/*
* Copyright (c) 2013 Google Inc.
*
* 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.api.client.util.store;
import java.io.IOException;
import java.io.Serializable;
/**
* Thread-safe in-memory implementation of a data store factory.
*
* <p>
* For convenience, a default global instance is provided in {@link #getDefaultInstance()}.
* </p>
*
* @since 1.16
* @author Yaniv Inbar
*/
public class MemoryDataStoreFactory extends AbstractDataStoreFactory {
@Override
protected <V extends Serializable> DataStore<V> createDataStore(String id) throws IOException {
return new MemoryDataStore<V>(this, id);
}
/** Returns a global thread-safe instance. */
public static MemoryDataStoreFactory getDefaultInstance() {
return InstanceHolder.INSTANCE;
}
/** Holder for the result of {@link #getDefaultInstance()}. */
static class InstanceHolder {
static final MemoryDataStoreFactory INSTANCE = new MemoryDataStoreFactory();
}
static class MemoryDataStore<V extends Serializable> extends AbstractMemoryDataStore<V> {
MemoryDataStore(MemoryDataStoreFactory dataStore, String id) {
super(dataStore, id);
}
@Override
public MemoryDataStoreFactory getDataStoreFactory() {
return (MemoryDataStoreFactory) super.getDataStoreFactory();
}
}
}