You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@hbase.apache.org by mi...@apache.org on 2016/02/04 18:31:30 UTC
[10/23] hbase-site git commit: Published site at
2cf8af5bf1d501156cbb3b421cf75c1051ead7d9.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/32672884/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/HFileBlock.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/HFileBlock.html b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/HFileBlock.html
index 745e703..1587e5e 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/HFileBlock.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/HFileBlock.html
@@ -1361,609 +1361,610 @@
<span class="sourceLineNo">1353</span> /** The filesystem used to access data */<a name="line.1353"></a>
<span class="sourceLineNo">1354</span> protected HFileSystem hfs;<a name="line.1354"></a>
<span class="sourceLineNo">1355</span><a name="line.1355"></a>
-<span class="sourceLineNo">1356</span> /** The path (if any) where this data is coming from */<a name="line.1356"></a>
-<span class="sourceLineNo">1357</span> protected Path path;<a name="line.1357"></a>
-<span class="sourceLineNo">1358</span><a name="line.1358"></a>
-<span class="sourceLineNo">1359</span> private final Lock streamLock = new ReentrantLock();<a name="line.1359"></a>
+<span class="sourceLineNo">1356</span> private final Lock streamLock = new ReentrantLock();<a name="line.1356"></a>
+<span class="sourceLineNo">1357</span><a name="line.1357"></a>
+<span class="sourceLineNo">1358</span> /** The default buffer size for our buffered streams */<a name="line.1358"></a>
+<span class="sourceLineNo">1359</span> public static final int DEFAULT_BUFFER_SIZE = 1 << 20;<a name="line.1359"></a>
<span class="sourceLineNo">1360</span><a name="line.1360"></a>
-<span class="sourceLineNo">1361</span> /** The default buffer size for our buffered streams */<a name="line.1361"></a>
-<span class="sourceLineNo">1362</span> public static final int DEFAULT_BUFFER_SIZE = 1 << 20;<a name="line.1362"></a>
-<span class="sourceLineNo">1363</span><a name="line.1363"></a>
-<span class="sourceLineNo">1364</span> protected HFileContext fileContext;<a name="line.1364"></a>
-<span class="sourceLineNo">1365</span><a name="line.1365"></a>
-<span class="sourceLineNo">1366</span> public FSReaderImpl(FSDataInputStreamWrapper stream, long fileSize, HFileSystem hfs, Path path,<a name="line.1366"></a>
-<span class="sourceLineNo">1367</span> HFileContext fileContext) throws IOException {<a name="line.1367"></a>
-<span class="sourceLineNo">1368</span> this.fileSize = fileSize;<a name="line.1368"></a>
-<span class="sourceLineNo">1369</span> this.hfs = hfs;<a name="line.1369"></a>
-<span class="sourceLineNo">1370</span> this.path = path;<a name="line.1370"></a>
-<span class="sourceLineNo">1371</span> this.fileContext = fileContext;<a name="line.1371"></a>
-<span class="sourceLineNo">1372</span> this.hdrSize = headerSize(fileContext.isUseHBaseChecksum());<a name="line.1372"></a>
-<span class="sourceLineNo">1373</span><a name="line.1373"></a>
-<span class="sourceLineNo">1374</span> this.streamWrapper = stream;<a name="line.1374"></a>
-<span class="sourceLineNo">1375</span> // Older versions of HBase didn't support checksum.<a name="line.1375"></a>
-<span class="sourceLineNo">1376</span> this.streamWrapper.prepareForBlockReader(!fileContext.isUseHBaseChecksum());<a name="line.1376"></a>
-<span class="sourceLineNo">1377</span> defaultDecodingCtx = new HFileBlockDefaultDecodingContext(fileContext);<a name="line.1377"></a>
-<span class="sourceLineNo">1378</span> encodedBlockDecodingCtx = defaultDecodingCtx;<a name="line.1378"></a>
-<span class="sourceLineNo">1379</span> }<a name="line.1379"></a>
-<span class="sourceLineNo">1380</span><a name="line.1380"></a>
-<span class="sourceLineNo">1381</span> /**<a name="line.1381"></a>
-<span class="sourceLineNo">1382</span> * A constructor that reads files with the latest minor version.<a name="line.1382"></a>
