数据库
- 创建数据库 db01
CREATE TABLE dept(
deptno BIGINT NOT NULL PRIMARY KEY AUTO_INCREMENT,
dname VARCHAR(60),
db_source VARCHAR(60)
);
INSERT INTO dept(dname,db_source) VALUES('开发部',DATABASE());
INSERT INTO dept(dname,db_source) VALUES('人事部',DATABASE());
INSERT INTO dept(dname,db_source) VALUES('财务部',DATABASE());
INSERT INTO dept(dname,db_source) VALUES('市场部',DATABASE());
INSERT INTO dept(dname,db_source) VALUES('运维部',DATABASE());
SELECT * FROM dept;
1. 创建父工程,进行依赖管理
<dependencyManagement>
<dependencies>
<!--springcloud依赖-->
<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-dependencies -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Hoxton.SR8</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!--springboot依赖-->
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-dependencies -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>2.4.3</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!--数据库-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.23</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.2.5</version>
</dependency>
<!--springboot启动器-->
<!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.4</version>
</dependency>
<!--junit-->
<!-- https://mvnrepository.com/artifact/junit/junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
</dependency>
<!--lombok-->
<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>${lombok.version}</version>
</dependency>
<!--log4j-->
<!-- https://mvnrepository.com/artifact/log4j/log4j -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
<!--logback-->
<!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-core -->
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.2.3</version>
</dependency>
</dependencies>
</dependencyManagement>
- spring-cloud-dependencies和spring-boot-dependencies的作用范围设置为:< scope>import< /scope>,这样其他的相关插件的版本就可以根据cloud和boot的版本自动导入
2. 建立第一个 api Moudle,存放实体类,模拟一个服务器
- 导入所需要的依赖
<!--当前module所需要的依赖-->
<dependencies>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
</dependencies>
- 编写实体类
@Data
@NoArgsConstructor
public class Dept implements Serializable {
private long deptno;
private String dname;
//来自哪个数据库,因为微服务架构可以一个服务对应一个数据库,同一个信息被存到多个不同的数据库
private String db_source;
public Dept(String dname){
this.dname = dname;
}
}
- tips:开启链式写法
//@Accessors(chain = true) 开启链式写法
/**
*链式写法
* user.setId(1).setName("qk").setGender("男")
*/
- 为了安全,实体类要序列化,实现Serializable接口
implements Serializable
3. 建立第二个 provider Moudle,存放mapper、service和controller三层,模拟一个服务器
- 导入模块所需依赖(通过pom坐标,引入第一个Moudle)
<dependencies>
<!--引入自定义的模块,我们就可以使用这个模块中的类了-->
<dependency>
<groupId>com.qk</groupId>
<artifactId>springcloud-01-api</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jetty</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-test</artifactId>
</dependency>
<!-- spring-boot-devtools -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
</dependency>
</dependencies>
- mapper层
@Mapper
@Repository
public interface DeptMapper {
public boolean addDept(Dept dept); //添加一个部门
public Dept queryById(Long id); //根据id查询部门
public List<Dept> queryAll(); //查询所有部门
}
- mapper映射文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.qk.springcloud.mapper.DeptMapper">
<insert id="addDept" parameterType="Dept">
insert into dept (dname,db_source) values (#{dname},DATABASE());
</insert>
<select id="queryById" resultType="Dept" parameterType="Long">
select deptno,dname,db_source from dept where deptno = #{deptno};
