jsonobject.java

很好的json数据处理格式

    }

    /**
     * Remove a name and its value, if present.
     * @param key The name to be removed.
     * @return The value that was associated with the name,
     * or null if there was no value.
     */
    public Object remove(String key) {
        return this.map.remove(key);
    }
   
    /**
     * Get an enumeration of the keys of the JSONObject.
     * The keys will be sorted alphabetically.
     *
     * @return An iterator of the keys.
     */
    public Iterator sortedKeys() {
      return new TreeSet(this.map.keySet()).iterator();
    }

    /**
     * Try to convert a string into a number, boolean, or null. If the string
     * can't be converted, return the string.
     * @param s A String.
     * @return A simple JSON value.
     */
    static public Object stringToValue(String s) {
        if (s.equals("")) {
            return s;
        }
        if (s.equalsIgnoreCase("true")) {
            return Boolean.TRUE;
        }
        if (s.equalsIgnoreCase("false")) {
            return Boolean.FALSE;
        }
        if (s.equalsIgnoreCase("null")) {
            return JSONObject.NULL;
        }

        /*
         * If it might be a number, try converting it. We support the 0- and 0x-
         * conventions. If a number cannot be produced, then the value will just
         * be a string. Note that the 0-, 0x-, plus, and implied string
         * conventions are non-standard. A JSON parser is free to accept
         * non-JSON forms as long as it accepts all correct JSON forms.
         */

        char b = s.charAt(0);
        if ((b >= '0' && b <= '9') || b == '.' || b == '-' || b == '+') {
            if (b == '0') {
                if (s.length() > 2 &&
                        (s.charAt(1) == 'x' || s.charAt(1) == 'X')) {
                    try {
                        return new Integer(Integer.parseInt(s.substring(2),
                                16));
                    } catch (Exception e) {
                        /* Ignore the error */
                    }
                } else {
                    try {
                        return new Integer(Integer.parseInt(s, 8));
                    } catch (Exception e) {
                        /* Ignore the error */
                    }
                }
            }
            try {
                return new Integer(s);
            } catch (Exception e) {
                try {
                    return new Long(s);
                } catch (Exception f) {
                    try {
                        return new Double(s);
                    }  catch (Exception g) {
                    	/* Ignore the error */
                    }
                }
            }
        }
        return s;
    }
    
    
    /**
     * Throw an exception if the object is an NaN or infinite number.
     * @param o The object to test.
     * @throws JSONException If o is a non-finite number.
     */
    static void testValidity(Object o) throws JSONException {
        if (o != null) {
            if (o instanceof Double) {
                if (((Double)o).isInfinite() || ((Double)o).isNaN()) {
                    throw new JSONException(
                        "JSON does not allow non-finite numbers.");
                }
            } else if (o instanceof Float) {
                if (((Float)o).isInfinite() || ((Float)o).isNaN()) {
                    throw new JSONException(
                        "JSON does not allow non-finite numbers.");
                }
            }
        }
    }


    /**
     * Produce a JSONArray containing the values of the members of this
     * JSONObject.
     * @param names A JSONArray containing a list of key strings. This
     * determines the sequence of the values in the result.
     * @return A JSONArray of values.
     * @throws JSONException If any of the values are non-finite numbers.
     */
    public JSONArray toJSONArray(JSONArray names) throws JSONException {
        if (names == null || names.length() == 0) {
            return null;
        }
        JSONArray ja = new JSONArray();
        for (int i = 0; i < names.length(); i += 1) {
            ja.put(this.opt(names.getString(i)));
        }
        return ja;
    }

    /**
     * Make a JSON text of this JSONObject. For compactness, no whitespace
     * is added. If this would not result in a syntactically correct JSON text,
     * then null will be returned instead.
     * <p>
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @return a printable, displayable, portable, transmittable
     *  representation of the object, beginning
     *  with <code>{</code>&nbsp;<small>(left brace)</small> and ending
     *  with <code>}</code>&nbsp;<small>(right brace)</small>.
     */
    public String toString() {
        try {
            Iterator     keys = keys();
            StringBuffer sb = new StringBuffer("{");

            while (keys.hasNext()) {
                if (sb.length() > 1) {
                    sb.append(',');
                }
                Object o = keys.next();
                sb.append(quote(o.toString()));
                sb.append(':');
                sb.append(valueToString(this.map.get(o)));
            }
            sb.append('}');
            return sb.toString();
        } catch (Exception e) {
            return null;
        }
    }


    /**
     * Make a prettyprinted JSON text of this JSONObject.
     * <p>
     * Warning: This method assumes that the data structure is acyclical.
     * @param indentFactor The number of spaces to add to each level of
     *  indentation.
     * @return a printable, displayable, portable, transmittable
     *  representation of the object, beginning
     *  with <code>{</code>&nbsp;<small>(left brace)</small> and ending
     *  with <code>}</code>&nbsp;<small>(right brace)</small>.
     * @throws JSONException If the object contains an invalid number.
     */
    public String toString(int indentFactor) throws JSONException {
        return toString(indentFactor, 0);
    }


