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写后感:博主写这么一系列文章也不容易啊,请评论支持下。
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?????? 如果看过我之前(35)的文章这一篇的文章就会很简单,没有什么挑战性了。
?????? 那么我们先说说这一篇文章我们都会学到的技术点:Spring Data JPA,Spring Boot 使用Mysql,Spring MVC,EHCache,Spring Cache等(其中@Cacheable请看上一节的理论知识),具体分如下几个步骤:
(1)新建Maven Java Project
(2)在pom.xml中加入依赖包
(3)编写Spring Boot启动类;
(4)配置application.properties;
(5)编写缓存配置类以及ehcache.xml配置文件;
(6)编写DemoInfo实体类进行测试;
(7)编写持久类DemoInfoRepository;
(8)编写处理类DemoInfoService;
(9)编写DemoInfoController测试类;
(10)运行测试;
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以上就是具体的步骤了,那么接下来我们一起按照这个步骤来进行实现吧。
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(1)新建Maven Java Project
?????? 新建一个工程名为spring-boot-ehcache的maven java project。
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(2)在pom.xml中加入依赖包
?????? 在pom.xml文件中加入相应的依赖包,Spring Boot父节点依赖包;spring boot web支持;缓存依赖spring-context-support;集成ehcache需要的依赖;JPA操作数据库;mysql 数据库驱动,具体pom.xml文件:
<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>
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??? <groupId>com.kfit</groupId>
??? <artifactId>spring-boot-ehcache</artifactId>
??? <version>0.0.1-SNAPSHOT</version>
??? <packaging>jar</packaging>
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??? <name>spring-boot-ehcache</name>
??? <url>http://maven.apache.org</url>
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??? <properties>
?????? <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
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?????? <!-- 配置JDK编译版本. -->
?????? <java.version>1.8</java.version>
??? </properties>
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??? <!-- spring boot 父节点依赖,
?????? 引入这个之后相关的引入就不需要添加version配置,
?????? ?spring boot会自动选择最合适的版本进行添加。
??? -->
??? <parent>
?????? <groupId>org.springframework.boot</groupId>
?????? <artifactId>spring-boot-starter-parent</artifactId>
?????? <version>1.3.3.RELEASE</version>
??? </parent>
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??? <dependencies>
?????? <!-- 单元测试. -->
?????? <dependency>
?????????? <groupId>junit</groupId>
?????????? <artifactId>junit</artifactId>
?????????? <scope>test</scope>
?????? </dependency>
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?????? <!-- spring boot web支持:mvc,aop... -->
?????? <dependency>
?????????? <groupId>org.springframework.boot</groupId>
?????????? <artifactId>spring-boot-starter-web</artifactId>
?????? </dependency>
??????
?????? <!--
?????????? 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>
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?????? <!-- 集成ehcache需要的依赖-->
?????? <dependency>
?????????? <groupId>net.sf.ehcache</groupId>
?????????? <artifactId>ehcache</artifactId>
?????? </dependency>
??????
?????? <!-- JPA操作数据库. -->
?????? <dependency>
??? ????? <groupId>org.springframework.boot</groupId>
??? ????? <artifactId>spring-boot-starter-data-jpa</artifactId>
??? ??? </dependency>
??????
?????? <!-- mysql 数据库驱动. -->
?????? <dependency>
??? ????? <groupId>mysql</groupId>
??? ????? <artifactId>mysql-connector-java</artifactId>
??? ??? </dependency>
??? ???
