AnnotationMirrorExt.kt
/*
* Copyright 2023 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 com.google.auto.common.MoreElements
import com.google.auto.common.MoreTypes
import java.lang.annotation.Repeatable
import javax.lang.model.element.AnnotationMirror
import javax.lang.model.type.TypeKind
import javax.lang.model.util.ElementFilter
/** Returns true if the given [AnnotationMirror] represents a repeatable annotation. */
internal fun AnnotationMirror.isRepeatable(): Boolean {
try {
val valueType =
ElementFilter.methodsIn(MoreTypes.asTypeElement(annotationType).enclosedElements)
.singleOrNull { it.simpleName.toString() == "value" }
?.returnType
// The contract of a repeatable annotation requires that the container annotation have a
// single "default" method that returns an array typed with the repeatable annotation type.
if (valueType == null || valueType.kind != TypeKind.ARRAY) {
return false
}
val componentType = MoreTypes.asArray(valueType).componentType
if (componentType.kind != TypeKind.DECLARED) {
return false
}
val componentElement = MoreTypes.asDeclared(componentType).asElement()
// Ideally we would read the value of the Repeatable annotation to get the container class
// type and check that it matches "this" type. However, there seems to be a KSP bug where
// the value of Repeatable is not present so the best we can do is check that all the nested
// members are annotated with repeatable.
// https://github.com/google/ksp/issues/358
return MoreElements.isAnnotationPresent(componentElement, Repeatable::class.java) ||
// The java and kotlin versions of Repeatable are not interchangeable.
// https://github.com/google/ksp/issues/459 asks whether the built in type
// mapper should convert them, but it may not be possible because there are
// differences to how they work (eg different parameters).
MoreElements.isAnnotationPresent(
componentElement, kotlin.annotation.Repeatable::class.java
)
} catch (t: Throwable) {
// TODO(b/314160063): Turbine can throw when getting enclosed elements. Remove this once
// we have a better way to work around Turbine exception.
return false
}
}