dagger.internal.codegen.MultibindingExpression.java Source code

Introduction

Here is the source code for dagger.internal.codegen.MultibindingExpression.java

Source

/*
 * Copyright (C) 2018 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.internal.codegen;

import static dagger.internal.codegen.BindingRequest.bindingRequest;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.google.common.collect.Sets.SetView;
import com.squareup.javapoet.ClassName;
import com.squareup.javapoet.CodeBlock;
import dagger.internal.codegen.ModifiableBindingMethods.ModifiableBindingMethod;
import dagger.model.DependencyRequest;
import dagger.model.RequestKind;
import java.util.Optional;

/** An abstract base class for multibinding {@link BindingExpression}s. */
abstract class MultibindingExpression extends SimpleInvocationBindingExpression {
    private final ProvisionBinding binding;
    private final ComponentImplementation componentImplementation;

    MultibindingExpression(ResolvedBindings resolvedBindings, ComponentImplementation componentImplementation) {
        super(resolvedBindings);
        this.componentImplementation = componentImplementation;
        this.binding = (ProvisionBinding) resolvedBindings.contributionBinding();
    }

    @Override
    Expression getDependencyExpression(ClassName requestingClass) {
        Expression expression = buildDependencyExpression(requestingClass);
        componentImplementation.registerImplementedMultibinding(binding, bindingRequest());
        return expression;
    }

    /**
     * Returns an expression that evaluates to the value of a multibinding request for the given
     * requesting class.
     */
    protected abstract Expression buildDependencyExpression(ClassName requestingClass);

    /**
     * Returns the subset of {@code dependencies} that represent multibinding contributions that were
     * not included in a superclass implementation of this multibinding method. This is relevant only
     * for ahead-of-time subcomponents. When not generating ahead-of-time subcomponents there is only
     * one implementation of a multibinding expression and all {@link DependencyRequest}s from the
     * argment are returned.
     */
    protected SetView<DependencyRequest> getNewContributions(ImmutableSet<DependencyRequest> dependencies) {
        return Sets.difference(dependencies, superclassContributions());
    }

    /**
     * Returns the {@link CodeBlock} representing a call to a superclass implementation of the
     * modifiable binding method that encapsulates this binding, if it exists. This is only possible
     * when generating ahead-of-time subcomponents.
     */
    protected Optional<CodeBlock> superMethodCall() {
        if (componentImplementation.superclassImplementation().isPresent()) {
            Optional<ModifiableBindingMethod> method = componentImplementation
                    .getModifiableBindingMethod(bindingRequest());
            if (method.isPresent()) {
                if (!superclassContributions().isEmpty()) {
                    return Optional.of(CodeBlock.of("super.$L()", method.get().methodSpec().name));
                }
            }
        }
        return Optional.empty();
    }

    private BindingRequest bindingRequest() {
        return BindingRequest.bindingRequest(binding.key(), RequestKind.INSTANCE);
    }

    private ImmutableSet<DependencyRequest> superclassContributions() {
        return componentImplementation.superclassContributionsMade(bindingRequest());
    }
}