org.roc.hdfs.bolt.rules.FileSizeRotationPolicy.java Source code

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Here is the source code for org.roc.hdfs.bolt.rules.FileSizeRotationPolicy.java

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/**
 * 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.roc.hdfs.bolt.rules;

import java.io.IOException;

import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * File rotation policy that will rotate files when a certain file size is
 * reached.
 * 
 * For example:
 * 
 * <pre>
 * // rotate when files reach 5MB
 * FileSizeRotationPolicy policy = new FileSizeRotationPolicy(5.0, Units.MB);
 * </pre>
 * 
 */
public class FileSizeRotationPolicy implements FileRotationPolicy {
    private static final Logger LOG = LoggerFactory.getLogger(FileSizeRotationPolicy.class);

    public static enum Units {

        KB((long) Math.pow(2, 10)), MB((long) Math.pow(2, 20)), GB((long) Math.pow(2, 30)), TB(
                (long) Math.pow(2, 40));

        private long byteCount;

        private Units(long byteCount) {
            this.byteCount = byteCount;
        }

        public long getByteCount() {
            return byteCount;
        }
    }

    private long maxBytes;

    public FileSizeRotationPolicy(long fileSizeBytes) {

        this.maxBytes = fileSizeBytes;
    }

    public FileSizeRotationPolicy(float count, Units units) {
        this.maxBytes = (long) (count * units.getByteCount());
    }

    // if true , file can be rotated
    @Override
    public boolean mark(FileSystem fs, Path path, FileNameFormat format) {
        long size = 0L;
        try {
            size = fs.getContentSummary(path).getLength();
        } catch (IOException e) {
            LOG.warn("Error when get file's length  ", e);
            return false;
        }
        if (size >= this.maxBytes) {
            return true;
        } else {
            return false;
        }
    }

}