org.apache.tajo.util.FileUtil.java Source code

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Here is the source code for org.apache.tajo.util.FileUtil.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.apache.tajo.util;

import org.apache.commons.logging.Log;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.apache.tajo.conf.TajoConf;

import java.io.*;
import java.nio.charset.Charset;

/**
 * Simple File Utilities
 */
public class FileUtil {

    public static String readTextFile(File file) throws IOException {
        StringBuilder fileData = new StringBuilder(1000);
        BufferedReader reader = new BufferedReader(new FileReader(file));
        char[] buf = new char[1024];
        int numRead;
        try {
            while ((numRead = reader.read(buf)) != -1) {
                String readData = String.valueOf(buf, 0, numRead);
                fileData.append(readData);
                buf = new char[1024];
            }
        } finally {
            IOUtils.cleanup(null, reader);
        }
        return fileData.toString();
    }

    /**
     * Write a string into a file
     *
     * @param text
     * @param path File path
     * @throws IOException
     */
    public static void writeTextToFile(String text, Path path) throws IOException {
        FileSystem fs = path.getFileSystem(new TajoConf());
        if (!fs.exists(path.getParent())) {
            fs.mkdirs(path.getParent());
        }
        FSDataOutputStream out = fs.create(path);
        out.write(text.getBytes());
        out.close();
    }

    public static String readTextFromStream(InputStream inputStream) throws IOException {
        try {
            StringBuilder fileData = new StringBuilder(1000);
            byte[] buf = new byte[1024];
            int numRead;
            while ((numRead = inputStream.read(buf)) != -1) {
                String readData = new String(buf, 0, numRead, Charset.defaultCharset());
                fileData.append(readData);
            }
            return fileData.toString();
        } finally {
            IOUtils.closeStream(inputStream);
        }
    }

    public static void writeTextToStream(String text, OutputStream outputStream) throws IOException {
        try {
            outputStream.write(text.getBytes());
        } finally {
            IOUtils.closeStream(outputStream);
        }
    }

    public static String humanReadableByteCount(long bytes, boolean si) {
        int unit = si ? 1000 : 1024;
        if (bytes < unit)
            return bytes + " B";
        int exp = (int) (Math.log(bytes) / Math.log(unit));
        String pre = (si ? "kMGTPE" : "KMGTPE").charAt(exp - 1) + (si ? "" : "i");
        return String.format("%.1f %sB", bytes / Math.pow(unit, exp), pre);
    }

    /**
     * Close the Closeable objects and <b>ignore</b> any {@link IOException} or
     * null pointers. Must only be used for cleanup in exception handlers.
     *
     * @param log the log to record problems to at debug level. Can be null.
     * @param closeables the objects to close
     */
    public static void cleanup(Log log, java.io.Closeable... closeables) {
        for (java.io.Closeable c : closeables) {
            if (c != null) {
                try {
                    c.close();
                } catch (IOException e) {
                    if (log != null && log.isDebugEnabled()) {
                        log.debug("Exception in closing " + c, e);
                    }
                }
            }
        }
    }

    /**
     * Close the Closeable objects and <b>throw</b> first {@link IOException}, if failed
     * @param closeables the objects to close
     */
    public static void cleanupAndthrowIfFailed(java.io.Closeable... closeables) throws IOException {
        IOException ioe = null;

        for (java.io.Closeable c : closeables) {
            if (c != null) {
                try {
                    c.close();
                } catch (IOException e) {
                    if (ioe == null)
                        ioe = e;
                }
            }
        }

        if (ioe != null) {
            throw ioe;
        }
    }
}