Add 'getNumBits' to Result objects to return when not all bits of the raw byte representation are valid (#664)

core/src/main/java/com/google/zxing/Result.java

@@ -28,6 +28,7 @@ public final class Result {
 
   private final String text;
   private final byte[] rawBytes;
+  private final int numBits;
   private ResultPoint[] resultPoints;
   private final BarcodeFormat format;
   private Map<ResultMetadataType,Object> resultMetadata;
@@ -45,8 +46,19 @@ public final class Result {
                 ResultPoint[] resultPoints,
                 BarcodeFormat format,
                 long timestamp) {
+    this(text, rawBytes, rawBytes == null ? 0 : 8 * rawBytes.length,
+         resultPoints, format, timestamp);
+  }
+
+  public Result(String text,
+                byte[] rawBytes,
+                int numBits,
+                ResultPoint[] resultPoints,
+                BarcodeFormat format,
+                long timestamp) {
     this.text = text;
     this.rawBytes = rawBytes;
+    this.numBits = numBits;
     this.resultPoints = resultPoints;
     this.format = format;
     this.resultMetadata = null;
@@ -67,6 +79,14 @@ public final class Result {
     return rawBytes;
   }
 
+  /**
+   * @return how many bits of {@link #getRawBytes()} are valid; typically 8 times its length
+   * @since 3.3.0
+   */
+  public int getNumBits() {
+    return numBits;
+  }
+
   /**
    * @return points related to the barcode in the image. These are typically points
    *         identifying finder patterns or the corners of the barcode. The exact meaning is

core/src/main/java/com/google/zxing/aztec/AztecReader.java

@@ -95,7 +95,12 @@ public final class AztecReader implements Reader {
       }
     }
 
-    Result result = new Result(decoderResult.getText(), decoderResult.getRawBytes(), points, BarcodeFormat.AZTEC);
+    Result result = new Result(decoderResult.getText(),
+                               decoderResult.getRawBytes(),
+                               decoderResult.getNumBits(),
+                               points,
+                               BarcodeFormat.AZTEC,
+                               System.currentTimeMillis());
     
     List<byte[]> byteSegments = decoderResult.getByteSegments();
     if (byteSegments != null) {

core/src/main/java/com/google/zxing/aztec/decoder/Decoder.java

@@ -77,7 +77,9 @@ public final class Decoder {
     boolean[] correctedBits = correctBits(rawbits);
     byte[] rawBytes = convertBoolArrayToByteArray(correctedBits);
     String result = getEncodedData(correctedBits);
-    return new DecoderResult(rawBytes, result, null, null);
+    DecoderResult decoderResult = new DecoderResult(rawBytes, result, null, null);
+    decoderResult.setNumBits(correctedBits.length);
+    return decoderResult;
   }
 
   // This method is used for testing the high-level encoder

core/src/main/java/com/google/zxing/common/DecoderResult.java

@@ -28,6 +28,7 @@ import java.util.List;
 public final class DecoderResult {
 
   private final byte[] rawBytes;
+  private int numBits;
   private final String text;
   private final List<byte[]> byteSegments;
   private final String ecLevel;
@@ -51,6 +52,7 @@ public final class DecoderResult {
                        int saSequence,
                        int saParity) {
     this.rawBytes = rawBytes;
+    this.numBits = rawBytes == null ? 0 : 8 * rawBytes.length;
     this.text = text;
     this.byteSegments = byteSegments;
     this.ecLevel = ecLevel;
@@ -58,22 +60,53 @@ public final class DecoderResult {
     this.structuredAppendSequenceNumber = saSequence;
   }
 
+  /**
+   * @return raw bytes representing the result, or {@code null} if not applicable
+   */
   public byte[] getRawBytes() {
     return rawBytes;
   }
 
+  /**
+   * @return how many bits of {@link #getRawBytes()} are valid; typically 8 times its length
+   * @since 3.3.0
+   */
+  public int getNumBits() {
+    return numBits;
+  }
+
+  /**
+   * @param numBits overrides the number of bits that are valid in {@link #getRawBytes()}
+   * @since 3.3.0
+   */
+  public void setNumBits(int numBits) {
+    this.numBits = numBits;
+  }
+
+  /**
+   * @return text representation of the result
+   */
   public String getText() {
     return text;
   }
 
+  /**
+   * @return list of byte segments in the result, or {@code null} if not applicable
+   */
   public List<byte[]> getByteSegments() {
     return byteSegments;
   }
 
+  /**
+   * @return name of error correction level used, or {@code null} if not applicable
+   */
   public String getECLevel() {
     return ecLevel;
   }
 