??? ??? <!-- Spring boot单元测试. -->
?????? <dependency>
??????????? <groupId>org.springframework.boot</groupId>
??????????? <artifactId>spring-boot-starter-test</artifactId>
??????????? <scope>test</scope>
??????? </dependency>
??? </dependencies>
</project>
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(3)编写Spring Boot启动类(com.kfit.App.java);
package com.kfit;
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import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
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/**
?*
?*
?* @SpringBootApplication申明让spring boot自动给程序进行必要的配置,
?*
@SpringBootApplication
等待于:
@Configuration
@EnableAutoConfiguration
@ComponentScan
?*
?* @author Angel(QQ:412887952)
?* @version v.0.1
?*/
@SpringBootApplication
publicclass App {
??? publicstaticvoid main(String[] args) {
?????? SpringApplication.run(App.class, args);
??? }
}
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(4)配置application.properties;
?????? 在application.properties中主要配置数据库连接和JPA的基本配置,具体如下:
Src/main/resouces/application.properties:
########################################################
###datasource ,mysql数据库连接配置
########################################################
spring.datasource.url = jdbc:mysql://localhost:3306/test
spring.datasource.username = root
spring.datasource.password = root
spring.datasource.driverClassName = com.mysql.jdbc.Driver
spring.datasource.max-active=20
spring.datasource.max-idle=8
spring.datasource.min-idle=8
spring.datasource.initial-size=10
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########################################################
### Java Persistence Api ,JPA自动建表操作配置
########################################################
# Specify the DBMS
spring.jpa.database = MYSQL
# Show or not log for each sql query
spring.jpa.show-sql = true
# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = update
# Naming strategy
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
# stripped before adding them to the entity manager)
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
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(5)编写缓存配置类以及ehcache.xml配置文件:
?????? 这个类主要是注册缓存管理对象EhCacheCacheManager、缓存工厂对象EhCacheManagerFactoryBean,具体代码如下:
EhCacheManagerFactoryBean:
package com.kfit.config;
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import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.ehcache.EhCacheCacheManager;
import org.springframework.cache.ehcache.EhCacheManagerFactoryBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.ClassPathResource;
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/**
?* 缓存配置.
?* @author Angel(QQ:412887952)
?* @version v.0.1
?*/
@Configuration
@EnableCaching//标注启动缓存.
publicclass CacheConfiguration {
???
??? /**
??? ?*? ehcache 主要的管理器
??? ?* @param bean
??? ?* @return
??? ?*/
??? @Bean
??? public EhCacheCacheManager ehCacheCacheManager(EhCacheManagerFactoryBean bean){
?????? System.out.println("CacheConfiguration.ehCacheCacheManager()");
?????? returnnew EhCacheCacheManager(bean.getObject());
??? }
???
??? /*
??? ?? * 据shared与否的设置,
??? ?? * Spring分别通过CacheManager.create()
??? ?? * 或new CacheManager()方式来创建一个ehcache基地.
??? ?? *
??? ?? * 也说是说通过这个来设置cache的基地是这里的Spring独用,还是跟别的(如hibernate的Ehcache共享)
??? ?? *
??? ?? */
??? ? @Bean
??? ? public EhCacheManagerFactoryBean ehCacheManagerFactoryBean(){
??? ??? System.out.println("CacheConfiguration.ehCacheManagerFactoryBean()");
?????? EhCacheManagerFactoryBean cacheManagerFactoryBean = new EhCacheManagerFactoryBean ();
??? ??? cacheManagerFactoryBean.setConfigLocation (new ClassPathResource("conf/ehcache.xml"));
??? ??? cacheManagerFactoryBean.setShared(true);
??? ??? returncacheManagerFactoryBean;
??? ? }
???
}
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在src/main/resouces/conf下编写ehcache.xml配置文件,当然这个文件你可以放在其它目录下:
<?xml version="1.0" encoding="UTF-8"?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
??? xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd"
??? updateCheck="false">
???
???
??? <!--
??? diskStore:为缓存路径,ehcache分为内存和磁盘两级,此属性定义磁盘的缓存位置。参数解释如下:
?????? user.home – 用户主目录
?????? user.dir? – 用户当前工作目录
?????? java.io.tmpdir – 默认临时文件路径
??????
??? ?-->
??? <diskStore path="java.io.tmpdir/Tmp_EhCache" />
???
??? <!--
?????? defaultCache:默认缓存策略,当ehcache找不到定义的缓存时,则使用这个缓存策略。只能定义一个。
??? ?-->
??? ?
??? ?<!--
?????? name:缓存名称。
?????? maxElementsInMemory:缓存最大数目
?????? maxElementsOnDisk:硬盘最大缓存个数。?
?????? eternal:对象是否永久有效,一但设置了,timeout将不起作用。?
