/* ========================================================================
* JCommon : a free general purpose class library for the Java(tm) platform
* ========================================================================
*
* (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ------------------------------
* SortedConfigurationWriter.java
* ------------------------------
* (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
*
* Original Author: Thomas Morgner;
* Contributor(s): -;
*
* $Id: SortedConfigurationWriter.java,v 1.4 2005/11/03 09:55:27 mungady Exp $
*
* Changes
* -------
*
*/
package org.jfree.util;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
/**
* Writes a <code>Configuration</code> instance into a property file, where
* the keys are sorted by their name. Writing sorted keys make it easier for
* users to find and change properties in the file.
*
* @author Thomas Morgner
*/
public class SortedConfigurationWriter {
/**
* A constant defining that text should be escaped in a way
* which is suitable for property keys.
*/
private static final int ESCAPE_KEY = 0;
/**
* A constant defining that text should be escaped in a way
* which is suitable for property values.
*/
private static final int ESCAPE_VALUE = 1;
/**
* A constant defining that text should be escaped in a way
* which is suitable for property comments.
*/
private static final int ESCAPE_COMMENT = 2;
/** The system-dependent End-Of-Line separator. */
private static final String END_OF_LINE = StringUtils.getLineSeparator();
/**
* The default constructor, does nothing.
*/
public SortedConfigurationWriter() {
}
/**
* Returns a description for the given key. This implementation returns
* null to indicate that no description should be written. Subclasses can
* overwrite this method to provide comments for every key. These descriptions
* will be included as inline comments.
*
* @param key the key for which a description should be printed.
* @return the description or null if no description should be printed.
*/
protected String getDescription(final String key) {
return null;
}
/**
* Saves the given configuration into a file specified by the given
* filename.
*
* @param filename the filename
* @param config the configuration
* @throws IOException if an IOError occurs.
*/
public void save(final String filename, final Configuration config)
throws IOException {
save(new File(filename), config);
}
/**
* Saves the given configuration into a file specified by the given
* file object.
*
* @param file the target file
* @param config the configuration
* @throws IOException if an IOError occurs.
*/
public void save(final File file, final Configuration config)
throws IOException {
final BufferedOutputStream out =
new BufferedOutputStream(new FileOutputStream(file));
save(out, config);
out.close();
}
/**
* Writes the configuration into the given output stream.
*
* @param outStream the target output stream
* @param config the configuration
* @throws IOException if writing fails.
*/
public void save(final OutputStream outStream, final Configuration config)
throws IOException {
final ArrayList names = new ArrayList();
// clear all previously set configuration settings ...
final Iterator defaults = config.findPropertyKeys("");
while (defaults.hasNext()) {
final String key = (String) defaults.next();
names.add(key);
}
Collections.sort(names);
final OutputStreamWriter out =
new OutputStreamWriter(outStream, "iso-8859-1");
for (int i = 0; i < names.size(); i++) {
final String key = (String) names.get(i);
final String value = config.getConfigProperty(key);
final String description = getDescription(key);
if (description != null) {
writeDescription(description, out);
}
saveConvert(key, ESCAPE_KEY, out);
out.write("=");
saveConvert(value, ESCAPE_VALUE, out);
out.write(END_OF_LINE);
}
out.flush();
}
/**
* Writes a descriptive comment into the given print writer.
*
* @param text the text to be written. If it contains more than
* one line, every line will be prepended by the comment character.
* @param writer the writer that should receive the content.
* @throws IOException if writing fails
*/
private void writeDescription(final String text, final Writer writer)
throws IOException {
// check if empty content ... this case is easy ...
if (text.length() == 0) {
return;
}
writer.write("# ");
writer.write(END_OF_LINE);
final LineBreakIterator iterator = new LineBreakIterator(text);
while (iterator.hasNext()) {
writer.write("# ");
saveConvert((String) iterator.next(), ESCAPE_COMMENT, writer);
writer.write(END_OF_LINE);
}
}
/**
* Performs the necessary conversion of an java string into a property
* escaped string.
*
* @param text the text to be escaped
* @param escapeMode the mode that should be applied.
* @param writer the writer that should receive the content.
* @throws IOException if writing fails
*/
private void saveConvert(final String text, final int escapeMode,
final Writer writer)
throws IOException {
final char[] string = text.toCharArray();
for (int x = 0; x < string.length; x++) {
final char aChar = string[x];
switch (aChar) {
case ' ':
{
if ((escapeMode != ESCAPE_COMMENT)
&& (x == 0 || escapeMode == ESCAPE_KEY)) {
writer.write('\\');
}
writer.write(' ');
break;
}
case '\\':
{
writer.write('\\');
writer.write('\\');
break;
}
case '\t':
{
if (escapeMode == ESCAPE_COMMENT) {
writer.write(aChar);
}
else {
writer.write('\\');
writer.write('t');
}
break;
}
case '\n':
{
writer.write('\\');
writer.write('n');
break;
}
case '\r':
{
writer.write('\\');
writer.write('r');
break;
}
case '\f':
{
if (escapeMode == ESCAPE_COMMENT) {
writer.write(aChar);
}
else {
writer.write('\\');
writer.write('f');
}
break;
}
case '#':
case '"':
case '!':
case '=':
case ':':
{
if (escapeMode == ESCAPE_COMMENT) {
writer.write(aChar);
}
else {
writer.write('\\');
writer.write(aChar);
}
break;
}
default:
if ((aChar < 0x0020) || (aChar > 0x007e)) {
writer.write('\\');
writer.write('u');
writer.write(HEX_CHARS[(aChar >> 12) & 0xF]);
writer.write(HEX_CHARS[(aChar >> 8) & 0xF]);
writer.write(HEX_CHARS[(aChar >> 4) & 0xF]);
writer.write(HEX_CHARS[aChar & 0xF]);
}
else {
writer.write(aChar);
}
}
}
}
/** A lookup-table. */
private static final char[] HEX_CHARS =
{'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
}