使用Maven構(gòu)建工具開發(fā)Kotlin Web應(yīng)用程序

1.安裝Maven

下載地址http://maven.apache.org/download.cgi。Windows用戶下載zip包。筆者使用的Maven下載鏈接: http://pan.baidu.com/s/1qYBFZcw 密碼: gmer

下載后的zip包如下

將zip包解壓。在F盤新建一個(gè)Maven目錄(新建目錄的位置自定義)用來(lái)放置解壓后的文件夾，然后將apache-maven-3.2.3文件夾復(fù)制到F:\Maven下

配置Gradle環(huán)境變量，在系統(tǒng)環(huán)境變量中新建環(huán)境變量MAVEN_HOME，變量值為F:\Maven\apache-maven-3.2.3(Maven的根目錄)

然后點(diǎn)擊確定，在系統(tǒng)環(huán)境變量Path中追加%MAVEN_HOME%\bin;指向Maven的bin目錄

CMD運(yùn)行mvn -version，如出現(xiàn)以下截圖中的內(nèi)容說(shuō)明安裝成功

2.配置Maven

打開Eclipse，選擇Window -> Preferences，然后展開Maven選擇Installations，點(diǎn)擊Add

點(diǎn)擊Directory，在彈出的對(duì)話框中選擇Maven的安裝目錄，然后點(diǎn)擊Finish

然后勾選新添加的maven選項(xiàng)，點(diǎn)擊OK

修改Maven配文件，這里使用安裝的Maven配置文件。選擇User Settings，點(diǎn)擊Browser

選擇Maven安裝目錄下conf目錄下的settings.xml文件，然后點(diǎn)擊Update Settings，點(diǎn)擊OK

3.開發(fā)Web應(yīng)用程序

在Eclipse中新建Maven Project。選擇New -> Maven Project，然后點(diǎn)擊Next

Group Id輸入com.test，Artifact Id輸入maven。Packaging選擇war，然后點(diǎn)擊Finish

此時(shí)新建的Maven Project已經(jīng)是Web項(xiàng)目無(wú)需轉(zhuǎn)換了。上圖顯示紅色的x，因?yàn)檫@是一個(gè)web項(xiàng)目缺少web.xml配置文件。我們從其它地方復(fù)制META-INF和WEB-INF兩目錄過來(lái)，也可以從web項(xiàng)目中復(fù)制。結(jié)構(gòu)如下

打開pom.xml配置文件。我們需要配置Kotlin插件和Kotlin標(biāo)準(zhǔn)庫(kù)。配置如下

<properties>
    <kotlin.version>1.1.2</kotlin.version>
</properties>
 
<dependencies>
    <dependency>
        <groupId>org.jetbrains.kotlin</groupId>
        <artifactId>kotlin-stdlib</artifactId>
        <version>${kotlin.version}</version>
    </dependency>
 </dependencies>
 
<build>
  <!-- 只編譯Kotlin時(shí)配置 -->
    <!-- <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
    <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory> -->
  
    <plugins>
    <!-- Kotlin編譯插件必須配置在Maven編譯插件之前 -->
        <plugin>
        <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-maven-plugin</artifactId>
            <version>${kotlin.version}</version>
            <executions>
                <execution>
                    <id>compile</id>
                    <goals> <goal>compile</goal> </goals>
                    <!-- Kotlin與Java代碼混編時(shí)指定資源目錄 -->
                    <configuration>
                        <sourceDirs>
                           <sourceDir>${project.basedir}/src/main/kotlin</sourceDir>
                           <sourceDir>${project.basedir}/src/main/java</sourceDir>
                        </sourceDirs>
                    </configuration>
                </execution>
                <execution>
                    <id>test-compile</id>
                    <goals> <goal>test-compile</goal> </goals>
                    <configuration>
                        <sourceDirs>
                            <sourceDir>${project.basedir}/src/test/kotlin</sourceDir>
                            <sourceDir>${project.basedir}/src/test/java</sourceDir>
                        </sourceDirs>
                    </configuration>
                </execution>
            </executions>
        </plugin>
        
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.5.1</version>
            <configuration>
                <source>1.7</source>
                <target>1.7</target>
            </configuration>
            <executions>
                <!-- 替換會(huì)被 maven 特別處理的 default-compile -->
                <execution>
                    <id>default-compile</id>
                    <phase>none</phase>
                </execution>
                <!-- 替換會(huì)被 maven 特別處理的 default-testCompile -->
                <execution>
                    <id>default-testCompile</id>
                    <phase>none</phase>
                </execution>
                <execution>
                    <id>java-compile</id>
                    <phase>compile</phase>
                    <goals> <goal>compile</goal> </goals>
                </execution>
                <execution>
                    <id>java-test-compile</id>
                    <phase>test-compile</phase>
                    <goals> <goal>testCompile</goal> </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
  </build>

添加JavaEE類庫(kù)

<dependency>
    <groupId>javax</groupId>
    <artifactId>javaee-api</artifactId>
    <version>6.0</version>
    <scope>provided</scope>
</dependency>

添加war包插件

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-war-plugin</artifactId>  
    <version>2.6</version>  
    <configuration>  
        <warName>maven</warName>  
    </configuration>  
</plugin>

為了運(yùn)行web程序還需要tomcat插件

<plugin> 
    <groupId>org.apache.tomcat.maven</groupId> 
    <artifactId>tomcat7-maven-plugin</artifactId> 
    <version>2.2</version> 
    <configuration>
        <port>8080</port>
        <server>tomcat7</server>
        <path>/maven</path> <!-- 應(yīng)用的部署context path -->
    </configuration> 
</plugin>

保存后會(huì)自動(dòng)下載jar包依賴

選擇項(xiàng)目右擊，選擇Maven -> Update Project，點(diǎn)擊OK

然后在webapp下新建一個(gè)index.jsp，在index.jsp中輸入index

新建一個(gè)sourse目錄為src/main/kotlin用來(lái)存放Kotlin源代碼。點(diǎn)擊Finish

選擇Kotin視圖可快速新建Kotlin Class

選中src/main/kotlin，選擇New -> Kotlin Class，新建一個(gè)HelloWorld.kt文件

在HelloWorld.kt中編寫如下代碼

package com.test.servlet
 
import javax.servlet.http.HttpServlet
import javax.servlet.http.HttpServletRequest
import javax.servlet.http.HttpServletResponse
import javax.servlet.annotation.WebServlet
 
@WebServlet("/helloworld")
class HelloWorld : HttpServlet(){
override fun doGet(req: HttpServletRequest, resp: HttpServletResponse) {
        println("enter the doGet method");
        resp.writer.write("Hello, World")
    }
}

4.運(yùn)行應(yīng)用程序

在JavaEE視圖中右擊項(xiàng)目選擇Run as -> Run Configurations -> Maven Build，如果是第一次運(yùn)行會(huì)彈出如下對(duì)話框

在Goals一欄輸入tomcat7:run，然后點(diǎn)擊Run，運(yùn)行內(nèi)嵌的tomcat

控制臺(tái)最后輸出如下截圖內(nèi)容則說(shuō)明啟動(dòng)成功

在瀏覽器地址欄輸入http://localhost:8080/maven

輸入Servlet的訪問路徑http://localhost:8080/maven/helloworld