Kapt:如何阅读注释(及其参数)

Question

拥有一个类：

@MarkerForKapt
@AnotherAnnotation(withParameter = "X")
class MyClass

还有一个处理器：

class MyProcessor : AbstractProcessor() {
override fun getSupportedAnnotationTypes() = setOf(MarkerForKapt::class.qualifiedName)
override fun process(annotations: Set<TypeElement>, roundEnv: RoundEnvironment): Boolean {

val element = roundEnv.getElementsAnnotatedWith(MarkerForKapt::class.java).single()

}
}

如何从@AnotherAnnotation读取值"X"？

Answer 1

将rt.jar添加到配置：

build.gradle.kts:

implementation(files("${System.getProperty("java.home")}/../lib/tools.jar"))

处理器：

import com.sun.tools.javac.code.Symbol

override fun process(annotations: Set<TypeElement>, roundEnv: RoundEnvironment): Boolean {

val element = roundEnv.getElementsAnnotatedWith(MarkerForKapt::class.java).single()

element as Symbol.ClassSymbol
val annotation: AnotherAnnotation? = element.getAnnotation(AnotherAnnotation::class.java)
val theX = annotation?.withParameter
}