使用kotlin集成springboot开发的超详细教程

第使用kotlin集成springboot开发的超详细教程目录一、安装支持插件二、maven配置注意三、创建入口函数类四、编写入口函数五、创建数据库对象六、创建仓库操作接口七、创建一个业务接口来声明业务八、创建一个业务接口实现来实现声明的业务九、创建一个http服务接口目前大多数都在使用java集成springboot进行开发，本文演示仅仅将java换成kotlin，其他不变的情况下进行开发。

一、安装支持插件

在idea中安装kotlin插件（大多数情况下会默认安装了）

二、maven配置注意

kotlin目前不支持lombok所以不能使用或引用lombok相关的插件或依赖包，下面是一个排除示例，同时也不支持maven-enforcer-plugin

dependency

groupIdmon/groupId

artifactIda-common/artifactId

version1.0.0-SNAPSHOT/version

exclusions

exclusion

groupIdjectlombok/groupId

artifactIdlombok/artifactId

/exclusion

/exclusions

/dependency

maven的属性配置

properties

project.build.sourceEncodingUTF-8/project.build.sourceEncoding

project.reporting.outputEncodingUTF-8/project.reporting.outputEncoding

java.version1.8/java.version

piler.source1.8/piler.source

piler.target1.8/piler.target

kotlin.version1.3.21/kotlin.version

!--增量编译--

piler.incrementaltrue/piler.incremental

!--关闭协程编译警告--

experimentalCoroutinesenable/experimentalCoroutines

spring-boot.version2.2.4.RELEASE/spring-boot.version

spring-cloud.versionHoxton.SR1/spring-cloud.version

swagger.version2.7.0/swagger.version

main.classcom.lc.github.KotlinDemoApplication/main.class

querydsl.version4.2.1/querydsl.version

mapstruct.version1.3.1.Final/mapstruct.version

/properties

必要的依赖

dependencies

!--反射支持包，不需要可以去掉--

dependency

groupIdorg.jetbrains.kotlin/groupId

artifactIdkotlin-reflect/artifactId

version${kotlin.version}/version

/dependency

!--jdk8下的kotlin支持包--

dependency

groupIdorg.jetbrains.kotlin/groupId

artifactIdkotlin-stdlib-jdk8/artifactId

version${kotlin.version}/version

/dependency

/dependencies

编译部分

build

plugins

plugin

groupIdorg.jetbrains.kotlin/groupId

artifactIdkotlin-maven-plugin/artifactId

configuration

correctErrorTypestrue/correctErrorTypes

languageVersion${kotlin.language.version}/languageVersion

/configuration

dependencies

dependency

groupIdorg.jetbrains.kotlin/groupId

artifactIdkotlin-maven-allopen/artifactId

version${kotlin.version}/version

/dependency

/dependencies

executions

execution

idkapt/id

goals

goalkapt/goal

/goals

configuration

correctErrorTypestrue/correctErrorTypes

sourceDirs

sourceDirsrc/main/kotlin/sourceDir

sourceDirsrc/main/java/sourceDir

/sourceDirs

annotationProcessorPaths

annotationProcessorPath

groupIdcom.google.dagger/groupId

artifactIddagger-compiler/artifactId

version2.9/version

/annotationProcessorPath

annotationProcessorPath

groupIdcom.querydsl/groupId

artifactIdquerydsl-apt/artifactId

version${querydsl.version}/version

classifierjpa/classifier

/annotationProcessorPath

annotationProcessorPath

groupIdorg.mapstruct/groupId

artifactIdmapstruct-processor/artifactId

version${mapstruct.version}/version

/annotationProcessorPath

/annotationProcessorPaths

/configuration

/execution

execution

idcompile/id

goals

goalcompile/goal

/goals

configuration

sourceDirs

sourceDirsrc/main/kotlin/sourceDir

sourceDirsrc/main/java/sourceDir

/sourceDirs

/configuration

/execution

execution

idtest-kapt/id

goals

goaltest-kapt/goal

/goals

configuration

sourceDirs

sourceDirsrc/test/kotlin/sourceDir

sourceDirsrc/test/java/sourceDir

/sourceDirs

annotationProcessorPaths

annotationProcessorPath

groupIdcom.google.dagger/groupId

artifactIddagger-compiler/artifactId

version2.9/version

/annotationProcessorPath

annotationProcessorPath

groupIdcom.querydsl/groupId

artifactIdquerydsl-apt/artifactId

version${querydsl.version}/version

classifierjpa/classifier