?????? overflowToDisk:是否保存到磁盘,当系统当机时
?????? timeToIdleSeconds:设置对象在失效前的允许闲置时间(单位:秒)。仅当eternal=false对象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:设置对象在失效前允许存活时间(单位:秒)。最大时间介于创建时间和失效时间之间。仅当eternal=false对象不是永久有效时使用,默认是0.,也就是对象存活时间无穷大。
?????? diskPersistent:是否缓存虚拟机重启期数据 Whether the disk store persists between restarts of the Virtual Machine. The default value is false.?
?????? 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。?
?????? diskExpiryThreadIntervalSeconds:磁盘失效线程运行时间间隔,默认是120秒。
?????? 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)。?
??????? clearOnFlush:内存数量最大时是否清除。
???????? memoryStoreEvictionPolicy:可选策略有:LRU(最近最少使用,默认策略)、FIFO(先进先出)、LFU(最少访问次数)。
???????? ?? FIFO,first in first out,这个是大家最熟的,先进先出。
???????? ?? LFU, Less Frequently Used,就是上面例子中使用的策略,直白一点就是讲一直以来最少被使用的。如上面所讲,缓存的元素有一个hit属性,hit值最小的将会被清出缓存。
???????? ?? LRU,Least Recently Used,最近最少使用的,缓存的元素有一个时间戳,当缓存容量满了,而又需要腾出地方来缓存新的元素的时候,那么现有缓存元素中时间戳离当前时间最远的元素将被清出缓存。
??? -->
??? <defaultCache
?????? eternal="false"
?????? maxElementsInMemory="1000"
?????? overflowToDisk="false"
?????? diskPersistent="false"
?????? timeToIdleSeconds="0"
?????? timeToLiveSeconds="600"
?????? memoryStoreEvictionPolicy="LRU" />
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??? <cache
?????? name="demo"??
?????? eternal="false"
?????? maxElementsInMemory="100"
?????? overflowToDisk="false"
?????? diskPersistent="false"
?????? timeToIdleSeconds="0"
?????? timeToLiveSeconds="300"
?????? memoryStoreEvictionPolicy="LRU" />
??????
</ehcache>
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(6)编写DemoInfo实体类进行测试;
在com.kfit.bean下编写DemoInfo实体类进行缓存测试:
package com.kfit.bean;
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import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
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/**
?* 测试实体类.
?* @author Angel(QQ:412887952)
?* @version v.0.1
?*/
@Entity
publicclass DemoInfo {
??? @Id@GeneratedValue
??? privatelongid;//主键.
??? private String name;//名称;
??? private String pwd;//密码;
??? privateintstate;
??? publiclong getId() {
?????? returnid;
??? }
??? publicvoid setId(longid) {
?????? this.id = id;
??? }
??? public String getName() {
?????? returnname;
??? }
??? publicvoid setName(String name) {
?????? this.name = name;
??? }
??? public String getPwd() {
?????? returnpwd;
??? }
??? publicvoid setPwd(String pwd) {
?????? this.pwd = pwd;
??? }
??? publicint getState() {
?????? returnstate;
??? }
??? publicvoid setState(intstate) {
?????? this.state = state;
??? }
??? @Override
??? public String toString() {
?????? return"DemoInfo [id=" + id + ", name=" + name + ", pwd=" + pwd + ", state=" + state + "]";
??? }
}
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(7)编写持久类DemoInfoRepository;
?????? 编写持久类DemoInfoRepository:
com.kfit.repository.DemoInfoRepository:
package com.kfit.repository;
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import org.springframework.data.repository.CrudRepository;
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import com.kfit.bean.DemoInfo;
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/**
?* 操作数据库.
?* @author Angel(QQ:412887952)
?* @version v.0.1
?*/
publicinterface DemoInfoRepository extends CrudRepository<DemoInfo,Long>{
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}
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(8)编写处理类DemoInfoService;
?????? 编写增删改查的方法,在这几个方法中都使用注解缓存,进行缓存的创建以及删除,修改等操作:
?com.kfit.service.DemoInfoService:
package com.kfit.service;
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import com.kfit.bean.DemoInfo;
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import javassist.NotFoundException;
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publicinterface DemoInfoService {
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??? void delete(Long id);
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??? DemoInfo update(DemoInfo updated) throws NotFoundException;
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??? DemoInfo findById(Long id);
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??? DemoInfo save(DemoInfo demoInfo);
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}
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com.kfit.service.impl.DemoInfoServiceImpl:
package com.kfit.service.impl;
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import javax.annotation.Resource;
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import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;
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import com.kfit.bean.DemoInfo;
import com.kfit.repository.DemoInfoRepository;
import com.kfit.service.DemoInfoService;
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import javassist.NotFoundException;
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@Service
publicclass DemoInfoServiceImpl implements DemoInfoService {
???
