plugins/jibu-json/src/main/java/org/gaixie/jibu/json/CDL.java

   1 package org.gaixie.jibu.json;
   2
   3 /*
   4   Copyright (c) 2002 JSON.org
   5
   6   Permission is hereby granted, free of charge, to any person obtaining a copy
   7   of this software and associated documentation files (the "Software"), to deal
   8   in the Software without restriction, including without limitation the rights
   9   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10   copies of the Software, and to permit persons to whom the Software is
  11   furnished to do so, subject to the following conditions:
  12
  13   The above copyright notice and this permission notice shall be included in all
  14   copies or substantial portions of the Software.
  15
  16   The Software shall be used for Good, not Evil.
  17
  18   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24   SOFTWARE.
  25 */
  26
  27 /**
  28  * This provides static methods to convert comma delimited text into a
  29  * JSONArray, and to covert a JSONArray into comma delimited text. Comma
  30  * delimited text is a very popular format for data interchange. It is
  31  * understood by most database, spreadsheet, and organizer programs.
  32  * <p>
  33  * Each row of text represents a row in a table or a data record. Each row
  34  * ends with a NEWLINE character. Each row contains one or more values.
  35  * Values are separated by commas. A value can contain any character except
  36  * for comma, unless is is wrapped in single quotes or double quotes.
  37  * <p>
  38  * The first row usually contains the names of the columns.
  39  * <p>
  40  * A comma delimited list can be converted into a JSONArray of JSONObjects.
  41  * The names for the elements in the JSONObjects can be taken from the names
  42  * in the first row.
  43  * @author JSON.org
  44  * @version 2009-09-11
  45  */
  46 public class CDL {
  47
  48     /**
  49      * Get the next value. The value can be wrapped in quotes. The value can
  50      * be empty.
  51      * @param x A JSONTokener of the source text.
  52      * @return The value string, or null if empty.
  53      * @throws JSONException if the quoted string is badly formed.
  54      */
  55     private static String getValue(JSONTokener x) throws JSONException {
  56         char c;
  57         char q;
  58         StringBuffer sb;
  59         do {
  60             c = x.next();
  61         } while (c == ' ' || c == '\t');
  62         switch (c) {
  63         case 0:
  64             return null;
  65         case '"':
  66         case '\'':
  67             q = c;
  68         sb = new StringBuffer();
  69         for (;;) {
  70             c = x.next();
  71             if (c == q) {
  72                 break;
  73             }
  74             if (c == 0 || c == '\n' || c == '\r') {
  75                 throw x.syntaxError("Missing close quote '" + q + "'.");
  76             }
  77             sb.append(c);
  78         }
  79         return sb.toString();
  80         case ',':
  81             x.back();
  82             return "";
  83         default:
  84             x.back();
  85             return x.nextTo(',');
  86         }
  87     }
  88
  89     /**
  90      * Produce a JSONArray of strings from a row of comma delimited values.
  91      * @param x A JSONTokener of the source text.
  92      * @return A JSONArray of strings.
  93      * @throws JSONException
  94      */
  95     public static JSONArray rowToJSONArray(JSONTokener x) throws JSONException {
  96         JSONArray ja = new JSONArray();
  97         for (;;) {
  98             String value = getValue(x);
  99             char c = x.next();
 100             if (value == null ||
 101                 (ja.length() == 0 && value.length() == 0 && c != ',')) {
 102                 return null;
 103             }
 104             ja.put(value);
 105             for (;;) {
 106                 if (c == ',') {
 107                     break;
 108                 }
 109                 if (c != ' ') {
 110                     if (c == '\n' || c == '\r' || c == 0) {
 111                         return ja;
 112                     }
 113                     throw x.syntaxError("Bad character '" + c + "' (" +
 114                                         (int)c + ").");
 115                 }
 116                 c = x.next();
 117             }
 118         }
 119     }
 120
 121     /**
 122      * Produce a JSONObject from a row of comma delimited text, using a
 123      * parallel JSONArray of strings to provides the names of the elements.
 124      * @param names A JSONArray of names. This is commonly obtained from the
 125      *  first row of a comma delimited text file using the rowToJSONArray
 126      *  method.
 127      * @param x A JSONTokener of the source text.
 128      * @return A JSONObject combining the names and values.
 129      * @throws JSONException
 130      */
 131     public static JSONObject rowToJSONObject(JSONArray names, JSONTokener x)
 132         throws JSONException {
 133         JSONArray ja = rowToJSONArray(x);
 134         return ja != null ? ja.toJSONObject(names) :  null;
 135     }
 136
 137     /**
 138      * Produce a JSONArray of JSONObjects from a comma delimited text string,
 139      * using the first row as a source of names.
 140      * @param string The comma delimited text.
 141      * @return A JSONArray of JSONObjects.
