Github user markap14 commented on a diff in the pull request:

    https://github.com/apache/nifi/pull/1214#discussion_r102947724
  
    --- Diff: 
nifi-commons/nifi-utils/src/main/java/org/apache/nifi/stream/io/util/TextLineDemarcator.java
 ---
    @@ -90,58 +70,73 @@ public OffsetInfo nextOffsetInfo() {
          * by either '\r', '\n' or '\r\n'). <br>
          * The <i>offset info</i> computed and returned as {@link OffsetInfo} 
where
          * {@link OffsetInfo#isStartsWithMatch()} will return true if
    -     * <code>startsWith</code> was successfully matched with the stsarting 
bytes
    +     * <code>startsWith</code> was successfully matched with the starting 
bytes
          * of the text line.
          *
    +     * NOTE: The reason for 2 'nextOffsetInfo(..)' operations is that the
    +     * 'startsWith' argument will force the actual token to be extracted 
and
    +     * then matched introducing the overhead for System.arrayCopy and 
matching
    +     * logic which is an optional scenario and is avoided all together if
    +     * 'startsWith' is not provided (i.e., null).
    +     *
          * @return offset info
          */
    -    public OffsetInfo nextOffsetInfo(byte[] startsWith) {
    +    public OffsetInfo nextOffsetInfo(byte[] startsWith) throws IOException 
{
             OffsetInfo offsetInfo = null;
    -        int lineLength = 0;
    -        byte[] token = null;
    -        lineLoop:
    -        while (this.bufferLength != -1) {
    -            if (this.index >= this.bufferLength) {
    +        byte previousByteVal = 0;
    +        byte[] data = null;
    +        nextTokenLoop:
    +        while (data == null && this.availableBytesLength != -1) {
    +            if (this.index >= this.availableBytesLength) {
                     this.fill();
                 }
    -            if (this.bufferLength != -1) {
    -                int i;
    +            int delimiterSize = 0;
    +            if (this.availableBytesLength != -1) {
                     byte byteVal;
    -                for (i = this.index; i < this.bufferLength; i++) {
    +                int i;
    +                for (i = this.index; i < this.availableBytesLength; i++) {
                         byteVal = this.buffer[i];
    -                    lineLength++;
    -                    int crlfLength = computeEol(byteVal, i + 1);
    -                    if (crlfLength > 0) {
    -                        i += crlfLength;
    -                        if (crlfLength == 2) {
    -                            lineLength++;
    -                        }
    -                        offsetInfo = new OffsetInfo(this.offset, 
lineLength, crlfLength);
    +
    +                    if (byteVal == LF) {
    +                        delimiterSize = previousByteVal == CR ? 2 : 1;
    +                    } else if (previousByteVal == CR) {
    +                        delimiterSize = 1;
    +                        i--;
    +                    }
    +                    previousByteVal = byteVal;
    +                    if (delimiterSize > 0) {
    +                        this.index = i + 1;
    +                        int size = Math.max(1, this.index - this.mark);
    +                        offsetInfo = new OffsetInfo(this.offset, size, 
delimiterSize);
    +                        this.offset += size;
                             if (startsWith != null) {
    -                            token = this.extractDataToken(lineLength);
    +                            data = this.extractDataToken(size);
                             }
                             this.mark = this.index;
    -                        break lineLoop;
    +                        break nextTokenLoop;
                         }
                     }
                     this.index = i;
    +            } else {
    +                delimiterSize = previousByteVal == CR || previousByteVal 
== LF ? 1 : 0;
    +                if (offsetInfo == null) {
    +                    int size = this.index - this.mark;
    +                    if (size > 0) {
    +                        offsetInfo = new OffsetInfo(this.offset, size, 
delimiterSize);
    +                        this.offset += size;
    +                    }
    +                }
    +                if (startsWith != null) {
    +                    data = this.extractDataToken(this.index - this.mark);
    +                }
                 }
             }
    -        // EOF where last char(s) are not CRLF.
    -        if (lineLength > 0 && offsetInfo == null) {
    -            offsetInfo = new OffsetInfo(this.offset, lineLength, 0);
    -            if (startsWith != null) {
    -                token = this.extractDataToken(lineLength);
    -            }
    -        }
    -        this.offset += lineLength;
     
    -        // checks if the new line starts with 'startsWith' chars
    -        if (startsWith != null) {
    +        if (startsWith != null && data != null) {
                 for (int i = 0; i < startsWith.length; i++) {
                     byte sB = startsWith[i];
    -                if (token != null && sB != token[i]) {
    -                    offsetInfo.setStartsWithMatch(0);
    +                if (sB != data[i]) {
    --- End diff --
    
    There is a potential `ArrayIndexOutOfBoundsException` here. If `startsWith` 
is longer than the last token that is extracted and the token does match the 
first `data.length` bytes of the `startsWith` array, then it will throw an 
`ArrayIndexOutOfBoundsException`. The following unit test will expose that:
    
    
    ```
    @Test
        public void testStartsWithLongerThanLastToken() throws IOException {
            final byte[] inputData = "This is going to be a spectacular 
test\nThis is".getBytes(StandardCharsets.UTF_8);
            final byte[] startsWith = "This is going to 
be".getBytes(StandardCharsets.UTF_8);
    
            try (final InputStream is = new ByteArrayInputStream(inputData);
                final TextLineDemarcator demarcator = new 
TextLineDemarcator(is)) {
    
                final OffsetInfo first = demarcator.nextOffsetInfo(startsWith);
                assertNotNull(first);
                assertEquals(0, first.getStartOffset());
                assertEquals(39, first.getLength());
                assertEquals(1, first.getCrlfLength());
                assertTrue(first.isStartsWithMatch());
    
                final OffsetInfo second = demarcator.nextOffsetInfo(startsWith);
                assertNotNull(second);
                assertEquals(39, second.getStartOffset());
                assertEquals(7, second.getLength());
                assertEquals(0, second.getCrlfLength());
                assertFalse(second.isStartsWithMatch());
            }
        }
    
    ```


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---

Reply via email to