+  /**
+   * @return number of errors corrected, or {@code null} if not applicable
+   */
   public Integer getErrorsCorrected() {
     return errorsCorrected;
   }
@@ -82,6 +115,9 @@ public final class DecoderResult {
     this.errorsCorrected = errorsCorrected;
   }
 
+  /**
+   * @return number of erasures corrected, or {@code null} if not applicable
+   */
   public Integer getErasures() {
     return erasures;
   }
@@ -90,6 +126,9 @@ public final class DecoderResult {
     this.erasures = erasures;
   }
 
+  /**
+   * @return arbitrary additional metadata
+   */
   public Object getOther() {
     return other;
   }

core/src/main/java/com/google/zxing/multi/GenericMultipleBarcodeReader.java

@@ -167,7 +167,12 @@ public final class GenericMultipleBarcodeReader implements MultipleBarcodeReader
         newResultPoints[i] = new ResultPoint(oldPoint.getX() + xOffset, oldPoint.getY() + yOffset);
       }
     }
-    Result newResult = new Result(result.getText(), result.getRawBytes(), newResultPoints, result.getBarcodeFormat());
+    Result newResult = new Result(result.getText(),
+                                  result.getRawBytes(),
+                                  result.getNumBits(),
+                                  newResultPoints,
+                                  result.getBarcodeFormat(),
+                                  result.getTimestamp());
     newResult.putAllMetadata(result.getResultMetadata());
     return newResult;
   }

core/src/test/java/com/google/zxing/aztec/decoder/DecoderTest.java

@@ -19,6 +19,7 @@ import com.google.zxing.FormatException;
 import com.google.zxing.ResultPoint;
 import com.google.zxing.aztec.AztecDetectorResult;
 import com.google.zxing.common.BitMatrix;
+import com.google.zxing.common.DecoderResult;
 import org.junit.Test;
 import org.junit.Assert;
 
@@ -26,6 +27,44 @@ public final class DecoderTest extends Assert {
 
   private static final ResultPoint[] NO_POINTS = new ResultPoint[0];
   
+  @Test
+  public void testAztecResult() throws FormatException {
+    BitMatrix matrix = BitMatrix.parse(
+        "X X X X X     X X X       X X X     X X X     \n" +
+        "X X X     X X X     X X X X     X X X     X X \n" +
+        "  X   X X       X   X   X X X X     X     X X \n" +
+        "  X   X X     X X     X     X   X       X   X \n" +
+        "  X X   X X         X               X X     X \n" +
+        "  X X   X X X X X X X X X X X X X X X     X   \n" +
+        "  X X X X X                       X   X X X   \n" +
+        "  X   X   X   X X X X X X X X X   X X X   X X \n" +
+        "  X   X X X   X               X   X X       X \n" +
+        "  X X   X X   X   X X X X X   X   X X X X   X \n" +
+        "  X X   X X   X   X       X   X   X   X X X   \n" +
+        "  X   X   X   X   X   X   X   X   X   X   X   \n" +
+        "  X X X   X   X   X       X   X   X X   X X   \n" +
+        "  X X X X X   X   X X X X X   X   X X X   X X \n" +
+        "X X   X X X   X               X   X   X X   X \n" +
+        "  X       X   X X X X X X X X X   X   X     X \n" +
+        "  X X   X X                       X X   X X   \n" +
+        "  X X X   X X X X X X X X X X X X X X   X X   \n" +
+        "X     X     X     X X   X X               X X \n" +
+        "X   X X X X X   X X X X X     X   X   X     X \n" +
+        "X X X   X X X X           X X X       X     X \n" +
+        "X X     X X X     X X X X     X X X     X X   \n" +
+        "    X X X     X X X       X X X     X X X X   \n",
+        "X ", "  ");
+    AztecDetectorResult r = new AztecDetectorResult(matrix, NO_POINTS, false, 30, 2);
+    DecoderResult result = new Decoder().decode(r);
+    assertEquals("88888TTTTTTTTTTTTTTTTTTTTTTTTTTTTTT", result.getText());
+    assertArrayEquals(
+        new byte[] {-11, 85, 85, 117, 107, 90, -42, -75, -83, 107,
+            90, -42, -75, -83, 107, 90, -42, -75, -83, 107,
+            90, -42, -80},
+        result.getRawBytes());
+    assertEquals(180, result.getNumBits());
+  }
+
   /**
    * throws
    * <pre>com.google.zxing.FormatException: com.google.zxing.common.reedsolomon.ReedSolomonException: Error locator degree does not match number of roots