-<span class="sourceLineNo">1383</span> * This is used by unit tests only.<a name="line.1383"></a>
-<span class="sourceLineNo">1384</span> */<a name="line.1384"></a>
-<span class="sourceLineNo">1385</span> FSReaderImpl(FSDataInputStream istream, long fileSize, HFileContext fileContext)<a name="line.1385"></a>
-<span class="sourceLineNo">1386</span> throws IOException {<a name="line.1386"></a>
-<span class="sourceLineNo">1387</span> this(new FSDataInputStreamWrapper(istream), fileSize, null, null, fileContext);<a name="line.1387"></a>
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-<span class="sourceLineNo">1391</span> final FSReader owner = this; // handle for inner class<a name="line.1391"></a>
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-<span class="sourceLineNo">1393</span> private long offset = startOffset;<a name="line.1393"></a>
-<span class="sourceLineNo">1394</span><a name="line.1394"></a>
-<span class="sourceLineNo">1395</span> @Override<a name="line.1395"></a>
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-<span class="sourceLineNo">1401</span> return b.unpack(fileContext, owner);<a name="line.1401"></a>
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-<span class="sourceLineNo">1409</span> throw new IOException("Expected block of type " + blockType<a name="line.1409"></a>
-<span class="sourceLineNo">1410</span> + " but found " + blk.getBlockType());<a name="line.1410"></a>
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-<span class="sourceLineNo">1417</span> /**<a name="line.1417"></a>
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-<span class="sourceLineNo">1419</span> * the on-disk size of the next block, or -1 if it could not be determined.<a name="line.1419"></a>
-<span class="sourceLineNo">1420</span> *<a name="line.1420"></a>
-<span class="sourceLineNo">1421</span> * @param dest destination buffer<a name="line.1421"></a>
-<span class="sourceLineNo">1422</span> * @param destOffset offset in the destination buffer<a name="line.1422"></a>
-<span class="sourceLineNo">1423</span> * @param size size of the block to be read<a name="line.1423"></a>
-<span class="sourceLineNo">1424</span> * @param peekIntoNextBlock whether to read the next block's on-disk size<a name="line.1424"></a>
-<span class="sourceLineNo">1425</span> * @param fileOffset position in the stream to read at<a name="line.1425"></a>
-<span class="sourceLineNo">1426</span> * @param pread whether we should do a positional read<a name="line.1426"></a>
-<span class="sourceLineNo">1427</span> * @param istream The input source of data<a name="line.1427"></a>
-<span class="sourceLineNo">1428</span> * @return the on-disk size of the next block with header size included, or<a name="line.1428"></a>
-<span class="sourceLineNo">1429</span> * -1 if it could not be determined<a name="line.1429"></a>
-<span class="sourceLineNo">1430</span> * @throws IOException<a name="line.1430"></a>
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-<span class="sourceLineNo">1434</span> boolean peekIntoNextBlock, long fileOffset, boolean pread)<a name="line.1434"></a>
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-<span class="sourceLineNo">1436</span> if (peekIntoNextBlock &&<a name="line.1436"></a>
-<span class="sourceLineNo">1437</span> destOffset + size + hdrSize > dest.length) {<a name="line.1437"></a>
-<span class="sourceLineNo">1438</span> // We are asked to read the next block's header as well, but there is<a name="line.1438"></a>
-<span class="sourceLineNo">1439</span> // not enough room in the array.<a name="line.1439"></a>
-<span class="sourceLineNo">1440</span> throw new IOException("Attempted to read " + size + " bytes and " +<a name="line.1440"></a>
-<span class="sourceLineNo">1441</span> hdrSize + " bytes of next header into a " + dest.length +<a name="line.1441"></a>
-<span class="sourceLineNo">1442</span> "-byte array at offset " + destOffset);<a name="line.1442"></a>
-<span class="sourceLineNo">1443</span> }<a name="line.1443"></a>
