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今天我们尝试 Kotlin 整合 Vertx，并决定建立一个非常简单的 Web 应用程序，使用 Kotlin 和 Vertx 作为编程语言进行编码构建。
生成项目
打开控制台窗口执行以下代码进行生成一个 maven 项目
mvn archetype:generate -DgroupId=com.edurt.kvi -DartifactId=kotlin-vertx-integration -DarchetypeArtifactId=maven-archetype-quickstart -Dversion=1.0.0 -DinteractiveMode=false
修改 pom.xml 增加 java 和 kotlin 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.kvi</groupId>
<artifactId>kotlin-vertx-integration</artifactId>
<packaging>jar</packaging>
<version>1.0.0</version>
<name>kotlin-vertx-integration</name>
<description>Kotlin Vertx Integration is a open source kotlin vertx integration example.</description>
<!– properties –>
<properties>
<!– dependency –>
<dependency.kotlin.version>1.2.71</dependency.kotlin.version>
<dependency.vertx.ersion>3.4.1</dependency.vertx.ersion>
<!– plugin –>
<plugin.maven.compiler.version>3.3</plugin.maven.compiler.version>
<plugin.maven.javadoc.version>2.10.4</plugin.maven.javadoc.version>
<plugin.maven.kotlin.version>1.2.71</plugin.maven.kotlin.version>
<!– environment –>
<environment.compile.java.version>1.8</environment.compile.java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<jvmTarget>1.8</jvmTarget>
</properties>
<!– dependencys –>
<dependencies>
<!– kotlin –>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib-jdk8</artifactId>
<version>${dependency.kotlin.version}</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-reflect</artifactId>
<version>${dependency.kotlin.version}</version>
</dependency>
<!– vertx –>
<dependency>
<groupId>io.vertx</groupId>
<artifactId>vertx-core</artifactId>
<version>${dependency.vertx.ersion}</version>
</dependency>
<dependency>
<groupId>io.vertx</groupId>
<artifactId>vertx-web</artifactId>
<version>${dependency.vertx.ersion}</version>
</dependency>
</dependencies>
<!– prerequisites –>
<prerequisites>
<maven>3.5.0</maven>
</prerequisites>
<!– build –>
<build>
<sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
<testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
<plugins>
<plugin>
<artifactId>kotlin-maven-plugin</artifactId>
<groupId>org.jetbrains.kotlin</groupId>
<configuration>
<args>
<arg>-Xjsr305=strict</arg>
</args>
<compilerPlugins>
<plugin>spring</plugin>
<plugin>jpa</plugin>
<plugin>all-open</plugin>
</compilerPlugins>
<pluginOptions>
<option>all-open:annotation=javax.persistence.Entity</option>
</pluginOptions>
</configuration>
<dependencies>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-allopen</artifactId>
<version>${plugin.maven.kotlin.version}</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-noarg</artifactId>
<version>${plugin.maven.kotlin.version}</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>kapt</id>
<goals>
<goal>kapt</goal>
</goals>
<configuration>
<sourceDirs>
<sourceDir>src/main/kotlin</sourceDir>
</sourceDirs>
<annotationProcessorPaths>
<annotationProcessorPath>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<version>${project.parent.version}</version>
</annotationProcessorPath>
</annotationProcessorPaths>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>${plugin.maven.compiler.version}</version>
<configuration>
<source>${environment.compile.java.version}</source>
<target>${environment.compile.java.version}</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-javadoc-plugin</artifactId>
<version>${plugin.maven.javadoc.version}</version>
<configuration>
<aggregate>true</aggregate>
<!– custom tags –>
<tags>
<tag>
<name>Description</name>
<placement>test</placement>
<head>description</head>
</tag>
</tags>
<!– close jdoclint check document –>
<additionalparam>-Xdoclint:none</additionalparam>
</configuration>
</plugin>
</plugins>
</build>
</project>
添加 Vertx 实例
创建 CoreVerticle 类文件
package com.edurt.kvi.core
import io.vertx.core.AbstractVerticle
import io.vertx.core.Future
import io.vertx.core.Handler
import io.vertx.ext.web.Router
import io.vertx.ext.web.RoutingContext
class CoreVerticle : AbstractVerticle() {
override fun start(startFuture: Future<Void>?) {
val router = createRouter()
val port = config().getInteger(“http.port”, 8080)
vertx.createHttpServer()
.requestHandler {router.accept(it) }
.listen(port) {result ->
if (result.succeeded()) {
startFuture?.complete()
} else {
startFuture?.fail(result.cause())
}
}
}
private fun createRouter() = Router.router(vertx).apply {
get(“/”).handler(handlerRoot)
}
/**
* create router instance
*/
val handlerRoot = Handler<RoutingContext> {req ->
req.response().end(“Hello Kotlin Vertx Integration!”)
