blob: 7ed7077e6be2c986f69bd506fb391488a0e116ac [file] [log] [blame]
// 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;
}
}
}