</select>
<select id="queryAll" resultType="Dept">
select deptno,dname,db_source from dept;
</select>
</mapper>
- service层
public interface DeptService {
public boolean addDept(Dept dept); //添加一个部门
public Dept queryById(Long id); //根据id查询部门
public List<Dept> queryAll(); //查询所有部门
}
- service层实现类
@Service
public class DeptServiceImpl implements DeptService{
//自动注入
@Autowired
private DeptMapper deptMapper;
@Override
public boolean addDept(Dept dept) {
return deptMapper.addDept(dept);
}
@Override
public Dept queryById(Long id) {
return deptMapper.queryById(id);
}
@Override
public List<Dept> queryAll() {
return deptMapper.queryAll();
}
}
- springboot配置文件
server:
port: 8001
mybatis:
type-aliases-package: com.qk.springcloud.pojo #扫描api Moudle 下的实体类
mapper-locations: classpath:mybatis/mapper/*.xml #扫描provider Moudle 下的实体类映射文件
spring:
application:
name: springcloud-provider-dept #给项目起个名字
datasource:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/db01?useUnicode=true&characterEncoding=utf-8
username: root
password: root
- 编写springboot主启动类
@SpringBootApplication
public class DeptProvider_8001 {
public static void main(String[] args) {
SpringApplication.run(DeptProvider_8001.class,args);
}
}
- 可以编写controller层,进行测试检验前两个Moudle是否可以顺利调用
@RestController
@RequestMapping("/dept")
public class DeptController {
@Autowired
private DeptService service;
// @RequestBody
// 如果参数是放在请求体中,传入后台的话,那么后台要用@RequestBody才能接收到
@PostMapping("/add")
public boolean addDept(Dept dept) {
return service.addDept(dept);
}
@GetMapping("/get/{id}")
public Dept get(@PathVariable("id") Long id) {
return service.queryById(id);
}
@GetMapping("/list")
public List<Dept> queryAll() {
return service.queryAll();
}
}
4. 建立第三个 consumer Moudle,调用第二个服务器的service层,模拟一个服务器
- 端口配置
server:
port: 80
- 编写controller层
- RestTemplate 需要自己配置,再注入
@RestController
@RequestMapping("/consumer")
public class DeptConsumerController {
//理解:消费者,不应该有service层
// 远程调用 调用http://localhost:8001下的数据
// 使用RestTemplate访问restful接口非常的简单粗暴且无脑,提供多种便捷访问远程http服务的方法,简单的restful服务模板
// getForObject (请求地址 , 实体 ,响应类型)
// (url,requestMap,ResponseBean.class) 这三个参数分别代表
// REST请求地址,请求参数,Http响应转换 被 转换成的对象类型
@Autowired
private RestTemplate restTemplate;
private static final String REST_URL_PREFIX = "http://localhost:8001";
@RequestMapping("/dept/add")
public boolean add(Dept dept){
return restTemplate.postForObject(REST_URL_PREFIX+"/dept/add",dept,Boolean.class);
}
@RequestMapping("/dept/get/{id}")
public Dept get(@PathVariable("id") Long id){
return restTemplate.getForObject(REST_URL_PREFIX+"/dept/get/"+id,Dept.class);
}
@RequestMapping("/dept/list")
public List<Dept> list(){
return restTemplate.getForObject(REST_URL_PREFIX+"/dept/list",List.class);
}
}
- 获取 RestTemplate
@Configuration
public class RestTemplateBean {
@Bean
public RestTemplate getRestTemplate(){
return new RestTemplate();
}
}
- 在SpringCloud中,远程调用需要使用RestTemplate
- RestTemplate提供了多种便捷访问远程Http服务的方法,是一种简单便捷的访问restful服务模板
类,是Spring提供的用于访问Rest服务的客户端模板工具集 - 使用RestTemplate访问restful接口非常的简单,(url,requsetMap,ResponseBean.class) 三个参数分别代表REST请求地址,请求参数,Http响应转换 被 转换成的对象类型
- 编写主启动类
@SpringBootApplication
public class DeptConsumer_80 {
public static void main(String[] args) {
SpringApplication.run(DeptConsumer_80.class,args);
}
}
5. 完毕
对比
- RPC(Dubbo+Zookeeper):
需要暴露接口,消费者有生产者相同的接口,通过@Reference远程引用生产者的service - SpringCloud
只需要知道远程的url地址,通过RestTemplate的get或post等方法去请求调用service层的方法