/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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 org.elasticsearch.script.mustache;
import com.github.mustachejava.DefaultMustacheFactory;
import com.github.mustachejava.MustacheException;
import java.io.IOException;
import java.io.Writer;
/**
* A MustacheFactory that does simple JSON escaping.
*/
public final class JsonEscapingMustacheFactory extends DefaultMustacheFactory {
@Override
public void encode(String value, Writer writer) {
try {
escape(value, writer);
} catch (IOException e) {
throw new MustacheException("Failed to encode value: " + value);
}
}
public static Writer escape(String value, Writer writer) throws IOException {
for (int i = 0; i < value.length(); i++) {
final char character = value.charAt(i);
if (isEscapeChar(character)) {
writer.write('\\');
}
writer.write(character);
}
return writer;
}
public static boolean isEscapeChar(char c) {
switch(c) {
case '\b':
case '\f':
case '\n':
case '\r':
case '"':
case '\\':
case '\u000B': // vertical tab
case '\t':
return true;
}
return false;
}
}