 142      * @throws JSONException
 143      */
 144     public static JSONArray toJSONArray(String string) throws JSONException {
 145         return toJSONArray(new JSONTokener(string));
 146     }
 147
 148     /**
 149      * Produce a JSONArray of JSONObjects from a comma delimited text string,
 150      * using the first row as a source of names.
 151      * @param x The JSONTokener containing the comma delimited text.
 152      * @return A JSONArray of JSONObjects.
 153      * @throws JSONException
 154      */
 155     public static JSONArray toJSONArray(JSONTokener x) throws JSONException {
 156         return toJSONArray(rowToJSONArray(x), x);
 157     }
 158
 159     /**
 160      * Produce a JSONArray of JSONObjects from a comma delimited text string
 161      * using a supplied JSONArray as the source of element names.
 162      * @param names A JSONArray of strings.
 163      * @param string The comma delimited text.
 164      * @return A JSONArray of JSONObjects.
 165      * @throws JSONException
 166      */
 167     public static JSONArray toJSONArray(JSONArray names, String string)
 168         throws JSONException {
 169         return toJSONArray(names, new JSONTokener(string));
 170     }
 171
 172     /**
 173      * Produce a JSONArray of JSONObjects from a comma delimited text string
 174      * using a supplied JSONArray as the source of element names.
 175      * @param names A JSONArray of strings.
 176      * @param x A JSONTokener of the source text.
 177      * @return A JSONArray of JSONObjects.
 178      * @throws JSONException
 179      */
 180     public static JSONArray toJSONArray(JSONArray names, JSONTokener x)
 181         throws JSONException {
 182         if (names == null || names.length() == 0) {
 183             return null;
 184         }
 185         JSONArray ja = new JSONArray();
 186         for (;;) {
 187             JSONObject jo = rowToJSONObject(names, x);
 188             if (jo == null) {
 189                 break;
 190             }
 191             ja.put(jo);
 192         }
 193         if (ja.length() == 0) {
 194             return null;
 195         }
 196         return ja;
 197     }
 198
 199
 200     /**
 201      * Produce a comma delimited text row from a JSONArray. Values containing
 202      * the comma character will be quoted. Troublesome characters may be
 203      * removed.
 204      * @param ja A JSONArray of strings.
 205      * @return A string ending in NEWLINE.
 206      */
 207     public static String rowToString(JSONArray ja) {
 208         StringBuffer sb = new StringBuffer();
 209         for (int i = 0; i < ja.length(); i += 1) {
 210             if (i > 0) {
 211                 sb.append(',');
 212             }
 213             Object o = ja.opt(i);
 214             if (o != null) {
 215                 String s = o.toString();
 216                 if (s.length() > 0 && (s.indexOf(',') >= 0 || s.indexOf('\n') >= 0 ||
 217                                        s.indexOf('\r') >= 0 || s.indexOf(0) >= 0 ||
 218                                        s.charAt(0) == '"')) {
 219                     sb.append('"');
 220                     int length = s.length();
 221                     for (int j = 0; j < length; j += 1) {
 222                         char c = s.charAt(j);
 223                         if (c >= ' ' && c != '"') {
 224                             sb.append(c);
 225                         }
 226                     }
 227                     sb.append('"');
 228                 } else {
 229                     sb.append(s);
 230                 }
 231             }
 232         }
 233         sb.append('\n');
 234         return sb.toString();
 235     }
 236
 237     /**
 238      * Produce a comma delimited text from a JSONArray of JSONObjects. The
 239      * first row will be a list of names obtained by inspecting the first
 240      * JSONObject.
 241      * @param ja A JSONArray of JSONObjects.
 242      * @return A comma delimited text.
 243      * @throws JSONException
 244      */
 245     public static String toString(JSONArray ja) throws JSONException {
 246         JSONObject jo = ja.optJSONObject(0);
 247         if (jo != null) {
 248             JSONArray names = jo.names();
 249             if (names != null) {
 250                 return rowToString(names) + toString(names, ja);
 251             }
 252         }
 253         return null;
 254     }
 255
 256     /**
 257      * Produce a comma delimited text from a JSONArray of JSONObjects using
 258      * a provided list of names. The list of names is not included in the
 259      * output.
 260      * @param names A JSONArray of strings.
 261      * @param ja A JSONArray of JSONObjects.
 262      * @return A comma delimited text.
 263      * @throws JSONException
 264      */
 265     public static String toString(JSONArray names, JSONArray ja)
 266         throws JSONException {
 267         if (names == null || names.length() == 0) {
 268             return null;
 269         }
 270         StringBuffer sb = new StringBuffer();
 271         for (int i = 0; i < ja.length(); i += 1) {
 272             JSONObject jo = ja.optJSONObject(i);
 273             if (jo != null) {
 274                 sb.append(rowToString(jo.toJSONArray(names)));
 275             }
 276         }
 277         return sb.toString();
 278     }
 279 }