SpringBoot如何使用Scala進行開發的實現
阿新 • • 發佈：2020-01-07
Scala是一門多正規化的程式語言，一種類似Java的程式語言，設計初衷是實現可伸縮的語言並整合面向物件程式設計。Scala把Erlang風格的基於actor的併發帶進了JVM，開發者可以利用Scala的actor模型在JVM上設計具伸縮性的併發應用程式，它會自動獲得多核心處理器帶來的優勢，而不必依照複雜的Java執行緒模型來編寫程式，接下來就介紹一下如何在SpringBoot框架中使用Scala來進行簡單的Web開發，對scala不瞭解的建議先去學習基礎哦
一、匯入依賴
<?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 https://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>2.2.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.gjing.project</groupId>
<artifactId>scala-demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>scala-demo</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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!--加入Scala依賴庫-->
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.13.1</version>
</dependency>
<dependency>
<groupId>cn.gjing</groupId>
<artifactId>tools-starter-swagger</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>cn.gjing</groupId>
<artifactId>tools-common</artifactId>
<version>1.2.7</version>
</dependency>
</dependencies>
<build>
<plugins>
<!--加入Scala的編譯外掛，否則無法進行編譯-->
<plugin>
<groupId>org.scala-tools</groupId>
<artifactId>maven-scala-plugin</artifactId>
<version>2.15.2</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>通過上面我們可以發現，和建立Java版本的SpringBoot專案沒啥不同，只是引入了scala-library這個我們之前沒引入的包，同時增加了對scala編譯的外掛
二、配置YML檔案
server: port: 8080 spring: application: name: scala-demo datasource: driver-class-name: com.mysql.cj.jdbc.Driver url: jdbc:mysql://127.0.0.1:3306/demo?characterEncoding=utf8&useSSL=false username: root password: root type: com.zaxxer.hikari.HikariDataSource hikari: maximum-pool-size: 5 minimum-idle: 1 idle-timeout: 30000 connection-timeout: 30000 jpa: database: mysql hibernate: ddl-auto: update # 設定創表引擎為Innodb，不然預設為MyiSam database-platform: org.hibernate.dialect.MySQL5InnoDBDialect swagger: base-package: com.gjing.project.scala.controller title: scala學習的demo
三、建立實體類
import javax.persistence._
import scala.beans.BeanProperty
/**
* @author Gjing
**/
@Entity
@Table(name = "scala_customer")
class Customer {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@BeanProperty
var id:Integer = _
@BeanProperty
var customerName:String = _
def this(customerName:String){
this()
this.customerName = customerName
}
override def toString: String = s"Customer($id,$customerName)"
}
這塊和我們用java開發沒啥不同，只是@BeanProperty註解會幫我們生成get和set
四、Repository層
import com.gjing.project.scala.entity.Customer
import org.springframework.data.jpa.repository.JpaRepository
import org.springframework.stereotype.Repository
/**
* @author Gjing
**/
@Repository
trait CustomerRepository extends JpaRepository[Customer,Integer] {
/**
* 通過使用者名稱查詢
* @param name 使用者名稱
* @return Customer
*/
def findByCustomerName(name:String) : Customer
}
這裡和JAVA不同的是泛型採用的是[]中括號，這點要注意
五、Service層
import cn.gjing.tools.common.result.PageResult
import com.gjing.project.scala.entity.Customer
import com.gjing.project.scala.exceptions.MyServiceException
import com.gjing.project.scala.repository.CustomerRepository
import javax.annotation.Resource
import org.springframework.data.domain.Pageable
import org.springframework.stereotype.Service
/**
* @author Gjing
**/
@Service
class CustomerService @Resource()(customerRepository: CustomerRepository) {
/**
* 儲存使用者
*
* @param name 使用者名稱
*/
def saveCustomer(name: String): Unit = {
var customer = customerRepository.findByCustomerName(name)
if (customer != null) {
throw MyServiceException("新增失敗，使用者已存在")
}
customer = new Customer(name)
customerRepository.save(customer)
}
/**
* 分頁查詢
*
* @param pageable 分頁物件
* @return
*/
def pageCustomer(pageable: Pageable): PageResult[java.util.List[Customer]] = {
val page = customerRepository.findAll(pageable)
return PageResult.of(page.getContent,page.getTotalPages,page.getSize,page.getTotalElements,page.getNumber)
}
/**
* 更新使用者名稱
* @param id 使用者id
* @param name 使用者名稱
*/
def updateCustomer(id: Integer,name: String): Unit = {
val customer = customerRepository.findById(id).orElseThrow(() => MyServiceException("更新失敗，使用者不存在"))
customer.setCustomerName(name)
customerRepository.saveAndFlush(customer)
}
/**
* 刪除指定使用者
* @param id 使用者id
*/
def deleteCustomer(id:Integer): Unit = {
val customer = customerRepository.findById(id).orElseThrow(() => MyServiceException("刪除失敗，使用者不存在"))
customerRepository.delete(customer)
}
}
有意思的是，在scala中依賴注入是寫在類名上的
六、Controller層
import cn.gjing.tools.common.annotation.NotEmpty
import cn.gjing.tools.common.result.PageResult
import com.gjing.project.scala.entity.Customer
import com.gjing.project.scala.service.CustomerService
import io.swagger.annotations.{Api,ApiImplicitParam,ApiImplicitParams,ApiOperation}
import javax.annotation.Resource
import org.springframework.data.domain.PageRequest
import org.springframework.http.ResponseEntity
import org.springframework.web.bind.annotation._
/**
* @author Gjing
**/
@RestController
@Api(tags = Array("使用者的相關功能"))
class CustomerController @Resource()(customerService:CustomerService){
@PostMapping(Array("/customer"))
@ApiOperation("新增使用者")
@ApiImplicitParam(name = "customerName",value = "使用者名稱",dataType = "String",required = true,paramType = "query")
@NotEmpty
def saveCustomer(customerName:String): ResponseEntity[String] ={
customerService.saveCustomer(customerName)
ResponseEntity.ok("新增成功")
}
@GetMapping(Array("/customer_page"))
@ApiOperation("分頁查詢")
@ApiImplicitParams(Array(
new ApiImplicitParam(name = "page",value = "頁數",dataType = "int",paramType = "query"),new ApiImplicitParam(name = "size",value = "條數",))
def pageCustomer(page:Integer,size:Integer): ResponseEntity[PageResult[java.util.List[Customer]]]={
ResponseEntity.ok(customerService.pageCustomer(PageRequest.of(page,size)))
}
@NotEmpty
@PutMapping(Array("/customer"))
@ApiOperation("更新使用者")
@ApiImplicitParams(Array(
new ApiImplicitParam(name = "id",value = "使用者ID",new ApiImplicitParam(name = "name",paramType = "query")
))
def updateCustomer(id:Integer,name:String): ResponseEntity[String] = {
customerService.updateCustomer(id,name)
ResponseEntity.ok("修改成功")
}
@DeleteMapping(Array("/customer/{id}"))
@ApiOperation("刪除使用者")
def deleteCustomer(id:Integer): ResponseEntity[String] = {
customerService.deleteCustomer(id)
ResponseEntity.ok("刪除成功")
}
}
這樣我們一個簡單的Scala版本的Web專案就寫好啦，只需要啟動就可以試著執行啦，本文的原始碼地址：scala-demo，有任何不清楚的可以在評論區回覆哈
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支援我們。