| // Copyright (C) 2012 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.gerrit.extensions.registration; |
| |
| import com.google.gerrit.common.Nullable; |
| import com.google.inject.Binding; |
| import com.google.inject.Inject; |
| import com.google.inject.Injector; |
| import com.google.inject.Key; |
| import com.google.inject.Provider; |
| import com.google.inject.ProvisionException; |
| import com.google.inject.TypeLiteral; |
| import java.util.List; |
| |
| class DynamicItemProvider<T> implements Provider<DynamicItem<T>> { |
| private final TypeLiteral<T> type; |
| private final Key<DynamicItem<T>> key; |
| |
| @Inject private Injector injector; |
| |
| DynamicItemProvider(TypeLiteral<T> type, Key<DynamicItem<T>> key) { |
| this.type = type; |
| this.key = key; |
| } |
| |
| @Override |
| public DynamicItem<T> get() { |
| return new DynamicItem<>(key, find(injector, type), PluginName.GERRIT); |
| } |
| |
| @Nullable |
| private static <T> Provider<T> find(Injector src, TypeLiteral<T> type) { |
| List<Binding<T>> bindings = src.findBindingsByType(type); |
| if (bindings != null && bindings.size() == 1) { |
| return bindings.get(0).getProvider(); |
| } else if (bindings != null && bindings.size() > 1) { |
| throw new ProvisionException( |
| String.format( |
| "Multiple providers bound for DynamicItem<%s>\n" |
| + "This is not allowed; check the server configuration.", |
| type)); |
| } else { |
| return null; |
| } |
| } |
| } |