KspFiler.kt
/*
* Copyright 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.ksp
import androidx.room.compiler.processing.XFiler
import androidx.room.compiler.processing.XMessager
import androidx.room.compiler.processing.util.ISSUE_TRACKER_LINK
import com.google.devtools.ksp.processing.CodeGenerator
import com.google.devtools.ksp.processing.Dependencies
import com.google.devtools.ksp.symbol.KSClassDeclaration
import com.google.devtools.ksp.symbol.KSFile
import com.squareup.javapoet.JavaFile
import com.squareup.kotlinpoet.FileSpec
import com.squareup.kotlinpoet.OriginatingElementsHolder
import java.io.OutputStream
import javax.lang.model.element.Element
import javax.tools.Diagnostic
internal class KspFiler(
private val delegate: CodeGenerator,
private val messager: XMessager,
) : XFiler {
override fun write(javaFile: JavaFile, mode: XFiler.Mode) {
val originatingElements = javaFile.typeSpec.originatingElements
.toOriginatingElements()
createNewFile(
originatingElements = originatingElements,
packageName = javaFile.packageName,
fileName = javaFile.typeSpec.name,
extensionName = "java",
aggregating = mode == XFiler.Mode.Aggregating
).use { outputStream ->
outputStream.bufferedWriter(Charsets.UTF_8).use {
javaFile.writeTo(it)
}
}
}
override fun write(fileSpec: FileSpec, mode: XFiler.Mode) {
val originatingElements = fileSpec.members
.filterIsInstance<OriginatingElementsHolder>()
.flatMap { it.originatingElements }
.toOriginatingElements()
createNewFile(
originatingElements = originatingElements,
packageName = fileSpec.packageName,
fileName = fileSpec.name,
extensionName = "kt",
aggregating = mode == XFiler.Mode.Aggregating
).use { outputStream ->
outputStream.bufferedWriter(Charsets.UTF_8).use {
fileSpec.writeTo(it)
}
}
}
private fun createNewFile(
originatingElements: OriginatingElements,
packageName: String,
fileName: String,
extensionName: String,
aggregating: Boolean
): OutputStream {
val dependencies = if (originatingElements.isEmpty()) {
messager.printMessage(
Diagnostic.Kind.WARNING,
"""
No dependencies are reported for $fileName which will prevent
incremental compilation.
Please file a bug at $ISSUE_TRACKER_LINK.
""".trimIndent()
)
Dependencies.ALL_FILES
} else {
Dependencies(
aggregating = aggregating,
sources = originatingElements.files.distinct().toTypedArray()
)
}
if (originatingElements.classes.isNotEmpty()) {
delegate.associateWithClasses(
classes = originatingElements.classes,
packageName = packageName,
fileName = fileName,
extensionName = extensionName
)
}
return delegate.createNewFile(
dependencies = dependencies,
packageName = packageName,
fileName = fileName,
extensionName = extensionName
)
}
private data class OriginatingElements(
val files: List<KSFile>,
val classes: List<KSClassDeclaration>,
) {
fun isEmpty(): Boolean = files.isEmpty() && classes.isEmpty()
}
private fun List<Element>.toOriginatingElements(): OriginatingElements {
val files = mutableListOf<KSFile>()
val classes = mutableListOf<KSClassDeclaration>()
forEach { element ->
when (element) {
is KSFileAsOriginatingElement -> files.add(element.ksFile)
is KSClassDeclarationAsOriginatingElement -> classes.add(element.ksClassDeclaration)
else -> error("Unexpected element type in originating elements. $element")
}
}
return OriginatingElements(files, classes)
}
}