1 /* 2 * Copyright (C) 2016 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.binding; 18 19 import static androidx.room.compiler.processing.XTypeKt.isArray; 20 import static dagger.internal.codegen.binding.SourceFiles.classFileName; 21 import static dagger.internal.codegen.extension.DaggerStreams.toImmutableList; 22 import static dagger.internal.codegen.javapoet.CodeBlocks.makeParametersCodeBlock; 23 import static dagger.internal.codegen.javapoet.CodeBlocks.toParametersCodeBlock; 24 import static dagger.internal.codegen.xprocessing.XAnnotationValues.characterLiteralWithSingleQuotes; 25 import static dagger.internal.codegen.xprocessing.XElements.getSimpleName; 26 import static dagger.internal.codegen.xprocessing.XTypes.asArray; 27 import static dagger.internal.codegen.xprocessing.XTypes.isTypeOf; 28 29 import androidx.room.compiler.processing.XAnnotation; 30 import androidx.room.compiler.processing.XAnnotationValue; 31 import androidx.room.compiler.processing.XType; 32 import androidx.room.compiler.processing.XTypeElement; 33 import com.squareup.javapoet.ClassName; 34 import com.squareup.javapoet.CodeBlock; 35 import dagger.internal.codegen.javapoet.TypeNames; 36 37 /** 38 * Returns an expression creating an instance of the visited annotation type. Its parameter must be 39 * a class as generated by {@link dagger.internal.codegen.writing.AnnotationCreatorGenerator}. 40 * 41 * <p>Note that {@code AnnotationValue#toString()} is the source-code representation of the value 42 * <em>when used in an annotation</em>, which is not always the same as the representation needed 43 * when creating the value in a method body. 44 * 45 * <p>For example, inside an annotation, a nested array of {@code int}s is simply {@code {1, 2, 3}}, 46 * but in code it would have to be {@code new int[] {1, 2, 3}}. 47 */ 48 public final class AnnotationExpression { 49 private final XAnnotation annotation; 50 private final ClassName creatorClass; 51 AnnotationExpression(XAnnotation annotation)52 AnnotationExpression(XAnnotation annotation) { 53 this.annotation = annotation; 54 this.creatorClass = getAnnotationCreatorClassName(annotation.getType().getTypeElement()); 55 } 56 57 /** 58 * Returns an expression that calls static methods on the annotation's creator class to create an 59 * annotation instance equivalent the annotation passed to the constructor. 60 */ getAnnotationInstanceExpression()61 CodeBlock getAnnotationInstanceExpression() { 62 return getAnnotationInstanceExpression(annotation); 63 } 64 getAnnotationInstanceExpression(XAnnotation annotation)65 private CodeBlock getAnnotationInstanceExpression(XAnnotation annotation) { 66 return CodeBlock.of( 67 "$T.$L($L)", 68 creatorClass, 69 createMethodName(annotation.getType().getTypeElement()), 70 makeParametersCodeBlock( 71 annotation.getAnnotationValues().stream() 72 .map(this::getValueExpression) 73 .collect(toImmutableList()))); 74 } 75 76 /** 77 * Returns the name of the generated class that contains the static {@code create} methods for an 78 * annotation type. 79 */ getAnnotationCreatorClassName(XTypeElement annotationType)80 public static ClassName getAnnotationCreatorClassName(XTypeElement annotationType) { 81 ClassName annotationTypeName = annotationType.getClassName(); 82 return annotationTypeName 83 .topLevelClassName() 84 .peerClass(classFileName(annotationTypeName) + "Creator"); 85 } 86 createMethodName(XTypeElement annotationType)87 public static String createMethodName(XTypeElement annotationType) { 88 return "create" + getSimpleName(annotationType); 89 } 90 91 /** 92 * Returns an expression that evaluates to a {@code value} of a given type on an {@code 93 * annotation}. 94 */ getValueExpression(XAnnotationValue value)95 CodeBlock getValueExpression(XAnnotationValue value) { 96 if (isArray(value.getValueType())) { 97 XType componentType = asArray(value.getValueType()).getComponentType(); 98 return CodeBlock.of( 99 "new $T[] {$L}", 100 // TODO(b/264464791): The KClass -> Class swap can be removed once this bug is fixed. 101 isTypeOf(componentType, TypeNames.KCLASS) 102 ? TypeNames.CLASS 103 : componentType.getRawType().getTypeName(), 104 value.asAnnotationValueList().stream() 105 .map(this::getValueExpression) 106 .collect(toParametersCodeBlock())); 107 } else if (value.hasEnumValue()) { 108 return CodeBlock.of( 109 "$T.$L", 110 value.asEnum().getEnclosingElement().getClassName(), 111 getSimpleName(value.asEnum())); 112 } else if (value.hasAnnotationValue()) { 113 return getAnnotationInstanceExpression(value.asAnnotation()); 114 } else if (value.hasTypeValue()) { 115 return CodeBlock.of("$T.class", value.asType().getTypeElement().getClassName()); 116 } else if (value.hasStringValue()) { 117 return CodeBlock.of("$S", value.asString()); 118 } else if (value.hasByteValue()) { 119 return CodeBlock.of("(byte) $L", value.asByte()); 120 } else if (value.hasCharValue()) { 121 // TODO(bcorso): Replace when https://github.com/square/javapoet/issues/698 is fixed. 122 return CodeBlock.of("$L", characterLiteralWithSingleQuotes(value.asChar())); 123 } else if (value.hasDoubleValue()) { 124 return CodeBlock.of("$LD", value.asDouble()); 125 } else if (value.hasFloatValue()) { 126 return CodeBlock.of("$LF", value.asFloat()); 127 } else if (value.hasLongValue()) { 128 return CodeBlock.of("$LL", value.asLong()); 129 } else if (value.hasShortValue()) { 130 return CodeBlock.of("(short) $L", value.asShort()); 131 } else { 132 return CodeBlock.of("$L", value.getValue()); 133 } 134 } 135 } 136