-<span class="sourceLineNo">1444</span><a name="line.1444"></a>
-<span class="sourceLineNo">1445</span> if (!pread && streamLock.tryLock()) {<a name="line.1445"></a>
-<span class="sourceLineNo">1446</span> // Seek + read. Better for scanning.<a name="line.1446"></a>
-<span class="sourceLineNo">1447</span> try {<a name="line.1447"></a>
-<span class="sourceLineNo">1448</span> istream.seek(fileOffset);<a name="line.1448"></a>
-<span class="sourceLineNo">1449</span><a name="line.1449"></a>
-<span class="sourceLineNo">1450</span> long realOffset = istream.getPos();<a name="line.1450"></a>
-<span class="sourceLineNo">1451</span> if (realOffset != fileOffset) {<a name="line.1451"></a>
-<span class="sourceLineNo">1452</span> throw new IOException("Tried to seek to " + fileOffset + " to "<a name="line.1452"></a>
-<span class="sourceLineNo">1453</span> + "read " + size + " bytes, but pos=" + realOffset<a name="line.1453"></a>
-<span class="sourceLineNo">1454</span> + " after seek");<a name="line.1454"></a>
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-<span class="sourceLineNo">1456</span><a name="line.1456"></a>
-<span class="sourceLineNo">1457</span> if (!peekIntoNextBlock) {<a name="line.1457"></a>
-<span class="sourceLineNo">1458</span> IOUtils.readFully(istream, dest, destOffset, size);<a name="line.1458"></a>
-<span class="sourceLineNo">1459</span> return -1;<a name="line.1459"></a>
-<span class="sourceLineNo">1460</span> }<a name="line.1460"></a>
-<span class="sourceLineNo">1461</span><a name="line.1461"></a>
-<span class="sourceLineNo">1462</span> // Try to read the next block header.<a name="line.1462"></a>
-<span class="sourceLineNo">1463</span> if (!readWithExtra(istream, dest, destOffset, size, hdrSize))<a name="line.1463"></a>
-<span class="sourceLineNo">1464</span> return -1;<a name="line.1464"></a>
-<span class="sourceLineNo">1465</span> } finally {<a name="line.1465"></a>
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-<span class="sourceLineNo">1469</span> // Positional read. Better for random reads; or when the streamLock is already locked.<a name="line.1469"></a>
-<span class="sourceLineNo">1470</span> int extraSize = peekIntoNextBlock ? hdrSize : 0;<a name="line.1470"></a>
-<span class="sourceLineNo">1471</span> if (!positionalReadWithExtra(istream, fileOffset, dest, destOffset,<a name="line.1471"></a>
-<span class="sourceLineNo">1472</span> size, extraSize)) {<a name="line.1472"></a>
-<span class="sourceLineNo">1473</span> return -1;<a name="line.1473"></a>
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-<span class="sourceLineNo">1476</span><a name="line.1476"></a>
-<span class="sourceLineNo">1477</span> assert peekIntoNextBlock;<a name="line.1477"></a>
-<span class="sourceLineNo">1478</span> return Bytes.toInt(dest, destOffset + size + BlockType.MAGIC_LENGTH) + hdrSize;<a name="line.1478"></a>
-<span class="sourceLineNo">1479</span> }<a name="line.1479"></a>
-<span class="sourceLineNo">1480</span><a name="line.1480"></a>
-<span class="sourceLineNo">1481</span> /**<a name="line.1481"></a>
-<span class="sourceLineNo">1482</span> * Reads a version 2 block (version 1 blocks not supported and not expected). Tries to do as<a name="line.1482"></a>
-<span class="sourceLineNo">1483</span> * little memory allocation as possible, using the provided on-disk size.<a name="line.1483"></a>
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-<span class="sourceLineNo">1487</span> * the header, or -1 if unknown<a name="line.1487"></a>
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-<span class="sourceLineNo">1489</span> * expected to be -1. This parameter is only used in version 1.<a name="line.1489"></a>
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-<span class="sourceLineNo">1512</span> offset + " filesize " + fileSize +<a name="line.1512"></a>
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+<span class="sourceLineNo">1431</span> * @throws IOException<a name="line.1431"></a>
+<span class="sourceLineNo">1432</span> */<a name="line.1432"></a>
