今天我们尝试 Spring Boot 整合 Scala，并决定建立一个非常简单的 Spring Boot 微服务，使用 Scala 作为编程语言进行编码构建。
创建项目
初始化项目
mvn archetype:generate -DgroupId=com.edurt.ssi -DartifactId=springboot-scala-integration -DarchetypeArtifactId=maven-archetype-quickstart -Dversion=1.0.0 -DinteractiveMode=false
修改 pom.xml 增加 java 和 scala 的支持
<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/maven-v4_0_0.xsd”>
<modelVersion>4.0.0</modelVersion>
<groupId>com.edurt.ssi</groupId>
<artifactId>springboot-scala-integration</artifactId>
<packaging>jar</packaging>
<version>1.0.0</version>
<name>springboot-scala-integration</name>
<description>SpringBoot Scala Integration is a open source springboot, scala integration example.</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
<relativePath/> <!– lookup parent from repository –>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<!– dependency config –>
<dependency.scala.version>2.12.1</dependency.scala.version>
<!– plugin config –>
<plugin.maven.scala.version>3.1.3</plugin.maven.scala.version>
</properties>
<dependencies>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>${dependency.scala.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<sourceDirectory>${project.basedir}/src/main/scala</sourceDirectory>
<testSourceDirectory>${project.basedir}/src/test/scala</testSourceDirectory>
<plugins>
<plugin>
<groupId>net.alchim31.maven</groupId>
<artifactId>scala-maven-plugin</artifactId>
<version>${plugin.maven.scala.version}</version>
<executions>
<execution>
<goals>
<goal>compile</goal>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
一个简单的应用类
package com.edurt.ssi
import org.springframework.boot.SpringApplication
import org.springframework.boot.autoconfigure.SpringBootApplication
@SpringBootApplication
class SpringBootScalaIntegration
object SpringBootScalaIntegration extends App{
SpringApplication.run(classOf[SpringBootScalaIntegration])
}
添加 Rest API 接口功能
创建一个 HelloController Rest API 接口, 我们只提供一个简单的 get 请求获取 hello,scala 输出信息
package com.edurt.ssi.controller
import org.springframework.web.bind.annotation.{GetMapping, RestController}
@RestController
class HelloController {
@GetMapping(value = Array(“hello”))
def hello(): String = {
return “hello,scala”
}
}
修改 SpringBootScalaIntegration 文件增加以下设置扫描路径
@ComponentScan(value = Array(
“com.edurt.ssi.controller”
))
添加页面功能
修改 pom.xml 文件增加以下页面依赖
<!– mustache –>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-mustache</artifactId>
</dependency>
修改 SpringBootScalaIntegration 文件增加以下设置扫描路径 ComponentScan 的 value 字段中
“com.edurt.ssi.view”
在 src/main/resources 路径下创建 templates 文件夹
在 templates 文件夹下创建一个名为 hello.mustache 的页面文件
<h1>Hello, Scala</h1>
创建页面转换器 HelloView
package com.edurt.ssi.view
import org.springframework.stereotype.Controller
import org.springframework.web.bind.annotation.GetMapping
@Controller
class HelloView {
@GetMapping(value = Array(“hello_view”))
def helloView: String = {
return “hello”;
}
}
浏览器访问 http://localhost:8080/hello_view 即可看到页面内容
添加数据持久化功能
修改 pom.xml 文件增加以下依赖 (由于测试功能我们使用 h2 内存数据库)
<!– data jpa and db –>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
修改 SpringBootScalaIntegration 文件增加以下设置扫描 model 路径
@EntityScan(value = Array(
“com.edurt.ssi.model”
))
创建 User 实体
package com.edurt.ssi.model
import javax.persistence.{Entity, GeneratedValue, Id}
@Entity
class UserModel {
@Id
@GeneratedValue
var id: Long = 0
var name: String = null
}
创建 UserSupport dao 数据库操作工具类
package com.edurt.ssi.support
import com.edurt.ssi.model.UserModel
import org.springframework.data.repository.PagingAndSortingRepository
trait UserSupport extends PagingAndSortingRepository[UserModel, Long] {
}
创建 UserService 服务类
package com.edurt.ssi.service
import com.edurt.ssi.model.UserModel
trait UserService {
/**
* save model to db
*/
def save(model: UserModel): UserModel;
}
创建 UserServiceImpl 实现类
package com.edurt.ssi.service
import com.edurt.ssi.model.UserModel
import com.edurt.ssi.support.UserSupport
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.stereotype.Service
@Service(value = “userService”)
class UserServiceImpl @Autowired() (
val userSupport: UserSupport
) extends UserService {
/**
* save model to db
*/
override def save(model: UserModel): UserModel = {
return this.userSupport.save(model)
}
}
创建用户 UserController 进行持久化数据
package com.edurt.ssi.controller
import com.edurt.ssi.model.UserModel
import com.edurt.ssi.service.UserService
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.web.bind.annotation.{PathVariable, PostMapping, RequestMapping, RestController}
@RestController
@RequestMapping(value = Array(“user”))
class UserController @Autowired()(
val userService: UserService
) {
@PostMapping(value = Array(“save/{name}”))
def save(@PathVariable name: String): Long = {
val userModel = {
new UserModel()
}
userModel.name = name
return this.userService.save(userModel).id
}
}
使用控制台窗口执行以下命令保存数据
curl -X POST http://localhost:8080/user/save/qianmoQ
收到返回结果
1
表示数据保存成功
增加数据读取渲染功能
修改 UserService 增加以下代码
/**
* get all model
*/
def getAll(page: Pageable): Page[UserModel]
修改 UserServiceImpl 增加以下代码
/**
* get all model
*/
override def getAll(page: Pageable): Page[UserModel] = {
return this.userSupport.findAll(page)
}
修改 UserController 增加以下代码
@GetMapping(value = Array(“list”))
def get(): Page[UserModel] = this.userService.getAll(PageRequest.of(0, 10))
创建 UserView 文件渲染 User 数据
package com.edurt.ssi.view
import com.edurt.ssi.service.UserService
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.data.domain.PageRequest
import org.springframework.stereotype.Controller
import org.springframework.ui.Model
import org.springframework.web.bind.annotation.GetMapping
@Controller
class UserView @Autowired()(
private val userService: UserService
) {
@GetMapping(value = Array(“user_view”))
def helloView(model: Model): String = {
model.addAttribute(“users”, this.userService.getAll(PageRequest.of(0, 10)))
return “user”
}
}
创建 user.mustache 文件渲染数据 (自行解析返回数据即可)
{{users}}
浏览器访问 http://localhost:8080/user_view 即可看到页面内容
增加单元功能
修改 pom.xml 文件增加以下依赖
<!– test –>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</exclusion>
<exclusion>
<groupId>org.mockito</groupId>
<artifactId>mockito-core</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<scope>test</scope>
</dependency>
创建 UserServiceTest 文件进行测试 UserService 功能
package com.edurt.ssi
import com.edurt.ssi.service.UserService
import org.junit.jupiter.api.Test
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.boot.test.context.SpringBootTest
import org.springframework.data.domain.PageRequest
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
class UserServiceTest @Autowired()(
private val userService: UserService) {
@Test
def `get all`() {
println(“>> Assert blog page title, content and status code”)
val entity = this.userService.getAll(PageRequest.of(0, 1))
print(entity.getTotalPages)
}
}
源码地址：GitHub