+ * Each row of text represents a row in a table or a data record. Each row + * ends with a NEWLINE character. Each row contains one or more values. + * Values are separated by commas. A value can contain any character except + * for comma, unless is is wrapped in single quotes or double quotes. + *
+ * The first row usually contains the names of the columns. + *
+ * A comma delimited list can be converted into a JSONArray of JSONObjects. + * The names for the elements in the JSONObjects can be taken from the names + * in the first row. + * @author JSON.org + * @version 2016-05-01 + */ +public class CDL { + + /** + * Get the next value. The value can be wrapped in quotes. The value can + * be empty. + * @param x A JSONTokener of the source text. + * @return The value string, or null if empty. + * @throws JSONException if the quoted string is badly formed. + */ + private static String getValue(JSONTokener x) throws JSONException { + char c; + char q; + StringBuffer sb; + do { + c = x.next(); + } while (c == ' ' || c == '\t'); + switch (c) { + case 0: + return null; + case '"': + case '\'': + q = c; + sb = new StringBuffer(); + for (;;) { + c = x.next(); + if (c == q) { + //Handle escaped double-quote + char nextC = x.next(); + if(nextC != '\"') { + // if our quote was the end of the file, don't step + if(nextC > 0) { + x.back(); + } + break; + } + } + if (c == 0 || c == '\n' || c == '\r') { + throw x.syntaxError("Missing close quote '" + q + "'."); + } + sb.append(c); + } + return sb.toString(); + case ',': + x.back(); + return ""; + default: + x.back(); + return x.nextTo(','); + } + } + + /** + * Produce a JSONArray of strings from a row of comma delimited values. + * @param x A JSONTokener of the source text. + * @return A JSONArray of strings. + * @throws JSONException + */ + public static JSONArray rowToJSONArray(JSONTokener x) throws JSONException { + JSONArray ja = new JSONArray(); + for (;;) { + String value = getValue(x); + char c = x.next(); + if (value == null || + (ja.length() == 0 && value.length() == 0 && c != ',')) { + return null; + } + ja.put(value); + for (;;) { + if (c == ',') { + break; + } + if (c != ' ') { + if (c == '\n' || c == '\r' || c == 0) { + return ja; + } + throw x.syntaxError("Bad character '" + c + "' (" + + (int)c + ")."); + } + c = x.next(); + } + } + } + + /** + * Produce a JSONObject from a row of comma delimited text, using a + * parallel JSONArray of strings to provides the names of the elements. + * @param names A JSONArray of names. This is commonly obtained from the + * first row of a comma delimited text file using the rowToJSONArray + * method. + * @param x A JSONTokener of the source text. + * @return A JSONObject combining the names and values. + * @throws JSONException + */ + public static JSONObject rowToJSONObject(JSONArray names, JSONTokener x) + throws JSONException { + JSONArray ja = rowToJSONArray(x); + return ja != null ? ja.toJSONObject(names) : null; + } + + /** + * Produce a comma delimited text row from a JSONArray. Values containing + * the comma character will be quoted. Troublesome characters may be + * removed. + * @param ja A JSONArray of strings. + * @return A string ending in NEWLINE. + */ + public static String rowToString(JSONArray ja) { + StringBuilder sb = new StringBuilder(); + for (int i = 0; i < ja.length(); i += 1) { + if (i > 0) { + sb.append(','); + } + Object object = ja.opt(i); + if (object != null) { + String string = object.toString(); + if (string.length() > 0 && (string.indexOf(',') >= 0 || + string.indexOf('\n') >= 0 || string.indexOf('\r') >= 0 || + string.indexOf(0) >= 0 || string.charAt(0) == '"')) { + sb.append('"'); + int length = string.length(); + for (int j = 0; j < length; j += 1) { + char c = string.charAt(j); + if (c >= ' ' && c != '"') { + sb.append(c); + } + } + sb.append('"'); + } else { + sb.append(string); + } + } + } + sb.append('\n'); + return sb.toString(); + } + + /** + * Produce a JSONArray of JSONObjects from a comma delimited text string, + * using the first row as a source of names. + * @param string The comma delimited text. + * @return A JSONArray of JSONObjects. + * @throws JSONException + */ + public static JSONArray toJSONArray(String string) throws JSONException { + return toJSONArray(new JSONTokener(string)); + } + + /** + * Produce a JSONArray of JSONObjects from a comma delimited text string, + * using the first row as a source of names. + * @param x The JSONTokener containing the comma delimited text. + * @return A JSONArray of JSONObjects. + * @throws JSONException + */ + public static JSONArray toJSONArray(JSONTokener x) throws JSONException { + return toJSONArray(rowToJSONArray(x), x); + } + + /** + * Produce a JSONArray of JSONObjects from a comma delimited text string + * using a supplied JSONArray as the source of element names. + * @param names A JSONArray of strings. + * @param string The comma delimited text. + * @return A JSONArray of JSONObjects. + * @throws JSONException + */ + public static JSONArray toJSONArray(JSONArray names, String string) + throws JSONException { + return toJSONArray(names, new JSONTokener(string)); + } + + /** + * Produce a JSONArray of JSONObjects from a comma delimited text string + * using a supplied JSONArray as the source of element names. + * @param names A JSONArray of strings. + * @param x A JSONTokener of the source text. + * @return A JSONArray of JSONObjects. + * @throws JSONException + */ + public static JSONArray toJSONArray(JSONArray names, JSONTokener x) + throws JSONException { + if (names == null || names.length() == 0) { + return null; + } + JSONArray ja = new JSONArray(); + for (;;) { + JSONObject jo = rowToJSONObject(names, x); + if (jo == null) { + break; + } + ja.put(jo); + } + if (ja.length() == 0) { + return null; + } + return ja; + } + + + /** + * Produce a comma delimited text from a JSONArray of JSONObjects. The + * first row will be a list of names obtained by inspecting the first + * JSONObject. + * @param ja A JSONArray of JSONObjects. + * @return A comma delimited text. + * @throws JSONException + */ + public static String toString(JSONArray ja) throws JSONException { + JSONObject jo = ja.optJSONObject(0); + if (jo != null) { + JSONArray names = jo.names(); + if (names != null) { + return rowToString(names) + toString(names, ja); + } + } + return null; + } + + /** + * Produce a comma delimited text from a JSONArray of JSONObjects using + * a provided list of names. The list of names is not included in the + * output. + * @param names A JSONArray of strings. + * @param ja A JSONArray of JSONObjects. + * @return A comma delimited text. + * @throws JSONException + */ + public static String toString(JSONArray names, JSONArray ja) + throws JSONException { + if (names == null || names.length() == 0) { + return null; + } + StringBuffer sb = new StringBuffer(); + for (int i = 0; i < ja.length(); i += 1) { + JSONObject jo = ja.optJSONObject(i); + if (jo != null) { + sb.append(rowToString(jo.toJSONArray(names))); + } + } + return sb.toString(); + } +}