htmlcodec.java

jGossip是一个简单而功能强大的Java论坛软件（消息板）

/*
 * $$Id: HtmlCodec.java,v 1.5 2004/01/26 11:32:05 bel70 Exp $$
 *
 * ***** BEGIN LICENSE BLOCK *****
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and 
 * limitations under the License.
 *
 * The Original Code is JGossip forum code.
 *
 * The Initial Developer of the Original Code is the JResearch, Org. 
 * Portions created by the Initial Developer are Copyright (C) 2004 
 * the Initial Developer. All Rights Reserved. 
 * 
 * Contributor(s): 
 *              Dmitry Belov <[e-mail]>
 *        
 * ***** END LICENSE BLOCK ***** */
package org.jresearch.gossip.util;

import sun.security.action.GetPropertyAction;

import java.io.UnsupportedEncodingException;

import java.net.URLEncoder;

import java.security.AccessController;


/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision: 1.5 $
 */
public class HtmlCodec {
    /**
     * It is the default array of symbols to be encoded into the html form.
     */
    public static char[] defSpecSymbols = new char[] {
            '"', '\'', '\\', ',', '<', '>', '(', ')', '.'
        };

    /**
     * This method is a wrapper for the <code>encode(String text , char[]
     * specSymbols)</code> method. It uses the defSpecialSymbols array as
     * special symbols.
     *
     * @param text It is the string to be encoded using the default array of
     *        special symbols.
     *
     * @return the encoded representation of the "text" parameter
     */
    public static String encode(final String text) {
        return encode(text, defSpecSymbols);
    }

    /**
     * This method is a wrapper for the <code>encode(String text , char[]
     * specSymbols)</code> method. It allows to specify special symbols as
     * elements of the String object ("String specSymbols" parameter).
     *
     * @param text It is the string to be encoded using special symbols from
     *        the "specSymbols" parameter.
     * @param specSymbols It is the set of special symbols to be encoded within
     *        the "text" parameter.
     *
     * @return the encoded representation of the "text" parameter
     */
    public static String encode(final String text, final String specSymbols) {
        final char[] cSpecSymbols;

        if ((specSymbols == null) || (specSymbols.length() == 0)) {
            cSpecSymbols = defSpecSymbols;
        } else {
            cSpecSymbols = specSymbols.toCharArray();
        }

        return encode(text, cSpecSymbols);
    }

    /**
     * It is the main encoding method. It encodes all special symbols in the
     * "text" parameter, using the specSymbols parameter as an array of
     * special symbols to be changed. AlSpecial symbols are translated to the
     * "&#xxx;" code, where the "xxx" part is the decimal code of the
     * correspondent special symbol.
     *
     * @param text It is the string to be encoded using special symbols from
     *        the "specSymbols" array.
     * @param specSymbols It is the array of special symbols to be encoded
     *        within the "text" parameter.
     *
     * @return the encoded representation of the "text" parameter
     */
    public static String encode(final String text, char[] specSymbols) {
        if (text == null) {
            return null;
        }

        if ((specSymbols == null) || (specSymbols.length == 0)) {
            specSymbols = defSpecSymbols;
        }

        StringBuffer buffer = new StringBuffer(text.length());
        char[] cText = text.toCharArray();

        for (int i = 0; i < cText.length; i++) {
            char cTextChar = cText[i]; // Speed up acess speed
            boolean isSpecial = false;

            for (int ss = 0; ss < specSymbols.length; ss++) {
                if (specSymbols[ss] == cTextChar) {
                    isSpecial = true;
                    buffer.append('&');
                    buffer.append('#');
                    buffer.append((int) cTextChar);
                    buffer.append(';');

                    break; // Exit the for cycle
                }
            }

            if (!isSpecial) {
                buffer.append(cTextChar);
            }
        }

        return buffer.toString();
    }

    /**
     * DOCUMENT ME!
     *
     * @param string DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public static String trim(String string) {
        return string.replaceAll("&nbsp;", " ").replaceAll("&#xA0;", " ").trim();
    }

    /**
     * It is a wrapper method for converting URL strings into the
     * "x-www-form-urlencoded"  MIME format. This method is placed here to
     * standardize html encoding only, to access all functionality via one
     * class.
     *
     * @param url It is the string to be encoded using the standard
     *        <code>{@link java.net.URLEncoder}</code> class.
     *
     * @return DOCUMENT ME!
     */
    public static String encodeURL(final String url) {
        try {
            return URLEncoder.encode(url,
                (String) AccessController.doPrivileged(
                    new GetPropertyAction("file.encoding")));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();

            return null;
        }
    }
}