/annotationProcessorPath

annotationProcessorPath

groupIdorg.mapstruct/groupId

artifactIdmapstruct-processor/artifactId

version${mapstruct.version}/version

/annotationProcessorPath

/annotationProcessorPaths

/configuration

/execution

execution

idtest-compile/id

goals

goaltest-compile/goal

/goals

configuration

sourceDirs

sourceDirsrc/test/kotlin/sourceDir

sourceDirsrc/test/java/sourceDir

sourceDirtarget/generated-sources/kapt/test/sourceDir

/sourceDirs

/configuration

/execution

/executions

/plugin

plugin

groupIdorg.apache.maven.plugins/groupId

artifactIdmaven-compiler-plugin/artifactId

version3.8.1/version

configuration

procnone/proc

source${java.version}/source

target${java.version}/target

annotationProcessorPaths

path

groupIdjectlombok/groupId

artifactIdlombok/artifactId

version${lombok.version}/version

/path

path

groupIdorg.mapstruct/groupId

artifactIdmapstruct-processor/artifactId

version${mapstruct.version}/version

/path

/annotationProcessorPaths

compilerArgs

arg-Amapstruct.suppressGeneratorTimestamp=true/arg

arg-Amapstruct.defaultComponentModel=spring/arg

/compilerArgs

/configuration

executions

!--Replacingdefault-compileasitistreatedspeciallybymaven--

execution

iddefault-compile/id

phasenone/phase

/execution

!--Replacingdefault-testCompileasitistreatedspeciallybymaven--

execution

iddefault-testCompile/id

phasenone/phase

/execution

execution

idjava-compile/id

phasecompile/phase

goals

goalcompile/goal

/goals

/execution

execution

idjava-test-compile/id

phasetest-compile/phase

goals

goaltestCompile/goal

/goals

/execution

/executions

/plugin

plugin

groupIdorg.apache.maven.plugins/groupId

artifactIdmaven-assembly-plugin/artifactId

version2.6/version

executions

execution

idmake-assembly/id

phasepackage/phase

goals

goalsingle/goal

/goals

configuration

archive

manifest

mainClass${main.class}/mainClass

/manifest

/archive

descriptorRefs

descriptorRefjar-with-dependencies/descriptorRef

/descriptorRefs

/configuration

/execution

/executions

/plugin

/plugins

/build

有java与kotlin混合的情况，在上面的plugins下加入下面的编译插件

plugin

groupIdorg.apache.maven.plugins/groupId

artifactIdmaven-compiler-plugin/artifactId

version3.8.1/version

configuration

procnone/proc

source${java.version}/source

target${java.version}/target

annotationProcessorPaths

path

groupIdorg.mapstruct/groupId

artifactIdmapstruct-processor/artifactId

version${mapstruct.version}/version

/path

/annotationProcessorPaths

compilerArgs

arg-Amapstruct.suppressGeneratorTimestamp=true/arg

arg-Amapstruct.defaultComponentModel=spring/arg

/compilerArgs

/configuration

executions

!--Replacingdefault-compileasitistreatedspeciallybymaven--

execution

iddefault-compile/id

phasenone/phase

/execution

!--Replacingdefault-testCompileasitistreatedspeciallybymaven--

execution

iddefault-testCompile/id

phasenone/phase

/execution

execution

idjava-compile/id

phasecompile/phase

goals

goalcompile/goal

/goals

/execution

execution

idjava-test-compile/id

phasetest-compile/phase

goals

goaltestCompile/goal

/goals

/execution

/executions

/plugin

此maven配置集成了querydsl、mapstruct、dagger2的编译，基本上能满足常规的使用

三、创建入口函数类

四、编写入口函数

springboot的启动方法及swagger的配置

@EnableAsync

@EnableSwagger2

@EnableScheduling

@SpringBootApplication

classKotlinDemoApplication:CommandLineRunner{

companionobject{

@JvmStatic

funmain(args:ArrayString){

SpringApplication.run(KotlinDemoApplication::class.java,*args)

