JavacProcessingEnvMessager.kt
/*
* Copyright (C) 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.room.compiler.processing.javac
import androidx.room.compiler.processing.XAnnotation
import androidx.room.compiler.processing.XAnnotationValue
import androidx.room.compiler.processing.XElement
import androidx.room.compiler.processing.XMessager
import javax.annotation.processing.Messager
import javax.lang.model.element.Element
import javax.tools.Diagnostic
internal class JavacProcessingEnvMessager(
val delegate: Messager
) : XMessager() {
override fun onPrintMessage(
kind: Diagnostic.Kind,
msg: String,
element: XElement?,
annotation: XAnnotation?,
annotationValue: XAnnotationValue?
) {
if (element == null) {
delegate.printMessage(kind, msg)
return
}
val javacElement = (element as JavacElement).element
@Suppress("NAME_SHADOWING") // intentional to avoid reporting without location
val msg = if (javacElement.isFromCompiledClass()) {
"$msg - ${element.fallbackLocationText}"
} else {
msg
}
if (annotation == null) {
delegate.printMessage(kind, msg, javacElement)
return
}
val javacAnnotation = (annotation as JavacAnnotation).mirror
if (annotationValue == null) {
delegate.printMessage(kind, msg, javacElement, javacAnnotation)
return
}
val javacAnnotationValue = (annotationValue as JavacAnnotationValue).annotationValue
delegate.printMessage(
kind, msg, javacElement, javacAnnotation, javacAnnotationValue
)
}
companion object {
/**
* Indicates whether an element comes from a compiled class.
*
* If this method fails to identify if the element comes from a compiled class it will
* default to returning false. Note that this is a poor-man's method of identifying if
* the java source of the element is available without depending on compiler tools.
*/
private fun Element.isFromCompiledClass(): Boolean {
fun getClassFileString(symbol: Any): String =
try {
symbol.javaClass.getDeclaredField("classfile").get(symbol).toString()
} catch (ex: NoSuchFieldException) {
getClassFileString(
symbol.javaClass.superclass.getDeclaredField("owner").get(symbol)
)
}
return try {
getClassFileString(this).let {
it.contains(".jar") || it.contains(".class")
}
} catch (ex: Throwable) {
false
}
}
}
}