1 /* 2 * Copyright (C) 2015 Google, Inc. 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 package dagger.internal.codegen; 17 18 import com.google.common.collect.ImmutableList; 19 import java.util.ArrayDeque; 20 import java.util.Deque; 21 22 /** 23 * Utility code that looks for bindings matching a key in all subcomponents in a binding graph so 24 * that a user is advised that a binding exists elsewhere when it is not found in the current 25 * subgraph. If a binding matching a key exists in a sub- or sibling component, that is often what 26 * the user actually wants to use. 27 */ 28 class MissingBindingSuggestions { 29 /** 30 * Searches the entire binding graph from the top-level graph for a binding matching 31 * {@code key}. 32 */ 33 static ImmutableList<String> forKey(BindingGraph topLevelGraph, BindingKey key) { 34 ImmutableList.Builder<String> resolutions = new ImmutableList.Builder<>(); 35 Deque<BindingGraph> graphsToTry = new ArrayDeque<>(); 36 37 graphsToTry.add(topLevelGraph); 38 do { 39 BindingGraph graph = graphsToTry.removeLast(); 40 ResolvedBindings bindings = graph.resolvedBindings().get(key); 41 if ((bindings == null) || bindings.bindings().isEmpty()) { 42 graphsToTry.addAll(graph.subgraphs().values()); 43 } else { 44 resolutions.add("A binding with matching key exists in component: " 45 + graph.componentDescriptor().componentDefinitionType().getQualifiedName()); 46 } 47 } while (!graphsToTry.isEmpty()); 48 49 return resolutions.build(); 50 } 51 52 private MissingBindingSuggestions() {} 53 } 54
