1 /* 2 * Copyright (C) 2017 The Dagger Authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package dagger.internal.codegen.writing; 18 19 import com.squareup.javapoet.ClassName; 20 import com.squareup.javapoet.CodeBlock; 21 import dagger.internal.codegen.binding.ComponentDescriptor.ComponentMethodDescriptor; 22 import dagger.internal.codegen.javapoet.Expression; 23 24 /** A factory of code expressions used to access a single request for a binding in a component. */ 25 // TODO(bcorso): Rename this to RequestExpression? 26 abstract class BindingExpression { 27 28 /** 29 * Returns an expression that evaluates to the value of a request based on the given requesting 30 * class. 31 * 32 * @param requestingClass the class that will contain the expression 33 */ getDependencyExpression(ClassName requestingClass)34 abstract Expression getDependencyExpression(ClassName requestingClass); 35 36 /** 37 * Equivalent to {@link #getDependencyExpression} that is used only when the request is for an 38 * implementation of a component method. By default, just delegates to {@link 39 * #getDependencyExpression}. 40 */ getDependencyExpressionForComponentMethod( ComponentMethodDescriptor componentMethod, ComponentImplementation component)41 Expression getDependencyExpressionForComponentMethod( 42 ComponentMethodDescriptor componentMethod, ComponentImplementation component) { 43 return getDependencyExpression(component.name()); 44 } 45 46 /** Returns {@code true} if this binding expression should be encapsulated in a method. */ requiresMethodEncapsulation()47 boolean requiresMethodEncapsulation() { 48 return false; 49 } 50 51 /** 52 * Returns an expression for the implementation of a component method with the given request. 53 * 54 * @param component the component that will contain the implemented method 55 */ getComponentMethodImplementation( ComponentMethodDescriptor componentMethod, ComponentImplementation component)56 CodeBlock getComponentMethodImplementation( 57 ComponentMethodDescriptor componentMethod, ComponentImplementation component) { 58 // By default, just delegate to #getDependencyExpression(). 59 return CodeBlock.of( 60 "return $L;", 61 getDependencyExpressionForComponentMethod(componentMethod, component).codeBlock()); 62 } 63 } 64