Java HTML Encode forHTMLTag(String aTagFragment)

Description

Replace characters having special meaning inside HTML tags with their escaped equivalents, using character entities such as '&'.

License

Open Source License

Parameter

Parameter	Description
aTagFragment	some HTML to be escaped

Return

escaped HTML

Declaration

private static String forHTMLTag(String aTagFragment) 

Method Source Code

//package com.java2s;
/*//  w  w w .  j a  v  a2s.  c om
 * RHQ Management Platform
 * Copyright (C) 2005-2012 Red Hat, Inc.
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation, and/or the GNU Lesser
 * General Public License, version 2.1, also as published by the Free
 * Software Foundation.
 *
 * 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 and the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * and the GNU Lesser 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.
 */

import java.text.CharacterIterator;
import java.text.StringCharacterIterator;

public class Main {
    /**
     * Replace characters having special meaning <em>inside</em> HTML tags with
     * their escaped equivalents, using character entities such as
     * <tt>'&amp;'</tt>.
     * <P>
     * The escaped characters are :
     * <ul>
     * <li><
     * <li>>
     * <li>"
     * <li>'
     * <li>\
     * <li>&
     * </ul>
     * <P>
     * This method ensures that arbitrary text appearing inside a tag does not
     * "confuse" the tag. For example, <tt>HREF='Blah.do?Page=1&Sort=ASC'</tt>
     * does not comply with strict HTML because of the ampersand, and should be
     * changed to <tt>HREF='Blah.do?Page=1&amp;Sort=ASC'</tt>. This is
     * commonly seen in building query strings. (In JSTL, the c:url tag performs
     * this task automatically.)
     * 
     * forHTMLTag is copy-n-pasted from: http://www.javapractices.com/Topic96.cjp 
     * used to be in our util.StringUtil, we should really use jakarta's <code>StringEscapeUtils.escapeHTML()</code> 
     * method, however, at this time we do not want to pull in the entire 
     * Commons Lang API dependency for just one method.
     * 
     * @param aTagFragment
     *           some HTML to be escaped
     * @return escaped HTML
     */
    private static String forHTMLTag(String aTagFragment) {
        final StringBuffer result = new StringBuffer();

        final StringCharacterIterator iterator = new StringCharacterIterator(
                aTagFragment);

        for (char character = iterator.current(); character != CharacterIterator.DONE; character = iterator
                .next()) {
            switch (character) {
            case '<':
                result.append("&lt;");
                break;
            case '>':
                result.append("&gt;");
                break;
            case '\"':
                result.append("&quot;");
                break;
            case '\'':
                result.append("&#039;");
                break;
            case '\\':
                result.append("&#092;");
                break;
            case '&':
                result.append("&amp;");
                break;
            case '|':
                result.append("&#124;");
                break;
            case ',':
                result.append("&#44;");
                break;
            default:
                // the char is not a special one add it to the result as is
                result.append(character);
                break;
            }
        }
        return result.toString();
    }
}

Related

1. encodeHTML(String s)
2. forHTML(final String aText)
3. forHTML(String aText)
4. forHtmlComplete(final String aText)
5. forHTMLTag(String aTagFragment)
6. html(String text)
7. html(String text)
8. html_encode(String input_string)
9. HTMLBREncode(String str)