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/*
* Static File routines.
* Copyright (C) 2002 Stephen Ostermiller
* http://ostermiller.org/contact.pl?regarding=Java+Utilities
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* See COPYING.TXT for details.
*/
import java.io.*;
import java.text.MessageFormat;
import java.util.ResourceBundle;
import java.util.Locale;
/**
* Utilities for File manipulation.
* More information about this class is available from <a target="_top" href=
* "http://ostermiller.org/utils/FileHelper.html">ostermiller.org</a>.
*
* @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
* @since ostermillerutils 1.00.00
*/
public class FileHelper {
/**
* Locale specific strings displayed to the user.
*
* @since ostermillerutils 1.00.00
*/
protected static ResourceBundle labels = ResourceBundle.getBundle("com.Ostermiller.util.FileHelper", Locale.getDefault());
/**
* Move a file from one location to another. An attempt is made to rename
* the file and if that fails, the file is copied and the old file deleted.
*
* If the destination file already exists, an exception will be thrown.
*
* @param from file which should be moved.
* @param to desired destination of the file.
* @throws IOException if an error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static void move(File from, File to) throws IOException {
move(from, to, false);
}
/**
* Move a file from one location to another. An attempt is made to rename
* the file and if that fails, the file is copied and the old file deleted.
*
* @param from file which should be moved.
* @param to desired destination of the file.
* @param overwrite If false, an exception will be thrown rather than overwrite a file.
* @throws IOException if an error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static void move(File from, File to, boolean overwrite) throws IOException {
if (to.exists()){
if (overwrite){
if (!to.delete()){
throw new IOException(
MessageFormat.format(
labels.getString("deleteerror"),
(Object[])new String[] {
to.toString()
}
)
);
}
} else {
throw new IOException(
MessageFormat.format(
labels.getString("alreadyexistserror"),
(Object[])new String[] {
to.toString()
}
)
);
}
}
if (from.renameTo(to)) return;
InputStream in = null;
OutputStream out = null;
try {
in = new FileInputStream(from);
out = new FileOutputStream(to);
copy(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
if (!from.delete()){
throw new IOException(
MessageFormat.format(
labels.getString("deleteoriginalerror"),
(Object[])new String[] {
from.toString(),
to.toString()
}
)
);
}
} finally {
if (in != null){
in.close();
in = null;
}
if (out != null){
out.flush();
out.close();
out = null;
}
}
}
/**
* Buffer size when reading from input stream.
*
* @since ostermillerutils 1.00.00
*/
private final static int BUFFER_SIZE = 1024;
/**
* Copy the data from the input stream to the output stream.
*
* @param in data source
* @param out data destination
* @throws IOException in an input or output error occurs
*
* @since ostermillerutils 1.00.00
*/
private static void copy(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[BUFFER_SIZE];
int read;
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
}
}
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