    /**
     * Make a prettyprinted JSON text of this JSONObject.
     * <p>
     * Warning: This method assumes that the data structure is acyclical.
     * @param indentFactor The number of spaces to add to each level of
     *  indentation.
     * @param indent The indentation of the top level.
     * @return a printable, displayable, transmittable
     *  representation of the object, beginning
     *  with <code>{</code>&nbsp;<small>(left brace)</small> and ending
     *  with <code>}</code>&nbsp;<small>(right brace)</small>.
     * @throws JSONException If the object contains an invalid number.
     */
    String toString(int indentFactor, int indent) throws JSONException {
        int j;
        int n = length();
        if (n == 0) {
            return "{}";
        }
        Iterator     keys = sortedKeys();
        StringBuffer sb = new StringBuffer("{");
        int          newindent = indent + indentFactor;
        Object       o;
        if (n == 1) {
            o = keys.next();
            sb.append(quote(o.toString()));
            sb.append(": ");
            sb.append(valueToString(this.map.get(o), indentFactor,
                    indent));
        } else {
            while (keys.hasNext()) {
                o = keys.next();
                if (sb.length() > 1) {
                    sb.append(",\n");
                } else {
                    sb.append('\n');
                }
                for (j = 0; j < newindent; j += 1) {
                    sb.append(' ');
                }
                sb.append(quote(o.toString()));
                sb.append(": ");
                sb.append(valueToString(this.map.get(o), indentFactor,
                        newindent));
            }
            if (sb.length() > 1) {
                sb.append('\n');
                for (j = 0; j < indent; j += 1) {
                    sb.append(' ');
                }
            }
        }
        sb.append('}');
        return sb.toString();
    }


    /**
     * Make a JSON text of an Object value. If the object has an
     * value.toJSONString() method, then that method will be used to produce
     * the JSON text. The method is required to produce a strictly
     * conforming text. If the object does not contain a toJSONString
     * method (which is the most common case), then a text will be
     * produced by other means. If the value is an array or Collection,
     * then a JSONArray will be made from it and its toJSONString method
     * will be called. If the value is a MAP, then a JSONObject will be made
     * from it and its toJSONString method will be called. Otherwise, the
     * value's toString method will be called, and the result will be quoted.
     *
     * <p>
     * Warning: This method assumes that the data structure is acyclical.
     * @param value The value to be serialized.
     * @return a printable, displayable, transmittable
     *  representation of the object, beginning
     *  with <code>{</code>&nbsp;<small>(left brace)</small> and ending
     *  with <code>}</code>&nbsp;<small>(right brace)</small>.
     * @throws JSONException If the value is or contains an invalid number.
     */
    static String valueToString(Object value) throws JSONException {
        if (value == null || value.equals(null)) {
            return "null";
        }
        if (value instanceof JSONString) {
            Object o;
            try {
                o = ((JSONString)value).toJSONString();
            } catch (Exception e) {
                throw new JSONException(e);
            }
            if (o instanceof String) {
                return (String)o;
            }
            throw new JSONException("Bad value from toJSONString: " + o);
        }
        if (value instanceof Number) {
            return numberToString((Number) value);
        }
        if (value instanceof Boolean || value instanceof JSONObject ||
                value instanceof JSONArray) {
            return value.toString();
        }
        if (value instanceof Map) {
            return new JSONObject((Map)value).toString();
        }
        if (value instanceof Collection) {
            return new JSONArray((Collection)value).toString();
        }
        if (value.getClass().isArray()) {
            return new JSONArray(value).toString();
        }
        return quote(value.toString());
    }


    /**
     * Make a prettyprinted JSON text of an object value.
     * <p>
     * Warning: This method assumes that the data structure is acyclical.
     * @param value The value to be serialized.
     * @param indentFactor The number of spaces to add to each level of
     *  indentation.
     * @param indent The indentation of the top level.
     * @return a printable, displayable, transmittable
     *  representation of the object, beginning
     *  with <code>{</code>&nbsp;<small>(left brace)</small> and ending
     *  with <code>}</code>&nbsp;<small>(right brace)</small>.
     * @throws JSONException If the object contains an invalid number.
     */
     static String valueToString(Object value, int indentFactor, int indent)
            throws JSONException {
        if (value == null || value.equals(null)) {
            return "null";
        }
        try {
            if (value instanceof JSONString) {
                Object o = ((JSONString)value).toJSONString();
                if (o instanceof String) {
                    return (String)o;
                }
            }
        } catch (Exception e) {
            /* forget about it */
        }
        if (value instanceof Number) {
            return numberToString((Number) value);
        }
        if (value instanceof Boolean) {
            return value.toString();
        }
        if (value instanceof JSONObject) {
            return ((JSONObject)value).toString(indentFactor, indent);
        }
        if (value instanceof JSONArray) {
            return ((JSONArray)value).toString(indentFactor, indent);
        }
        if (value instanceof Map) {
            return new JSONObject((Map)value).toString(indentFactor, indent);
        }
        if (value instanceof Collection) {
            return new JSONArray((Collection)value).toString(indentFactor, indent);
        }
        if (value.getClass().isArray()) {
            return new JSONArray(value).toString(indentFactor, indent);
        }
        return quote(value.toString());
    }


     /**
      * Write the contents of the JSONObject as JSON text to a writer.
      * For compactness, no whitespace is added.
      * <p>
      * Warning: This method assumes that the data structure is acyclical.
      *
      * @return The writer.
      * @throws JSONException
      */
     public Writer write(Writer writer) throws JSONException {
        try {
            boolean  b = false;
            Iterator keys = keys();
            writer.write('{');

            while (keys.hasNext()) {
                if (b) {
                    writer.write(',');
                }
                Object k = keys.next();
                writer.write(quote(k.toString()));
                writer.write(':');
                Object v = this.map.get(k);
                if (v instanceof JSONObject) {
                    ((JSONObject)v).write(writer);
                } else if (v instanceof JSONArray) {
                    ((JSONArray)v).write(writer);
                } else {
                    writer.write(valueToString(v));
                }
                b = true;
            }
            writer.write('}');
            return writer;
        } catch (IOException e) {
            throw new JSONException(e);
        }
     }
}