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
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• 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>
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• 一个简单的应用类

package com.edurt.ssiimport org.springframework.boot.SpringApplication
import org.springframework.boot.autoconfigure.SpringBootApplication@SpringBootApplication
class SpringBootScalaIntegrationobject SpringBootScalaIntegration extends App{SpringApplication.run(classOf[SpringBootScalaIntegration])}
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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.controllerimport org.springframework.web.bind.annotation.{GetMapping, RestController}@RestController
class HelloController {@GetMapping(value = Array("hello"))def hello(): String = {return "hello,scala"}}
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• 修改SpringBootScalaIntegration文件增加以下设置扫描路径

@ComponentScan(value = Array("com.edurt.ssi.controller"
))
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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>
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• 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"
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• 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>
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• 创建页面转换器HelloView

package com.edurt.ssi.viewimport org.springframework.stereotype.Controller
import org.springframework.web.bind.annotation.GetMapping@Controller
class HelloView {@GetMapping(value = Array("hello_view"))def helloView: String = {return "hello";}}
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• 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>
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• 修改SpringBootScalaIntegration文件增加以下设置扫描model路径

@EntityScan(value = Array("com.edurt.ssi.model"
))
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• 创建User实体

package com.edurt.ssi.modelimport javax.persistence.{Entity, GeneratedValue, Id}@Entity
class UserModel {@Id@GeneratedValuevar id: Long = 0var name: String = null}
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• 创建UserSupport dao数据库操作工具类

package com.edurt.ssi.supportimport com.edurt.ssi.model.UserModel
import org.springframework.data.repository.PagingAndSortingRepositorytrait UserSupport extends PagingAndSortingRepository[UserModel, Long] {}
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• 创建UserService服务类

package com.edurt.ssi.serviceimport com.edurt.ssi.model.UserModeltrait UserService {/*** save model to db*/def save(model: UserModel): UserModel;}
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• 创建UserServiceImpl实现类

package com.edurt.ssi.serviceimport 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)}}
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• 创建用户UserController进行持久化数据

package com.edurt.ssi.controllerimport 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 = namereturn this.userService.save(userModel).id}}
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• 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
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收到返回结果

1
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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]
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• 修改UserServiceImpl增加以下代码

/*** get all model*/
override def getAll(page: Pageable): Page[UserModel] = {return this.userSupport.findAll(page)
}
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• 修改UserController增加以下代码

@GetMapping(value = Array("list"))
def get(): Page[UserModel] = this.userService.getAll(PageRequest.of(0, 10))
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• 创建UserView文件渲染User数据

package com.edurt.ssi.viewimport 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"}}
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• 创建user.mustache文件渲染数据(自行解析返回数据即可)

{{users}}
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• 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>
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• 创建UserServiceTest文件进行测试UserService功能

package com.edurt.ssiimport 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) {@Testdef `get all`() {println(">> Assert blog page title, content and status code")val entity = this.userService.getAll(PageRequest.of(0, 1))print(entity.getTotalPages)}}
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源码地址：GitHub