WorkerGenerator.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.hilt.work
import androidx.hilt.ClassNames
import androidx.hilt.ext.S
import androidx.hilt.ext.T
import androidx.hilt.ext.addGeneratedAnnotation
import androidx.room.compiler.processing.XProcessingEnv
import androidx.room.compiler.processing.addOriginatingElement
import androidx.room.compiler.processing.writeTo
import com.squareup.javapoet.AnnotationSpec
import com.squareup.javapoet.JavaFile
import com.squareup.javapoet.MethodSpec
import com.squareup.javapoet.ParameterizedTypeName
import com.squareup.javapoet.TypeSpec
import com.squareup.javapoet.WildcardTypeName
import javax.lang.model.element.Modifier
/**
* Source generator to support Hilt injection of Workers.
*
* Should generate:
* ```
* @Module
* @InstallIn(SingletonComponent.class)
* public interface $_HiltModule {
* @Binds
* @IntoMap
* @StringKey("pkg.$")
* ViewModelAssistedFactory<? extends Worker> bind($_AssistedFactory factory)
* }
* ```
* and
* ```
* @AssistedFactory
* public interface $_AssistedFactory extends WorkerAssistedFactory<$> {
*
* }
* ```
*/
internal class WorkerGenerator(
private val processingEnv: XProcessingEnv,
private val injectedWorker: WorkerElement
) {
fun generate() {
val assistedFactoryTypeSpec = TypeSpec.interfaceBuilder(injectedWorker.factoryClassName)
.addOriginatingElement(injectedWorker.typeElement)
.addGeneratedAnnotation(processingEnv)
.addAnnotation(ClassNames.ASSISTED_FACTORY)
.addModifiers(Modifier.PUBLIC)
.addSuperinterface(injectedWorker.factorySuperTypeName)
.build()
JavaFile.builder(injectedWorker.factoryClassName.packageName(), assistedFactoryTypeSpec)
.build()
.writeTo(processingEnv.filer)
val hiltModuleTypeSpec = TypeSpec.interfaceBuilder(injectedWorker.moduleClassName)
.addOriginatingElement(injectedWorker.typeElement)
.addGeneratedAnnotation(processingEnv)
.addAnnotation(ClassNames.MODULE)
.addAnnotation(
AnnotationSpec.builder(ClassNames.INSTALL_IN)
.addMember("value", "$T.class", ClassNames.SINGLETON_COMPONENT)
.build()
)
.addAnnotation(
AnnotationSpec.builder(ClassNames.ORIGINATING_ELEMENT)
.addMember(
"topLevelClass",
"$T.class",
injectedWorker.className.topLevelClassName()
)
.build()
)
.addModifiers(Modifier.PUBLIC)
.addMethod(
MethodSpec.methodBuilder("bind")
.addAnnotation(ClassNames.BINDS)
.addAnnotation(ClassNames.INTO_MAP)
.addAnnotation(
AnnotationSpec.builder(ClassNames.STRING_KEY)
.addMember("value", S, injectedWorker.className.reflectionName())
.build()
)
.addModifiers(Modifier.ABSTRACT, Modifier.PUBLIC)
.returns(
ParameterizedTypeName.get(
ClassNames.WORKER_ASSISTED_FACTORY,
WildcardTypeName.subtypeOf(ClassNames.LISTENABLE_WORKER)
)
)
.addParameter(injectedWorker.factoryClassName, "factory")
.build()
)
.build()
JavaFile.builder(injectedWorker.moduleClassName.packageName(), hiltModuleTypeSpec)
.build()
.writeTo(processingEnv.filer)
}
}