java.lang.VerifyError用kotlin创建一个gradle任务

Question

我尝试用kotlin写一个gradle任务,这是我的代码:

GreetingTask.kt

class GreetingTask : DefaultTask() {
    @TaskAction
    fun greet() {
        println("greet!")
    }
}

的build.gradle

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:0.12.613"
    }
}

apply plugin: "kotlin"

dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:0.12.613"
    compile gradleApi()
}

GreetingTaskTest

class GreetingTaskTest {

    @Test
    public fun canAddTaskToProject() {
        val project = ProjectBuilder.builder().build()
        val task = project.task(hashMapOf("type" to javaClass<GreetingTask>()), "greeting")
        assertTrue(task is GreetingTask)
    }
}

现在运行测试时会产生以下结果:

java.lang.VerifyError at GreetingTaskTest.kt:20
// reason -> Cannot inherit from final class

这是哪一行:

val task = project.task(hashMapOf("type" to javaClass<GreetingTask>()), "greeting")

我想知道的是:

这个问题来自哪里,我该如何解决？

Answer 1

默认情况下,Kotlin中的类是最终的,与java中的open相比.

将类声明GreetingTask为"open",此错误消息消失.

open class GreetingTask : DefaultTask() { 
    ...
}