/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package openbook.tools.util;
public class TextProcessingUtility {
/**
* Replaces special characters < and > in a string.
* The complexity is <em>not</em> to replace if the tags represent a hyperlink.
*/
public static String replaceHTMLSpecialCharacters(String txt) {
boolean inHyperlink = false;
StringBuilder buf = new StringBuilder();
int L = txt.length();
for (int i = 0; i < L; i++) {
char ch = txt.charAt(i);
if (!inHyperlink) {
if (ch == '<') {
String ahead = txt.substring(i, Math.min(i+3, L));
if (ahead.equalsIgnoreCase("<A ")) {
inHyperlink = true;
buf.append(ch);
} else {
buf.append(ch == '>' ? ">" : ch == '<' ? "<" : ch);
}
} else {
buf.append(ch == '>' ? ">" : ch == '<' ? "<" : ch);
}
} else { // inside a hyperlink tag. Do not translate characters
buf.append(ch);
if (ch == '>') {
String lookback = txt.substring(Math.max(0, i-4), i);
if (lookback.equalsIgnoreCase("</A")) {
inHyperlink = false;
}
}
}
}
return buf.toString();
}
}