??? //这里的单引号不能少,否则会报错,被识别是一个对象;
??? publicstaticfinal String CACHE_KEY = "‘demoInfo‘";
??
??? ?@Resource
??? ?private DemoInfoRepository demoInfoRepository;
???
??? /**
??? ?* value属性表示使用哪个缓存策略,缓存策略在ehcache.xml
??? */
??? publicstaticfinal String DEMO_CACHE_NAME = "demo";
???
??? /**
??? ?* 保存数据.
??? ?* @param demoInfo
??? ?*/
??? @CacheEvict(value=DEMO_CACHE_NAME,key=CACHE_KEY)
??? @Override
??? public DemoInfo save(DemoInfo demoInfo){
?????? returndemoInfoRepository.save(demoInfo);
??? }
???
??? /**
??? ?* 查询数据.
??? ?* @param id
??? ?* @return
??? ?*/
??? @Cacheable(value=DEMO_CACHE_NAME,key="‘demoInfo_‘+#id")
??? @Override
??? public DemoInfo findById(Long id){
?????? System.err.println("没有走缓存!"+id);
?????? returndemoInfoRepository.findOne(id);
??? }
???
??? /**
??? ?* http://www.mincoder.com/article/2096.shtml:
??? ?*
??? ?* 修改数据.
??? ?*
??? ?* 在支持Spring Cache的环境下,对于使用@Cacheable标注的方法,Spring在每次执行前都会检查Cache中是否存在相同key的缓存元素,如果存在就不再执行该方法,而是直接从缓存中获取结果进行返回,否则才会执行并将返回结果存入指定的缓存中。@CachePut也可以声明一个方法支持缓存功能。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。
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?????? @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。
??? ?*
??? ?* @param updated
??? ?* @return
??? ?*
??? ?* @throws NotFoundException
??? ?*/
??? @CachePut(value = DEMO_CACHE_NAME,key = "‘demoInfo_‘+#updated.getId()")
??? //@CacheEvict(value = DEMO_CACHE_NAME,key = "‘demoInfo_‘+#updated.getId()")//这是清除缓存.
??? @Override
??? public DemoInfo update(DemoInfo updated) throws NotFoundException{
?????? DemoInfo demoInfo = demoInfoRepository.findOne(updated.getId());
?????? if(demoInfo == null){
?????????? thrownew NotFoundException("No find");
?????? }
?????? demoInfo.setName(updated.getName());
?????? demoInfo.setPwd(updated.getPwd());
?????? returndemoInfo;
??? }
???
???
??? /**
??? ?* 删除数据.
??? ?* @param id
??? ?*/
??? @CacheEvict(value = DEMO_CACHE_NAME,key = "‘demoInfo_‘+#id")//这是清除缓存.
??? @Override
??? publicvoid delete(Long id){
?????? demoInfoRepository.delete(id);
??? }
??? ??
???
}
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(9)编写DemoInfoController测试类;
编写一个rest进行测试:
com.kfit.controller.DemoInfoController:
package com.kfit.controller;
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import javax.annotation.Resource;
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import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
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import com.kfit.bean.DemoInfo;
import com.kfit.service.DemoInfoService;
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import javassist.NotFoundException;
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@RestController
publicclass DemoInfoController {
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??? @Resource
??? private DemoInfoService demoInfoService;
???
??? @RequestMapping("/test")
??? public String test(){
??????
?????? //存入两条数据.
??? ??? DemoInfo demoInfo = new DemoInfo();
??? ??? demoInfo.setName("张三");
??? ??? demoInfo.setPwd("123456");
??? ??? DemoInfo demoInfo2 = demoInfoService.save(demoInfo);
??????
??? ??? //不走缓存.
