Question

我有使用Java库的Scala控制台应用程序。我是Gradle和Scala的新手。我没有使用任何IDE，只有VS Code和Gradle。我可以使用Gradle构建应用程序，但是尝试运行时出现异常，未找到类。

$ gradle run
Exception in thread "main" java.lang.NoClassDefFoundError: scala/Product$class
        at scopt.Head$.<init>(options.scala:148)
        at scopt.Head$.<clinit>(options.scala)
        at scopt.OptionParser.head(options.scala:251)
        at console.App$$anon$1.<init>(App.scala:20)
        at console.App$.main(App.scala:19)
        at console.App.main(App.scala)
Caused by: java.lang.ClassNotFoundException: scala.Product$class
        at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
        at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
        ... 6 more

我猜测jar文件不会复制到build / distribution或build / libs文件夹中。

构建文件如下：

    plugins {
    // Apply the scala plugin to add support for Scala
    id 'scala'
    id 'application'
    id 'distribution'
}

repositories {
    // Use jcenter for resolving your dependencies.
    // You can declare any Maven/Ivy/file repository here.
    jcenter()
    maven {
            url 'https://plugins.gradle.org/m2/'
    }
}

dependencies {
    implementation 'org.scala-lang:scala-library:2.12.7'
    implementation 'org.mongodb.scala:mongo-scala-bson_2.12:2.5.0'
    implementation 'org.apache.poi:poi:4.0.1'
    implementation 'org.apache.logging.log4j:log4j-core:2.11.1'
    implementation 'org.apache.logging.log4j:log4j-api:2.11.1'
    implementation 'org.slf4j:slf4j-nop:1.7.25'
    implementation 'org.apache.poi:poi-ooxml:4.0.1'
    implementation group: 'com.github.scopt', name: 'scopt_2.11', version: '3.7.1'
    implementation group: 'com.google.guava', name: 'guava', version: '27.0.1-jre'
    implementation group: 'org.apache.logging.log4j', name: 'log4j-api-scala_2.12', version: '11.0'
    implementation 'com.github.pcj:google-options:1.0.0'

    // Use Scalatest for testing our library
    testImplementation 'junit:junit:4.12'
    testImplementation 'org.scalatest:scalatest_2.12:3.0.5'

    // Need scala-xml at test runtime
    testRuntimeOnly 'org.scala-lang.modules:scala-xml_2.12:1.1.1'
}
group = 'matches'
version = '1.0'
description = 'matches'
sourceCompatibility = '11'
mainClassName = 'console.App'

application {
    mainClassName = "console.App"
}

我不确定需要添加什么内容。

Answer 1

您正在混合库scala 2.11和scala 2.12。更改为实现组：“ com.github.scopt”，名称：“ scopt_2.12”，版本：“ 3.7.1”

具有Java库的Scala Gradle控制台应用程序

1 个答案: