1 /* 2 * Copyright (C) 2023 The Android Open Source Project 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 com.android.tools.metalava.model 18 19 /** 20 * Modifiers for a [TypeItem], analogous to [ModifierList]s for [Item]s. Contains type-use 21 * annotation information. 22 */ 23 interface TypeModifiers { 24 /** The type-use annotations applied to the owning type. */ annotationsnull25 fun annotations(): List<AnnotationItem> 26 27 /** Adds the [annotation] to the list of annotations for the type. */ 28 fun addAnnotation(annotation: AnnotationItem) 29 30 /** Removes the [annotation] from the list of annotations for the type, if it was present. */ 31 fun removeAnnotation(annotation: AnnotationItem) 32 33 /** The nullability of the type. */ 34 fun nullability(): TypeNullability 35 36 /** 37 * Updates the nullability of the type to [newNullability]. Does not add or remove any nullness 38 * annotations, so those should be handled separately through [addAnnotation] and/or 39 * [removeAnnotation], if needed. 40 */ 41 fun setNullability(newNullability: TypeNullability) 42 43 /** Create a copy of this to which modifications can be made. */ 44 fun duplicate(withNullability: TypeNullability? = null): TypeModifiers 45 46 /** Whether the [nullability] is [TypeNullability.NULLABLE]. */ 47 val isNullable 48 get() = nullability() == TypeNullability.NULLABLE 49 50 /** Whether the [nullability] is [TypeNullability.NONNULL]. */ 51 val isNonNull 52 get() = nullability() == TypeNullability.NONNULL 53 54 /** Whether the [nullability] is [TypeNullability.PLATFORM]. */ 55 val isPlatformNullability 56 get() = nullability() == TypeNullability.PLATFORM 57 } 58 59 /** An enum representing the possible nullness values of a type. */ 60 enum class TypeNullability( 61 /** Kotlin nullability suffix. */ 62 val suffix: String, 63 ) { 64 /** 65 * Nullability for a type that is annotated non-null, is primitive, or defined as non-null in 66 * Kotlin. 67 */ 68 NONNULL(""), 69 /** Nullability for a type that is annotated nullable or defined as nullable in Kotlin. */ 70 NULLABLE("?"), 71 /** Nullability for a Java type without a specified nullability. */ 72 PLATFORM("!"), 73 /** 74 * The nullability for a type without defined nullness. Examples include: 75 * - A Kotlin type variable with inherited nullability. 76 * - Wildcard types (nullness is defined through the bounds of the wildcard). 77 */ 78 UNDEFINED(""); 79 80 companion object { 81 /** Given a nullness [annotation], returns the corresponding [TypeNullability]. */ 82 fun ofAnnotation(annotation: AnnotationItem): TypeNullability { 83 return if (isNullableAnnotation(annotation.qualifiedName.orEmpty())) { 84 NULLABLE 85 } else if (isNonNullAnnotation(annotation.qualifiedName.orEmpty())) { 86 NONNULL 87 } else { 88 throw IllegalStateException("Not a nullness annotation: $annotation") 89 } 90 } 91 } 92 } 93