Java String Quote quote(String string)

Description

From JSONObject.java, from which the copyright notice is the following: Copyright (c) 2002 JSON.org Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

License

Apache License

Parameter

Parameter	Description
string	A String

Return

A String correctly formatted for insertion in a JSON text.

Declaration

public static String quote(String string)

Method Source Code

//package com.java2s;
/**/*from w  w  w  . j  av a2s. c  o m*/
 * Copyright 2008 Jordi Hern?ndez Sell?s
 * 
 * Licensed 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.
 */

public class Main {
    /**
     * From JSONObject.java, from which the copyright notice is the following: 
     * 
     * Copyright (c) 2002 JSON.org
     * Permission is hereby granted, free of charge, to any person obtaining a copy
     * of this software and associated documentation files (the "Software"), to deal
     * in the Software without restriction, including without limitation the rights
     * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     * copies of the Software, and to permit persons to whom the Software is
     * furnished to do so, subject to the following conditions:
     *
     *
     * The above copyright notice and this permission notice shall be included in all
     * copies or substantial portions of the Software.
     * 
     * Produce a string in double quotes with backslash sequences in all the
     * right places. A backslash will be inserted within </, allowing JSON
     * text to be delivered in HTML. In JSON text, a string cannot contain a
     * control character or an unescaped quote or backslash.
     * @param string A String
     * @return  A String correctly formatted for insertion in a JSON text.
     */
    public static String quote(String string) {
        if (string == null || string.length() == 0) {
            return "\"\"";
        }
        int len = string.length();
        StringBuffer sb = new StringBuffer(len + 4);

        sb.append('"');
        sb.append(escape(string));
        sb.append('"');
        return sb.toString();
    }

    /**
     * Escapes a string so it is valid between double quotes in javascript. 
     * @param string
     * @return
     */
    public static String escape(String string) {
        char b;
        char c = 0;
        int i;
        int len = string.length();
        StringBuffer sb = new StringBuffer(len + 2);
        String t;
        for (i = 0; i < len; i += 1) {
            b = c;
            c = string.charAt(i);
            switch (c) {
            case '\\':
            case '"':
                sb.append('\\');
                sb.append(c);
                break;
            case '/':
                if (b == '<') {
                    sb.append('\\');
                }
                sb.append(c);
                break;
            case '\b':
                sb.append("\\b");
                break;
            case '\t':
                sb.append("\\t");
                break;
            case '\n':
                sb.append("\\n");
                break;
            case '\f':
                sb.append("\\f");
                break;
            case '\r':
                sb.append("\\r");
                break;
            default:
                if (c < ' ' || (c >= '\u0080' && c < '\u00a0') || (c >= '\u2000' && c < '\u2100')) {
                    t = "000" + Integer.toHexString(c);
                    sb.append("\\u" + t.substring(t.length() - 4));
                } else {
                    sb.append(c);
                }
            }
        }
        return sb.toString();
    }
}