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 17package android.arch.persistence.room.solver.binderprovider 18 19import android.arch.persistence.room.ext.PagingTypeNames 20import android.arch.persistence.room.parser.ParsedQuery 21import android.arch.persistence.room.processor.Context 22import android.arch.persistence.room.solver.QueryResultBinderProvider 23import android.arch.persistence.room.solver.query.result.TiledDataSourceQueryResultBinder 24import android.arch.persistence.room.solver.query.result.ListQueryResultAdapter 25import android.arch.persistence.room.solver.query.result.LivePagedListQueryResultBinder 26import android.arch.persistence.room.solver.query.result.QueryResultBinder 27import javax.lang.model.type.DeclaredType 28import javax.lang.model.type.TypeMirror 29 30class LivePagedListQueryResultBinderProvider(val context: Context) : QueryResultBinderProvider { 31 private val livePagedListTypeMirror: TypeMirror? by lazy { 32 context.processingEnv.elementUtils 33 .getTypeElement(PagingTypeNames.LIVE_PAGED_LIST_PROVIDER.toString())?.asType() 34 } 35 36 override fun provide(declared: DeclaredType, query: ParsedQuery): QueryResultBinder { 37 val typeArg = declared.typeArguments[1] 38 val listAdapter = context.typeAdapterStore.findRowAdapter(typeArg, query)?.let { 39 ListQueryResultAdapter(it) 40 } 41 val countedBinder = TiledDataSourceQueryResultBinder(listAdapter, 42 query.tables.map { it.name }) 43 return LivePagedListQueryResultBinder(countedBinder) 44 } 45 46 override fun matches(declared: DeclaredType): Boolean = 47 declared.typeArguments.size == 2 && isLivePagedList(declared) 48 49 private fun isLivePagedList(declared: DeclaredType): Boolean { 50 if (livePagedListTypeMirror == null) { 51 return false 52 } 53 val erasure = context.processingEnv.typeUtils.erasure(declared) 54 // we don't want to return paged list unless explicitly requested 55 return context.processingEnv.typeUtils.isAssignable(livePagedListTypeMirror, erasure) 56 } 57}