/**
*
* 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.hadoop.hbase.regionserver;
import java.io.IOException;
import java.util.Collection;
import java.util.List;
/**
* Utility functions for region server storage layer.
*/
public class StoreUtils {
/**
* Creates a deterministic hash code for store file collection.
*/
public static Integer getDeterministicRandomSeed(final List<StoreFile> files) {
if (files != null && !files.isEmpty()) {
return files.get(0).getPath().getName().hashCode();
}
return null;
}
/**
* Determines whether any files in the collection are references.
*/
public static boolean hasReferences(final Collection<StoreFile> files) {
if (files != null && files.size() > 0) {
for (StoreFile hsf: files) {
if (hsf.isReference()) {
return true;
}
}
}
return false;
}
/**
* Gets lowest timestamp from candidate StoreFiles
*/
public static long getLowestTimestamp(final List<StoreFile> candidates)
throws IOException {
long minTs = Long.MAX_VALUE;
for (StoreFile storeFile : candidates) {
minTs = Math.min(minTs, storeFile.getModificationTimeStamp());
}
return minTs;
}
}