Codec.java

Go to the documentation of this file.

/*
 * Gridarta MMORPG map editor for Crossfire, Daimonin and similar games.
 * Copyright (C) 2000-2023 The Gridarta Developers.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
package net.sf.gridarta.preferences;
 
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.jetbrains.annotations.NotNull;
 
public class Codec {
 
    @NotNull
    private static final Pattern @NotNull [] PATTERNS_ENCODE = { Pattern.compile("\\\\"), Pattern.compile("\r"), Pattern.compile("\n"), };
 
    @NotNull
    private static final String @NotNull [] REPLACEMENTS_ENCODE = { Matcher.quoteReplacement("\\\\"), Matcher.quoteReplacement("\\r"), Matcher.quoteReplacement("\\n"), };
 
    @NotNull
    private static final Pattern @NotNull [] PATTERNS_DECODE = { Pattern.compile("\\\\n"), Pattern.compile("\\\\r"), Pattern.compile("\\\\\\\\"), };
 
    @NotNull
    private static final String @NotNull [] REPLACEMENTS_DECODE = { Matcher.quoteReplacement("\n"), Matcher.quoteReplacement("\r"), Matcher.quoteReplacement("\\"), };
 
    private Codec() {
    }
 
    @NotNull
    public static String encode(@NotNull final String str) {
        final StringBuilder sb = new StringBuilder();
        for (int i = 0; i < str.length(); i++) {
            final char ch = str.charAt(i);
            switch (ch) {
            case '\r':
                sb.append("\\r");
                break;
 
            case '\n':
                sb.append("\\n");
                break;
 
            case '\\':
                sb.append("\\\\");
                break;
 
            default:
                sb.append(ch);
                break;
            }
        }
        return sb.toString();
    }
 
    @NotNull
    public static String decode(@NotNull final String str) {
        final StringBuilder sb = new StringBuilder();
        int i = 0;
        while (i < str.length()) {
            final char ch = str.charAt(i);
            if (ch == '\\' && i + 1 < str.length()) {
                i++;
                final char ch2 = str.charAt(i);
                switch (ch2) {
                case 'r':
                    sb.append('\r');
                    break;
 
                case 'n':
                    sb.append('\n');
                    break;
 
                case '\\':
                    sb.append('\\');
                    break;
 
                default:
                    // invalid => do not replace
                    sb.append('\\');
                    sb.append(ch2);
                    break;
                }
            } else {
                sb.append(ch);
            }
            i++;
        }
        return sb.toString();
    }
 
}