Updated Java code - changed QrSegmentAdvanced.makeSegmentsOptimally() to throw DataTooLongException and synchronize logic and Javadoc with QrCode class, changed Javadoc of DataTooLongException.

java/io/nayuki/qrcodegen/DataTooLongException.java

@@ -28,9 +28,10 @@ package io.nayuki.qrcodegen;
  * Thrown when the supplied data does not fit any QR Code version. Ways to handle this exception include:
  * <ul>
  *   <li><p>Decrease the error correction level if it was greater than {@code Ecc.LOW}.</p></li>
- *   <li><p>If the advanced {@code encodeSegments()} function with 6 arguments was called, then increase the
- *     maxVersion argument if it was less than {@link QrCode#MAX_VERSION}. (This advice does not apply to the
- *     other factory functions because they search all versions up to {@code QrCode.MAX_VERSION}.)</p></li>
+ *   <li><p>If the advanced {@code encodeSegments()} function with 6 arguments or the
+ *     {@code makeSegmentsOptimally()} function was called, then increase the maxVersion argument
+ *     if it was less than {@link QrCode#MAX_VERSION}. (This advice does not apply to the other
+ *     factory functions because they search all versions up to {@code QrCode.MAX_VERSION}.)</p></li>
  *   <li><p>Split the text data into better or optimal segments in order to reduce the number of
  *     bits required. (See {@link QrSegmentAdvanced#makeSegmentsOptimally(String,QrCode.Ecc,int,int)
  *     QrSegmentAdvanced.makeSegmentsOptimally()}.)</p></li>
@@ -42,6 +43,7 @@ package io.nayuki.qrcodegen;
  * @see QrCode#encodeBinary(byte[], QrCode.Ecc)
  * @see QrCode#encodeSegments(java.util.List, QrCode.Ecc)
  * @see QrCode#encodeSegments(java.util.List, QrCode.Ecc, int, int, int, boolean)
+ * @see QrSegmentAdvanced#makeSegmentsOptimally(String, io.nayuki.qrcodegen.QrCode.Ecc, int, int)
  */
 public class DataTooLongException extends IllegalArgumentException {
 	

java/io/nayuki/qrcodegen/QrSegmentAdvanced.java

@@ -57,8 +57,8 @@ public final class QrSegmentAdvanced {
 	 * @return a new mutable list (not {@code null}) of segments (not {@code null})
 	 * containing the text, minimizing the bit length with respect to the constraints
 	 * @throws NullPointerException if the text or error correction level is {@code null}
-	 * @throws IllegalArgumentException if 1 ≤ minVersion ≤ maxVersion ≤ 40
-	 * is violated, or if the data is too long to fit in a QR Code at maxVersion at ECL
+	 * @throws IllegalArgumentException if 1 ≤ minVersion ≤ maxVersion ≤ 40 is violated
+	 * @throws DataTooLongException if the text fails to fit in the maxVersion QR Code at the ECL
 	 */
 	public static List<QrSegment> makeSegmentsOptimally(String text, QrCode.Ecc ecl, int minVersion, int maxVersion) {
 		// Check arguments
@@ -70,7 +70,7 @@ public final class QrSegmentAdvanced {
 		// Iterate through version numbers, and make tentative segments
 		List<QrSegment> segs = null;
 		int[] codePoints = toCodePoints(text);
-		for (int version = minVersion; version <= maxVersion; version++) {
+		for (int version = minVersion; ; version++) {
 			if (version == minVersion || version == 10 || version == 27)
 				segs = makeSegmentsOptimally(codePoints, version);
 			assert segs != null;
@@ -79,9 +79,14 @@ public final class QrSegmentAdvanced {
 			int dataCapacityBits = QrCode.getNumDataCodewords(version, ecl) * 8;
 			int dataUsedBits = QrSegment.getTotalBits(segs, version);
 			if (dataUsedBits != -1 && dataUsedBits <= dataCapacityBits)
-				return segs;
+				return segs;  // This version number is found to be suitable
+			if (version >= maxVersion) {  // All versions in the range could not fit the given text
+				String msg = "Segment too long";
+				if (dataUsedBits != -1)
+					msg = String.format("Data length = %d bits, Max capacity = %d bits", dataUsedBits, dataCapacityBits);
+				throw new DataTooLongException(msg);
+			}
 		}
-		throw new IllegalArgumentException("Data too long");
 	}