1 /* <lambda>null2 * Copyright (C) 2018 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 import com.android.tools.metalava.model.item.DefaultTypeParameterItem 20 import com.android.tools.metalava.model.type.TypeItemFactory 21 22 /** 23 * Represents a type parameter list. For example, in class<S, T extends List<String>> the type 24 * parameter list is <S, T extends List<String>> and has type parameters named S and T, and type 25 * parameter T has bounds List<String>. 26 */ 27 interface TypeParameterList : List<TypeParameterItem> { 28 /** 29 * Returns source representation of this type parameter, using fully qualified names (possibly 30 * with java.lang. removed if requested via options) 31 */ 32 override fun toString(): String 33 34 /** Implemented according to the general [java.util.List.equals] contract. */ 35 override fun equals(other: Any?): Boolean 36 37 /** Implemented according to the general [java.util.List.hashCode] contract. */ 38 override fun hashCode(): Int 39 40 companion object { 41 private val emptyListDelegate = emptyList<TypeParameterItem>() 42 43 /** Type parameter list when there are no type parameters */ 44 val NONE: TypeParameterList = 45 object : TypeParameterList, List<TypeParameterItem> by emptyListDelegate { 46 override fun toString(): String = "" 47 48 override fun equals(other: Any?) = emptyListDelegate == other 49 50 override fun hashCode() = emptyListDelegate.hashCode() 51 } 52 } 53 } 54 55 class DefaultTypeParameterList 56 private constructor(private val typeParameters: List<TypeParameterItem>) : 57 TypeParameterList, List<TypeParameterItem> by typeParameters { 58 <lambda>null59 private val toString by lazy { 60 buildString { 61 if (this@DefaultTypeParameterList.isNotEmpty()) { 62 append("<") 63 var first = true 64 for (param in this@DefaultTypeParameterList) { 65 if (!first) { 66 append(", ") 67 } 68 first = false 69 append(param.toSource()) 70 } 71 append(">") 72 } 73 } 74 } 75 toStringnull76 override fun toString(): String { 77 return toString 78 } 79 equalsnull80 override fun equals(other: Any?) = typeParameters == other 81 82 override fun hashCode() = typeParameters.hashCode() 83 84 companion object { 85 86 /** 87 * Create a list of [TypeParameterItem] and a corresponding [TypeItemFactory] from model 88 * specific parameter and bounds information. 89 * 90 * A type parameter list can contain cycles between its type parameters, e.g. 91 * 92 * class Node<L extends Node<L, R>, R extends Node<L, R>> 93 * 94 * Parsing that requires a multi-stage approach. 95 * 1. Separate the list into a mapping from `TypeParameterItem` that have not yet had their 96 * `bounds` property initialized to the model specific parameter. 97 * 2. Create a nested factory of the enclosing factory which includes the type parameters. 98 * That will allow references between them to be resolved. 99 * 3. Complete the initialization by converting each bounds string into a TypeItem. 100 * 101 * @param containingTypeItemFactory the containing factory. 102 * @param scopeDescription the description of the scope that will be created by the factory. 103 * @param inputParams a list of the model specific type parameters. 104 * @param paramFactory a function that will create a [TypeParameterItem] from the model 105 * specified parameter [P]. 106 * @param boundsGetter a function that will create a list of [BoundsTypeItem] from the model 107 * specific bounds which will be stored in [DefaultTypeParameterItem.bounds]. 108 * @param P the type of the underlying model specific type parameter objects. 109 * @param F the type of the model specific [TypeItemFactory]. 110 */ 111 fun <P, F : TypeItemFactory<*, F>> createTypeParameterItemsAndFactory( 112 containingTypeItemFactory: F, 113 scopeDescription: String, 114 inputParams: List<P>, 115 paramFactory: (P) -> DefaultTypeParameterItem, 116 boundsGetter: (F, P) -> List<BoundsTypeItem>, 117 ): TypeParameterListAndFactory<F> { 118 // First, create a Map from [TypeParameterItem] to the model specific parameter. Using 119 // the [paramFactory] to convert the model specific parameter to a [TypeParameterItem]. 120 val typeParameterItemToBounds = inputParams.associateBy { param -> paramFactory(param) } 121 122 // Then, create a [TypeItemFactory] for this list of type parameters. 123 val typeParameters = typeParameterItemToBounds.keys.toList() 124 val typeItemFactory = 125 containingTypeItemFactory.nestedFactory(scopeDescription, typeParameters) 126 127 // Then, create and set the bounds in the [TypeParameterItem] passing in the 128 // [TypeItemFactory] to allow cross-references to type parameters to be resolved. 129 for ((typeParameter, param) in typeParameterItemToBounds) { 130 val boundsTypeItems = boundsGetter(typeItemFactory, param) 131 typeParameter.bounds = boundsTypeItems 132 } 133 134 // Pair the list up with the [TypeItemFactory] so that the latter can be reused. 135 val typeParameterList = DefaultTypeParameterList(typeParameters) 136 return TypeParameterListAndFactory(typeParameterList, typeItemFactory) 137 } 138 } 139 } 140 141 /** 142 * Group up [typeParameterList] and the [factory] that was used to resolve references when creating 143 * their [BoundsTypeItem]s. 144 */ 145 data class TypeParameterListAndFactory<F : TypeItemFactory<*, F>>( 146 val typeParameterList: TypeParameterList, 147 val factory: F, 148 ) 149