1 /* 2 * Copyright (C) 2017 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 androidx.room.solver.binderprovider 18 19 import androidx.room.ext.PagingTypeNames 20 import androidx.room.parser.ParsedQuery 21 import androidx.room.processor.Context 22 import androidx.room.processor.ProcessorErrors 23 import androidx.room.solver.QueryResultBinderProvider 24 import androidx.room.solver.query.result.ListQueryResultAdapter 25 import androidx.room.solver.query.result.PositionalDataSourceQueryResultBinder 26 import androidx.room.solver.query.result.QueryResultBinder 27 import javax.lang.model.type.DeclaredType 28 import javax.lang.model.type.TypeMirror 29 30 class DataSourceQueryResultBinderProvider(val context: Context) : QueryResultBinderProvider { 31 private val dataSourceTypeMirror: TypeMirror? by lazy { 32 context.processingEnv.elementUtils 33 .getTypeElement(PagingTypeNames.DATA_SOURCE.toString())?.asType() 34 } 35 36 private val positionalDataSourceTypeMirror: TypeMirror? by lazy { 37 context.processingEnv.elementUtils 38 .getTypeElement(PagingTypeNames.POSITIONAL_DATA_SOURCE.toString())?.asType() 39 } 40 41 override fun provide(declared: DeclaredType, query: ParsedQuery): QueryResultBinder { 42 if (query.tables.isEmpty()) { 43 context.logger.e(ProcessorErrors.OBSERVABLE_QUERY_NOTHING_TO_OBSERVE) 44 } 45 val typeArg = declared.typeArguments.last() 46 val listAdapter = context.typeAdapterStore.findRowAdapter(typeArg, query)?.let { 47 ListQueryResultAdapter(it) 48 } 49 val tableNames = ((listAdapter?.accessedTableNames() ?: emptyList()) 50 + query.tables.map { it.name }).toSet() 51 return PositionalDataSourceQueryResultBinder(listAdapter, tableNames) 52 } 53 54 override fun matches(declared: DeclaredType): Boolean { 55 if (dataSourceTypeMirror == null || positionalDataSourceTypeMirror == null) { 56 return false 57 } 58 if (declared.typeArguments.isEmpty()) { 59 return false 60 } 61 val erasure = context.processingEnv.typeUtils.erasure(declared) 62 val isDataSource = context.processingEnv.typeUtils 63 .isAssignable(erasure, dataSourceTypeMirror) 64 if (!isDataSource) { 65 return false 66 } 67 val isPositional = context.processingEnv.typeUtils 68 .isAssignable(erasure, positionalDataSourceTypeMirror) 69 if (!isPositional) { 70 context.logger.e(ProcessorErrors.PAGING_SPECIFY_DATA_SOURCE_TYPE) 71 } 72 return true 73 } 74 } 75