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+<span class="sourceLineNo">1434</span> byte[] dest, int destOffset, int size,<a name="line.1434"></a>
+<span class="sourceLineNo">1435</span> boolean peekIntoNextBlock, long fileOffset, boolean pread)<a name="line.1435"></a>
+<span class="sourceLineNo">1436</span> throws IOException {<a name="line.1436"></a>
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+<span class="sourceLineNo">1438</span> destOffset + size + hdrSize > dest.length) {<a name="line.1438"></a>
+<span class="sourceLineNo">1439</span> // We are asked to read the next block's header as well, but there is<a name="line.1439"></a>
+<span class="sourceLineNo">1440</span> // not enough room in the array.<a name="line.1440"></a>
+<span class="sourceLineNo">1441</span> throw new IOException("Attempted to read " + size + " bytes and " +<a name="line.1441"></a>
+<span class="sourceLineNo">1442</span> hdrSize + " bytes of next header into a " + dest.length +<a name="line.1442"></a>
+<span class="sourceLineNo">1443</span> "-byte array at offset " + destOffset);<a name="line.1443"></a>
+<span class="sourceLineNo">1444</span> }<a name="line.1444"></a>
+<span class="sourceLineNo">1445</span><a name="line.1445"></a>
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+<span class="sourceLineNo">1447</span> // Seek + read. Better for scanning.<a name="line.1447"></a>
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+<span class="sourceLineNo">1449</span> istream.seek(fileOffset);<a name="line.1449"></a>
+<span class="sourceLineNo">1450</span><a name="line.1450"></a>
+<span class="sourceLineNo">1451</span> long realOffset = istream.getPos();<a name="line.1451"></a>
+<span class="sourceLineNo">1452</span> if (realOffset != fileOffset) {<a name="line.1452"></a>
+<span class="sourceLineNo">1453</span> throw new IOException("Tried to seek to " + fileOffset + " to "<a name="line.1453"></a>
+<span class="sourceLineNo">1454</span> + "read " + size + " bytes, but pos=" + realOffset<a name="line.1454"></a>
+<span class="sourceLineNo">1455</span> + " after seek");<a name="line.1455"></a>
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+<span class="sourceLineNo">1457</span><a name="line.1457"></a>
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+<span class="sourceLineNo">1459</span> IOUtils.readFully(istream, dest, destOffset, size);<a name="line.1459"></a>
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+<span class="sourceLineNo">1462</span><a name="line.1462"></a>
+<span class="sourceLineNo">1463</span> // Try to read the next block header.<a name="line.1463"></a>
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+<span class="sourceLineNo">1465</span> return -1;<a name="line.1465"></a>
+<span class="sourceLineNo">1466</span> } finally {<a name="line.1466"></a>
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+<span class="sourceLineNo">1476</span> }<a name="line.1476"></a>
+<span class="sourceLineNo">1477</span><a name="line.1477"></a>
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+<span class="sourceLineNo">1481</span><a name="line.1481"></a>
+<span class="sourceLineNo">1482</span> /**<a name="line.1482"></a>
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+<span class="sourceLineNo">1485</span> *<a name="line.1485"></a>
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+<span class="sourceLineNo">1496</span> throws IOException {<a name="line.1496"></a>
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+<span class="sourceLineNo">1499</span> // hbase checksums or not for this read call. This is not<a name="line.1499"></a>
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+<span class="sourceLineNo">1502</span> // guaranteed to use hdfs checksum verification.<a name="line.1502"></a>
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+<span class="sourceLineNo">1505</span><a name="line.1505"></a>
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+<span class="sourceLineNo">1507</span> onDiskSizeWithHeaderL,<a name="line.1507"></a>