@Bean

funapi():Docket{

returnDocket(DocumentationType.SWAGGER_2)

.ignoredParameterTypes(Session::class.java)

.select()

//.apis(RequestHandlerSelectors.any())

.apis(RequestHandlerSelectors.basePackage("com.ayouran.flow.controllers"))

.paths(PathSelectors.any())

.build()

.apiInfo(ApiInfoBuilder()

.description("ayouram-flow相关API")

.title("ayouram-flow")

.version("1.0")

.build())

.pathMapping("/")

overridefunrun(varargargs:String){

println("***************************ok***********************************")

}

五、创建数据库对象

importcom.fasterxml.jackson.annotation.JsonFormat

importorg.hibernate.annotations.DynamicInsert

importorg.hibernate.annotations.DynamicUpdate

importjava.util.*

importjavax.persistence.*

/****

*设备流量规则

@Entity

@Table(name="device_rules",

indexes=[Index(name="device_no",columnList="device_no"),

Index(name="rules_no",columnList="rules_no"),

Index(name="deleted",columnList="deleted")],

uniqueConstraints=[UniqueConstraint(name="device_no_rules_no",columnNames=["device_no","rules_no"])])

@DynamicUpdate

@DynamicInsert

classDeviceRules{

@Column(name="id",columnDefinition="bigint(20)COMMENT'ID,自增'")

@GeneratedValue(strategy=GenerationType.IDENTITY)

varid:Long=null

@Column(name="device_no",columnDefinition="varchar(18)COMMENT'设备编号'")

vardeviceNo:String=null

@Column(name="rules_no",columnDefinition="varchar(18)COMMENT'规则编号'")

varrulesNo:String=null

@JsonFormat(pattern="yyyy-MM-ddHH:mm:ss",timezone="GMT+8")

@Column(name="create_at",columnDefinition="datetimeCOMMENT'创建时间'")

varcreateAt:Date=null

@Column(name="update_at",columnDefinition="datetimeCOMMENT'修改时间'")

varupdateAt:Date=null

*触发jpaupdate代码需要执行的逻辑

@PreUpdate

funpreUpdate(){

updateAt=Date()

*自动设置必要字段的值

@PrePersist

funprePersist(){

updateAt=Date()

createAt=updateAt

deleted=BaseEnum.NOT_REMOVE.index

}

注解使用了hibernate的功能主要用于自动创建/更新表结构以及索引的生成，如果需要mybatis版本的，只需要去掉这里面的注释就好。

六、创建仓库操作接口

基于springboot-data-jpa的repository

@Repository

interfaceDeviceRulesRepository:JpaRepositoryDeviceRules,Long,

JpaSpecificationExecutorDeviceRules,QuerydslPredicateExecutorDeviceRules{

fungetAllByDeviceNoAndDeleted(deviceNo:String,deleted:Int):OptionalMutableListDeviceRules

}

七、创建一个业务接口来声明业务

interfaceDeviceService{

*查询设备的路由规则

funqueryDeviceFlowRules(aPageRequest:APageRequest):PageResultQueryDeviceFlowRulesVO

}

八、创建一个业务接口实现来实现声明的业务

@Service

classDeviceServiceImpl@Autowired

constructor(privatevaldeviceRepository:DeviceRepository,

privatevaldeviceRulesRepository:DeviceRulesRepository,

privatevalquerydslUtlis:QuerydslUtlis,

privatevaldeviceMapstruct:DeviceMapstruct):DeviceService{

privatevallogger=LoggerFactory.getLogger(javaClass)

overridefunqueryDeviceFlowRules(aPageRequest:APageRequest):PageResultQueryDeviceFlowRulesVO{

valqDeviceRules=QDeviceRules.deviceRules

valqFlowRules=QFlowRules.flowRules

varrredicate:Predicate=null

if(StringUtils.isNotBlank(aPageRequest.query))rredicate=qDeviceRules.deviceNo.eq(aPageRequest.query)

valexprs=arrayOfExpression*(qDeviceRules.devic