??? ??? System.out.println(demoInfoService.findById(demoInfo2.getId()));
??? ??? //走缓存.
??? ??? System.out.println(demoInfoService.findById(demoInfo2.getId()));
??? ???
??? ???
??? ??? demoInfo = new DemoInfo();
??? ??? demoInfo.setName("李四");
??? ??? demoInfo.setPwd("123456");
??? ??? DemoInfo demoInfo3 = demoInfoService.save(demoInfo);
??? ???
??? ??? //不走缓存.
??? ??? System.out.println(demoInfoService.findById(demoInfo3.getId()));
??? ??? //走缓存.
??? ??? System.out.println(demoInfoService.findById(demoInfo3.getId()));
??? ???
??? ??? System.out.println("============修改数据=====================");
??? ??? //修改数据.
??? ??? DemoInfo updated = new DemoInfo();
??? ??? updated.setName("李四-updated");
??? ??? updated.setPwd("123456");
??? ??? updated.setId(demoInfo3.getId());
??? ??? try {
?????????? System.out.println(demoInfoService.update(updated));
?????? } catch (NotFoundException e) {
?????????? e.printStackTrace();
?????? }
??? ???
??? ??? //不走缓存.
??? ??? System.out.println(demoInfoService.findById(updated.getId()));
??? ???
?????? return"ok";
??? }
???
???
}
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(10)运行测试;
运行App.java进行测试,访问:http://127.0.0.1:8080/test 进行测试,主要是观察控制台的打印信息。
Hibernate: insert into demo_info (name, pwd, state) values (?, ?, ?)
没有走缓存!52
DemoInfo [id=52, name=张三, pwd=123456, state=0]
DemoInfo [id=52, name=张三, pwd=123456, state=0]
Hibernate: insert into demo_info (name, pwd, state) values (?, ?, ?)
没有走缓存!53
DemoInfo [id=53, name=李四, pwd=123456, state=0]
DemoInfo [id=53, name=李四, pwd=123456, state=0]
============修改数据=====================
DemoInfo [id=53, name=李四-updated, pwd=123456, state=0]
DemoInfo [id=53, name=李四-updated, pwd=123456, state=0]
C:\Users\ADMINI~1.ANG\AppData\Local\Temp\
Hibernate: insert into demo_info (name, pwd, state) values (?, ?, ?)
没有走缓存!54
DemoInfo [id=54, name=张三, pwd=123456, state=0]
DemoInfo [id=54, name=张三, pwd=123456, state=0]
Hibernate: insert into demo_info (name, pwd, state) values (?, ?, ?)
没有走缓存!55
DemoInfo [id=55, name=李四, pwd=123456, state=0]
DemoInfo [id=55, name=李四, pwd=123456, state=0]
============修改数据=====================
DemoInfo [id=55, name=李四-updated, pwd=123456, state=0]
DemoInfo [id=55, name=李四-updated, pwd=123456, state=0]
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?????? 好了本篇文章就写到这里吧,打烊休息了,实在是动不了!
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Spring Boot 系列博客】
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0)前言【从零开始学Spring Boot】 :
http://412887952-qq-com.iteye.com/blog/2291496
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(1)spring boot起步之Hello World【从零开始学Spring Boot】:
http://412887952-qq-com.iteye.com/blog/2291500
(2)Spring Boot返回json数据【从零开始学Spring Boot】
http://412887952-qq-com.iteye.com/blog/2291508
(15)Spring Boot使用Druid和监控配置【从零开始学Spring Boot】
http://412887952-qq-com.iteye.com/blog/2292362
16)Spring Boot使用Druid(编程注入)【从零开始学Spring Boot】
http://412887952-qq-com.iteye.com/blogs/2292376
(17)Spring Boot普通类调用bean【从零开始学Spring Boot】:
http://412887952-qq-com.iteye.com/blog/2292388
......
(35)Spring Boot集成Redis实现缓存机制【从零开始学Spring Boot】
http://412887952-qq-com.iteye.com/blog/2294942
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更多查看博客:http://412887952-qq-com.iteye.com/
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(37)Spring Boot集成EHCache实现缓存机制【从零开始学Spring Boot】
原文:http://412887952-qq-com.iteye.com/blog/2294952