freemarker.template.utility.HtmlEscape Maven / Gradle / Ivy
/*
* 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 freemarker.template.utility;
import java.io.IOException;
import java.io.Writer;
import java.util.Map;
import freemarker.template.TemplateTransformModel;
/**
* Performs an HTML escape of a given template fragment. Specifically,
* < > " and & are all turned into entities.
*
* Usage:
* From java:
*
* SimpleHash root = new SimpleHash();
*
* root.put( "htmlEscape", new freemarker.template.utility.HtmlEscape() );
*
* ...
*
*
* From your FreeMarker template:
*
*
* The following is HTML-escaped:
* <transform htmlEscape>
* <p>This paragraph has all HTML special characters escaped.</p>
* </transform>
*
* ...
*
*
* @see freemarker.template.utility.XmlEscape
*/
public class HtmlEscape implements TemplateTransformModel {
private static final char[] LT = "<".toCharArray();
private static final char[] GT = ">".toCharArray();
private static final char[] AMP = "&".toCharArray();
private static final char[] QUOT = """.toCharArray();
@Override
public Writer getWriter(final Writer out, Map args) {
return new Writer()
{
@Override
public void write(int c)
throws IOException {
switch(c)
{
case '<': out.write(LT, 0, 4); break;
case '>': out.write(GT, 0, 4); break;
case '&': out.write(AMP, 0, 5); break;
case '"': out.write(QUOT, 0, 6); break;
default: out.write(c);
}
}
@Override
public void write(char cbuf[], int off, int len)
throws IOException {
int lastoff = off;
int lastpos = off + len;
for (int i = off; i < lastpos; i++) {
switch (cbuf[i])
{
case '<': out.write(cbuf, lastoff, i - lastoff); out.write(LT, 0, 4); lastoff = i + 1; break;
case '>': out.write(cbuf, lastoff, i - lastoff); out.write(GT, 0, 4); lastoff = i + 1; break;
case '&': out.write(cbuf, lastoff, i - lastoff); out.write(AMP, 0, 5); lastoff = i + 1; break;
case '"': out.write(cbuf, lastoff, i - lastoff); out.write(QUOT, 0, 6); lastoff = i + 1; break;
}
}
int remaining = lastpos - lastoff;
if (remaining > 0) {
out.write(cbuf, lastoff, remaining);
}
}
@Override
public void flush() throws IOException {
out.flush();
}
@Override
public void close() {
}
};
}
}