gov.nasa.ensemble.common.EnsembleDirectoryWalker.java Source code

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Here is the source code for gov.nasa.ensemble.common.EnsembleDirectoryWalker.java

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/*******************************************************************************
 * Copyright 2014 United States Government as represented by the
 * Administrator of the National Aeronautics and Space Administration.
 * All Rights Reserved.
 * 
 * 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 gov.nasa.ensemble.common;

import gov.nasa.ensemble.common.logging.LogUtil;

import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.Collection;
import java.util.Queue;
import java.util.concurrent.BlockingQueue;

import org.apache.commons.io.DirectoryWalker;

/**
 * Utility made for streaming files into a queue as they are discovered on the filesystem.
 * 
 * @author mpowell
 * 
 */
public class EnsembleDirectoryWalker extends DirectoryWalker {

    private final File directory;
    private final FileFilter filter;

    public EnsembleDirectoryWalker(File directory) {
        this(directory, new FileFilter() {

            @Override
            public boolean accept(File pathname) {
                return true;
            }
        });
    }

    public EnsembleDirectoryWalker(String filePath, FileFilter filter) {
        this(new File(filePath), filter);
    }

    public EnsembleDirectoryWalker(File directory, FileFilter filter) {
        this.directory = directory;
        this.filter = filter;
    }

    public void start(Queue<String> foundFiles) throws IOException {
        walk(directory, foundFiles);
    }

    @Override
    protected void handleFile(File file, int depth, Collection results) {
        if (filter.accept(file))
            if (results instanceof BlockingQueue) {
                try {
                    ((BlockingQueue) results).put(file.getAbsolutePath());
                } catch (InterruptedException e) {
                    LogUtil.error(e);
                }
            } else {
                results.add(file.getAbsolutePath());
            }
    }
}