opennlp.fieldspring.tr.util.IOUtil.java Source code

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Here is the source code for opennlp.fieldspring.tr.util.IOUtil.java

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///////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2007 Jason Baldridge, The University of Texas at Austin
//
//  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 opennlp.fieldspring.tr.util;

import java.io.*;
import java.util.zip.*;
import org.apache.commons.compress.compressors.bzip2.*;

/**
 * Handy methods for interacting with the file system and running commands.
 *
 * @author     Jason Baldridge
 * @created    April 15, 2004
 */
public class IOUtil {

    /**
     * Write a string to a specified file.
     *
     * @param  contents  The string containing the contents of the file
     * @param  outfile   The File object identifying the location of the file
     */
    public static void writeStringToFile(String contents, File outfile) {
        try {
            BufferedWriter bw = new BufferedWriter(new FileWriter(outfile));
            bw.write(contents);
            bw.flush();
            bw.close();
        } catch (IOException ioe) {
            System.out.println("Input error writing to " + outfile.getName());
        }
        return;
    }

    /**
     * Reads a file as a single String all in one. Based on code snippet
     * found on web (http://snippets.dzone.com/posts/show/1335).  Reads raw bytes;
     * doesn't do any conversion (e.g. using UTF-8 or whatever).
     *
     * @param  infile  The File object identifying the location of the file
     */
    public static String readFileAsString(File infile) throws java.io.IOException {
        byte[] buffer = new byte[(int) infile.length()];
        FileInputStream f = new FileInputStream(infile);
        f.read(buffer);
        return new String(buffer);
    }

    /**
     * Calls runCommand/2 assuming that wait=true.
     *
     * @param  cmd  The string containing the command to execute
     */
    public static void runCommand(String cmd) {
        runCommand(cmd, true);
    }

    /**
     * Run a command with the option of waiting for it to finish.
     *
     * @param  cmd  The string containing the command to execute
     * @param  wait True if the caller should wait for this thread to 
     *              finish before continuing, false otherwise.
     */
    public static void runCommand(String cmd, boolean wait) {
        try {
            System.out.println("Running command: " + cmd);
            Process proc = Runtime.getRuntime().exec(cmd);

            // This needs to be done, otherwise some processes fill up
            // some Java buffer and make it so the spawned process
            // doesn't complete.
            BufferedReader br = new BufferedReader(new InputStreamReader(proc.getInputStream()));

            String line = null;
            while ((line = br.readLine()) != null) {
                // while (br.readLine() != null) {
                // just eat up the inputstream

                // Use this if you want to see the output from running
                // the command.
                System.out.println(line);
            }

            if (wait) {
                try {
                    proc.waitFor();
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                }
            }
            proc.getInputStream().close();
            proc.getOutputStream().close();
            proc.getErrorStream().close();
        } catch (IOException e) {
            System.out.println("Unable to run command: " + cmd);
        }
    }

    /**
     * Create a buffered reader from a file. If the file ends with .bz2 or .gz,
     * it is automatically uncompressed.
     */
    public static BufferedReader createBufferedReader(File file) throws IOException {
        // It is important to insert a BufferedInputStream between the
        // basic FileInputStream and the decompressor; not doing this leads
        // to a 100x slowdown in bzip2 decompression.
        InputStream istream = new BufferedInputStream(new FileInputStream(file));
        InputStream cstream;
        String fnlower = file.toString().toLowerCase();
        if (fnlower.endsWith(".bz2"))
            cstream = new BZip2CompressorInputStream(istream);
        else if (fnlower.endsWith(".gz"))
            cstream = new GZIPInputStream(istream);
        else
            cstream = istream;
        return new BufferedReader(new InputStreamReader(cstream, "UTF-8"));
    }

    /**
     * Create a buffered reader from a file. If the file ends with .bz2 or .gz,
     * it is automatically uncompressed.
     */
    public static BufferedReader createBufferedReader(String file) throws IOException {
        return createBufferedReader(new File(file));
    }
}