+<span class="sourceLineNo">1508</span> uncompressedSize, pread,<a name="line.1508"></a>
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+<span class="sourceLineNo">1510</span> if (blk == null) {<a name="line.1510"></a>
+<span class="sourceLineNo">1511</span> HFile.LOG.warn("HBase checksum verification failed for file " +<a name="line.1511"></a>
+<span class="sourceLineNo">1512</span> pathName + " at offset " +<a name="line.1512"></a>
+<span class="sourceLineNo">1513</span> offset + " filesize " + fileSize +<a name="line.1513"></a>
+<span class="sourceLineNo">1514</span> ". Retrying read with HDFS checksums turned on...");<a name="line.1514"></a>
+<span class="sourceLineNo">1515</span><a name="line.1515"></a>
+<span class="sourceLineNo">1516</span> if (!doVerificationThruHBaseChecksum) {<a name="line.1516"></a>
+<span class="sourceLineNo">1517</span> String msg = "HBase checksum verification failed for file " +<a name="line.1517"></a>
+<span class="sourceLineNo">1518</span> pathName + " at offset " +<a name="line.1518"></a>
+<span class="sourceLineNo">1519</span> offset + " filesize " + fileSize +<a name="line.1519"></a>
+<span class="sourceLineNo">1520</span> " but this cannot happen because doVerify is " +<a name="line.1520"></a>
+<span class="sourceLineNo">1521</span> doVerificationThruHBaseChecksum;<a name="line.1521"></a>
+<span class="sourceLineNo">1522</span> HFile.LOG.warn(msg);<a name="line.1522"></a>
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+<span class="sourceLineNo">1526</span><a name="line.1526"></a>
+<span class="sourceLineNo">1527</span> // If we have a checksum failure, we fall back into a mode where<a name="line.1527"></a>
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+<span class="sourceLineNo">1540</span> pathName + " at offset " +<a name="line.1540"></a>
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+<span class="sourceLineNo">1543</span> }<a name="line.1543"></a>
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+<span class="sourceLineNo">1546</span> "checksum verification failed for file " + pathName +<a name="line.1546"></a>
+<span class="sourceLineNo">1547</span> " at offset " + offset + " filesize " + fileSize;<a name="line.1547"></a>
+<span class="sourceLineNo">1548</span> HFile.LOG.warn(msg);<a name="line.1548"></a>
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+<span class="sourceLineNo">1558</span> // a negative number.<a name="line.1558"></a>
+<span class="sourceLineNo">1559</span> streamWrapper.checksumOk();<a name="line.1559"></a>
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+<span class="sourceLineNo">1579</span> throws IOException {<a name="line.1579"></a>
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+<span class="sourceLineNo">1582</span> + "block (onDiskSize=" + onDiskSizeWithHeaderL<a name="line.1582"></a>
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+<span class="sourceLineNo">1585</span><a name="line.1585"></a>
+<span class="sourceLineNo">1586</span> if (uncompressedSize != -1) {<a name="line.1586"></a>
+<span class="sourceLineNo">1587</span> throw new IOException("Version 2 block reader API does not need " +<a name="line.1587"></a>
+<span class="sourceLineNo">1588</span> "the uncompressed size parameter");<a name="line.1588"></a>
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+<span class="sourceLineNo">1590</span><a name="line.1590"></a>
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+<span class="sourceLineNo">1594</span> + ": expected to be at least " + hdrSize<a name="line.1594"></a>
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+<span class="sourceLineNo">1598</span><a name="line.1598"></a>
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+<span class="sourceLineNo">1600</span> // See if we can avoid reading the header. This is desirable, because<a name="line.1600"></a>
+<span class="sourceLineNo">1601</span> // we will not incur a backward seek op
<TRUNCATED>