java/dagger/hilt/android/processor/internal/androidentrypoint/ActivityGenerator.java

/*
 * Copyright (C) 2019 The Dagger Authors.
 *
 * 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 dagger.hilt.android.processor.internal.androidentrypoint;

import com.squareup.javapoet.ClassName;
import com.squareup.javapoet.JavaFile;
import com.squareup.javapoet.MethodSpec;
import com.squareup.javapoet.ParameterSpec;
import com.squareup.javapoet.TypeSpec;
import com.squareup.javapoet.TypeVariableName;
import dagger.hilt.android.processor.internal.AndroidClassNames;
import dagger.hilt.processor.internal.Processors;
import java.io.IOException;
import javax.annotation.processing.ProcessingEnvironment;
import javax.lang.model.element.Modifier;

/** Generates an Hilt Activity class for the @AndroidEntryPoint annotated class. */
public final class ActivityGenerator {

  private final ProcessingEnvironment env;
  private final AndroidEntryPointMetadata metadata;
  private final ClassName generatedClassName;

  public ActivityGenerator(ProcessingEnvironment env, AndroidEntryPointMetadata metadata) {
    this.env = env;
    this.metadata = metadata;

    generatedClassName = metadata.generatedClassName();
  }

  // @Generated("ActivityGenerator")
  // abstract class Hilt_$CLASS extends $BASE implements ComponentManager<?> {
  //   ...
  // }
  public void generate() throws IOException {
    TypeSpec.Builder builder =
        TypeSpec.classBuilder(generatedClassName.simpleName())
            .addOriginatingElement(metadata.element())
            .superclass(metadata.baseClassName())
            .addModifiers(metadata.generatedClassModifiers());

    Generators.addGeneratedBaseClassJavadoc(builder, AndroidClassNames.ANDROID_ENTRY_POINT);
    Processors.addGeneratedAnnotation(builder, env, getClass());

      Generators.copyConstructors(metadata.baseElement(), builder);
      builder.addMethod(onCreate());


    metadata.baseElement().getTypeParameters().stream()
        .map(TypeVariableName::get)
        .forEachOrdered(builder::addTypeVariable);

    Generators.addComponentOverride(metadata, builder);
    Generators.copyLintAnnotations(metadata.element(), builder);

    Generators.addInjectionMethods(metadata, builder);

    if (Processors.isAssignableFrom(metadata.baseElement(), AndroidClassNames.COMPONENT_ACTIVITY)
        && !metadata.overridesAndroidEntryPointClass()) {
      builder.addMethod(getDefaultViewModelProviderFactory());
    }

    JavaFile.builder(generatedClassName.packageName(), builder.build())
        .build()
        .writeTo(env.getFiler());
  }

  // @CallSuper
  // @Override
  // protected void onCreate(@Nullable Bundle savedInstanceState) {
  //   inject();
  //   super.onCreate(savedInstanceState);
  // }
  private MethodSpec onCreate() {
    return MethodSpec.methodBuilder("onCreate")
        .addAnnotation(AndroidClassNames.CALL_SUPER)
        .addAnnotation(Override.class)
        .addModifiers(Modifier.PROTECTED)
        .addParameter(
            ParameterSpec.builder(AndroidClassNames.BUNDLE, "savedInstanceState")
                .addAnnotation(AndroidClassNames.NULLABLE)
                .build())
        .addStatement("inject()")
        .addStatement("super.onCreate(savedInstanceState)")
        .build();
  }

  // @Override
  // public ViewModelProvider.Factory getDefaultViewModelProviderFactory() {
  //   return DefaultViewModelFactories.getActivityFactory(this);
  // }
  private MethodSpec getDefaultViewModelProviderFactory() {
    return MethodSpec.methodBuilder("getDefaultViewModelProviderFactory")
        .addAnnotation(Override.class)
        .addModifiers(Modifier.PUBLIC)
        .returns(AndroidClassNames.VIEW_MODEL_PROVIDER_FACTORY)
        .addStatement(
            "return $T.getActivityFactory(this)",
            AndroidClassNames.DEFAULT_VIEW_MODEL_FACTORIES)
        .build();
  }
}