/*
* 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 org.apache.jackrabbit.commons.json;
/**
* JSON utilities.
*/
public class JsonUtil {
/**
* Generate a valid JSON string from the given <code>str</code>.
*
* @param str A String
* @return JSON string surrounded by double quotes.
* @see <a href="http://tools.ietf.org/html/rfc4627">RFC 4627</a>
*/
public static String getJsonString(String str) {
if (str == null || str.length() == 0) {
return "\"\"";
}
int len = str.length();
StringBuffer sb = new StringBuffer(len + 2);
// leading quote
sb.append('"');
// append passed string escaping characters as required
for (int i = 0; i < len; i++) {
char c = str.charAt(i);
switch (c) {
// reverse solidus and double quote
case '\\':
case '"':
sb.append('\\').append(c);
break;
// tab, line breaking chars and backspace
case '\b':
sb.append("\\b");
break;
case '\f':
sb.append("\\f");
break;
case '\n':
sb.append("\\n");
break;
case '\r':
sb.append("\\r");
break;
case '\t':
sb.append("\\t");
break;
// other control characters and 'unescaped'
default:
if (c < 32) {
// control characters except those already covered above.
String uc = Integer.toHexString(c);
sb.append("\\u");
int uLen = uc.length();
while (uLen++ < 4) {
sb.append('0');
}
sb.append(uc);
} else {
// unescaped = %x20-21 / %x23-5B / %x5D-10FFFF
sb.append(c);
}
}
}
// trailing quote
sb.append('"');
return sb.toString();
}
}