/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.ambari.view.huetoambarimigration.persistence.utils;
import org.apache.ambari.view.ViewContext;
import org.apache.ambari.view.huetoambarimigration.persistence.DataStoreStorage;
import org.apache.ambari.view.huetoambarimigration.persistence.LocalKeyValueStorage;
import org.apache.ambari.view.huetoambarimigration.persistence.Storage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.HashMap;
import java.util.Map;
/**
* Storage factory, creates storage of Local or Persistence API type.
* Type depends on context configuration: if "dataworker.storagePath" is set,
* storage of Local type will be created. Otherwise, Persistence API will be used.
*
* Storage is singleton.
*/
public class StorageUtil {
private Storage storageInstance = null;
protected final static Logger LOG =
LoggerFactory.getLogger(StorageUtil.class);
private static Map<String, StorageUtil> viewSingletonObjects = new HashMap<String, StorageUtil>();
public static StorageUtil getInstance(ViewContext context) {
if (!viewSingletonObjects.containsKey(context.getInstanceName()))
viewSingletonObjects.put(context.getInstanceName(), new StorageUtil(context));
return viewSingletonObjects.get(context.getInstanceName());
}
public static void dropAllConnections() {
viewSingletonObjects.clear();
}
private ViewContext context;
/**
* Constructor of storage util
* @param context View Context instance
*/
public StorageUtil(ViewContext context) {
this.context = context;
}
/**
* Get storage instance. If one is not created, creates instance.
* @return storage instance
*/
public synchronized Storage getStorage() {
if (storageInstance == null) {
String fileName = context.getProperties().get("dataworker.storagePath");
if (fileName != null) {
LOG.debug("Using local storage in " + fileName + " to store data");
// If specifed, use LocalKeyValueStorage - key-value file based storage
storageInstance = new LocalKeyValueStorage(context);
} else {
LOG.debug("Using Persistence API to store data");
// If not specifed, use ambari-views Persistence API
storageInstance = new DataStoreStorage(context);
}
}
return storageInstance;
}
/**
* Set storage to use across all application.
* Used in unit tests.
* @param storage storage instance
*/
public void setStorage(Storage storage) {
storageInstance = storage;
}
}