/**
* 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.tools;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
/**
* Interface for excluding files from DistCp.
*
*/
public abstract class CopyFilter {
/**
* Default initialize method does nothing.
*/
public void initialize() {}
/**
* Predicate to determine if a file can be excluded from copy.
*
* @param path a Path to be considered for copying
* @return boolean, true to copy, false to exclude
*/
public abstract boolean shouldCopy(Path path);
/**
* Public factory method which returns the appropriate implementation of
* CopyFilter.
*
* @param conf DistCp configuratoin
* @return An instance of the appropriate CopyFilter
*/
public static CopyFilter getCopyFilter(Configuration conf) {
String filtersFilename = conf.get(DistCpConstants.CONF_LABEL_FILTERS_FILE);
if (filtersFilename == null) {
return new TrueCopyFilter();
} else {
String filterFilename = conf.get(
DistCpConstants.CONF_LABEL_FILTERS_FILE);
return new RegexCopyFilter(filterFilename);
}
}
}