheEventLogger.class);
@Override
public void onEvent(CacheEvent cacheEvent) {
logger.info("person caching event {} {} {} {}",
cacheEvent.getType(),
cacheEvent.getKey(),
cacheEvent.getOldValue(),
cacheEvent.getNewValue());
}
}
3. 使用@Cacheable注解對方法進行注釋
要讓Spring Boot能夠緩存我們的數(shù)據(jù),還需要使用@Cacheable注解對業(yè)務方法進行注釋,告訴Spring Boot該方法中產(chǎn)生的數(shù)據(jù)需要加入到緩存中:
package com.ramostear.cache.service;
import com.ramostear.cache.entity.Person;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;
/**
* @author ramostear
* @create-time 2019/4/7 0007-0:51
* @modify by :
* @since:
*/
@Service(value = "personService")
public class PersonService {
@Cacheable(cacheNames = "person",key = "#id")
public Person getPerson(Long id){
Person person = new Person(id,"ramostear","ramostear@163.com");
return person;
}
}
通過以上三個步驟,我們就完成了Spring Boot的緩存功能。接下來,我們將測試一下緩存的實際情況。
4. 緩存測試
為了測試我們的應用程序,創(chuàng)建一個簡單的Restful端點,它將調(diào)用PersonService返回一個Person對象:
package com.ramostear.cache.controller;
import com.ramostear.cache.entity.Person;
import com.ramostear.cache.service.PersonService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @author ramostear
* @create-time 2019/4/7 0007-0:54
* @modify by :
* @since:
*/
@RestController
@RequestMapping("/persons")
public class PersonController {
@Autowired
private PersonService personService;
@GetMapping("/{id}")
public ResponseEntity<Person> person(@PathVariable(value = "id") Long id){
return new ResponseEntity<>(personService.getPerson(id), HttpStatus.OK);
}
}
Person是一個簡單的POJO類:
package com.ramostear.cache.entity;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;
import java.io.Serializable;
/**
* @author ramostear
* @create-time 2019/4/7 0007-0:45
* @modify by :
* @since:
*/
@Getter
@Setter
@AllArgsConstructor
@NoArgsConstructor
public class Person implements Serializable{
private Long id;
private String username;
private String email;
}
以上準備工作都完成后,讓我們編譯并運行應用程序。項目成功啟動后,使用瀏覽器打開: http://localhost:8080/persons/1 ,你將在瀏覽器頁面中看到如下的信息:
{"id":1,"username":"ramostear","email":"ramostear@163.com"}
此時在觀察控制臺輸出的日志信息:
2019-04-07 01:08:01.001 INFO 6704 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : Completed initialization in 5 ms
2019-04-07 01:08:01.054 INFO 6704 --- [e [_default_]-0] c.r.cache.config.PersonCacheEventLogger : person caching event CREATED 1 null com.ramostear.cache.entity.Person@ba8a729
由于我們是第一次請求API,沒有任何緩存數(shù)據(jù)。因此,Ehcache創(chuàng)建了一條緩存數(shù)據(jù),可以通過 CREATED 看一了解到。
我們在ehcache.xml文件中將緩存過期時間設置成了1分鐘(1),因此在一分鐘之內(nèi)我們刷新瀏覽器,不會看到有新的日志輸出,一分鐘之后,緩存過期,我們再次刷新瀏覽器,將看到如下的日志輸出:
2019-04-07 01:09:28.612 INFO 6704 --- [e [_default_]-1] c.r.cache.config.PersonCacheEventLogger : person caching event EXPIRED 1 com.ramostear.cache.entity.Person@a9f3c57 null
2019-04-07 01:09:28.612 INFO 6704 --- [e [_default_]-1] c.r.cache.config.PersonCacheEventLogger : person caching event CREATED 1 null com.ramostear.cache.entity.Person@416900ce
第一條日志提示緩存已經(jīng)過期,第二條日志提示Ehcache重新創(chuàng)建了一條緩存數(shù)據(jù)。
結(jié)束語
在本次案例中,通過簡單的三個步驟,講解了基于Ehcache的Spring Boot應用程序緩存實現(xiàn)。文章內(nèi)容重在緩存實現(xiàn)的基本步驟與方法,簡化了具體的業(yè)務代碼,有興趣的朋友可以自行擴展,期間遇到問題也可以隨時與我聯(lián)系。
以上就是本文的全部內(nèi)容,希望對大家的學習有所幫助,也希望大家多多支持腳本之家。
相關文章
Java 動態(tài)模擬操作系統(tǒng)進程調(diào)度算法
這篇文章主要介紹了采用java語言編程模擬N個進程采用動態(tài)高優(yōu)先權優(yōu)先進程調(diào)度算法。文中代碼具有一定的學習價值,感興趣的小伙伴可以了解一下2021-12-12
Java編程一維數(shù)組轉(zhuǎn)換成二維數(shù)組實例代碼
這篇文章主要介紹了Java編程一維數(shù)組轉(zhuǎn)換成二維數(shù)組,分享了相關代碼示例,小編覺得還是挺不錯的,具有一定借鑒價值,需要的朋友可以參考下2018-01-01