}
}
设置启动类
package com.edurt.kvi
import com.edurt.kvi.core.CoreVerticle
import io.vertx.core.Vertx
class KotlinVertxIntegration
fun main(args: Array<String>) {
val vertx = Vertx.vertx()
vertx.deployVerticle(CoreVerticle::class.java.name)
}
以上操作在 vertx.deployVerticle 阶段执行了部署 Verticle 的操作，即部署 CoreVerticle。
启动应用后浏览器访问 http://localhost:8080 出现以下页面
增加页面渲染功能
修改 pom.xml 文件增加页面依赖
<dependency.slf4j.version>1.7.25</dependency.slf4j.version>
<dependency>
<groupId>io.vertx</groupId>
<artifactId>vertx-web-templ-thymeleaf</artifactId>
<version>${dependency.vertx.ersion}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${dependency.slf4j.version}</version>
</dependency>
增加页面渲染文件
package com.edurt.kvi.router
import io.vertx.ext.web.Router
import io.vertx.ext.web.RoutingContext
import io.vertx.ext.web.templ.ThymeleafTemplateEngine
import org.thymeleaf.templatemode.TemplateMode
class HomeViewRouter
fun index(r: Router) {
val engine = ThymeleafTemplateEngine.create().setMode(TemplateMode.HTML)
r.get(“/index.html”).handler {c ->
render(c, engine, “templates/index.html”)
}
}
fun render(c: RoutingContext, engine: ThymeleafTemplateEngine, templ: String) {
engine.render(c, templ) {res ->
if (res.succeeded()) {
c.response().end(res.result())
} else {
c.fail(res.cause())
}
}
}
在 templates/index.html 目录下创建页面文件
<!DOCTYPE html SYSTEM “http://www.thymeleaf.org/dtd/xhtml1-strict-thymeleaf-4.dtd”>
<html xmlns=”http://www.w3.org/1999/xhtml”>
<head>
<title>Kotlin Vertx Integration</title>
<meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8″/>
</head>
<body>
<p>Welcome To Kotlin Vertx Integration!</p>
</body>
</html>
修改 CoreVerticle 增加页面跳转
package com.edurt.kvi.core
import com.edurt.kvi.router.index
import io.vertx.core.AbstractVerticle
import io.vertx.core.Future
import io.vertx.core.Handler
import io.vertx.core.Vertx
import io.vertx.core.http.HttpServerResponse
import io.vertx.ext.web.Router
import io.vertx.ext.web.RoutingContext
class CoreVerticle : AbstractVerticle() {
override fun start() {
val router = createRouter(vertx)
// go to index page
index(router)
vertx.createHttpServer().requestHandler { handler -> router.accept(handler) }.listen(8080)
// val port = config().getInteger(“http.port”, 8080)
// vertx.createHttpServer()
// .requestHandler {router.accept(it) }
// .listen(port) {result ->
// if (result.succeeded()) {
// startFuture?.complete()
// } else {
// startFuture?.fail(result.cause())
// }
// }
}
private fun createRouter() = Router.router(vertx).apply {
get(“/”).handler(handlerRoot)
}
/**
* create router instance
*/
val handlerRoot = Handler<RoutingContext> {req ->
req.response().end(“Hello Kotlin Vertx Integration!”)
}
fun createRouter(v: Vertx): Router {
var router = Router.router(v)
router.route(“/”).handler {c -> c.response().end(“Hello Kotlin Vertx Integration!”) }
router.route(“/index”).handler {c -> c.response().html().end(“Hello Kotlin Vertx Integration Page!”) }
return router
}
fun HttpServerResponse.html(): HttpServerResponse {
return this.putHeader(“content-type”, “text/html”)
}
}
启动应用后浏览器访问 http://localhost:8080/index.html 出现以下页面