Java Code Examples for org.apache.distributedlog.api.LogReader#close()

The following examples show how to use org.apache.distributedlog.api.LogReader#close() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example 1

Source File: TestTruncate.java From distributedlog with Apache License 2.0

6 votes

private void verifyEntries(String name, long readFromTxId, long startTxId, int numEntries) throws Exception {
    DistributedLogManager dlm = createNewDLM(conf, name);
    LogReader reader = dlm.getInputStream(readFromTxId);

    long txid = startTxId;
    int numRead = 0;
    LogRecord r = reader.readNext(false);
    while (null != r) {
        DLMTestUtil.verifyLogRecord(r);
        assertEquals(txid++, r.getTransactionId());
        ++numRead;
        r = reader.readNext(false);
    }
    assertEquals(numEntries, numRead);
    reader.close();
    dlm.close();
}

Example 2

Source File: TestDistributedLogTool.java From distributedlog with Apache License 2.0

6 votes

@Test(timeout = 60000)
public void testToolTruncateStream() throws Exception {
    DistributedLogConfiguration confLocal = new DistributedLogConfiguration();
    confLocal.addConfiguration(conf);
    confLocal.setLogSegmentCacheEnabled(false);
    DistributedLogManager dlm = DLMTestUtil.createNewDLM("testToolTruncateStream", confLocal, defaultUri);
    DLMTestUtil.generateCompletedLogSegments(dlm, confLocal, 3, 1000);

    DLSN dlsn = new DLSN(2, 1, 0);
    TruncateStreamCommand cmd = new TruncateStreamCommand();
    cmd.setDlsn(dlsn);
    cmd.setUri(defaultUri);
    cmd.setStreamName("testToolTruncateStream");
    cmd.setForce(true);

    assertEquals(0, cmd.runCmd());

    LogReader reader = dlm.getInputStream(0);
    LogRecordWithDLSN record = reader.readNext(false);
    assertEquals(dlsn, record.getDlsn());

    reader.close();
    dlm.close();
}

Example 3

Source File: TestNonBlockingReads.java From distributedlog with Apache License 2.0

6 votes

@Test(timeout = 15000)
public void testHandleInconsistentMetadataDLSNNonBlocking() throws Exception {
    String name = "distrlog-inconsistent-metadata-nonblocking-read-dlsn";
    long numRecordsWritten = createStreamWithInconsistentMetadata(name);

    DistributedLogManager dlm = createNewDLM(conf, name);
    try {
        LogReader reader = dlm.getInputStream(DLSN.InitialDLSN);
        long numRecordsRead = 0;
        long lastTxId = -1;
        while (numRecordsRead < numRecordsWritten) {
            LogRecord record = reader.readNext(false);
            if (record != null) {
                DLMTestUtil.verifyLogRecord(record);
                Assert.assertTrue(lastTxId < record.getTransactionId());
                lastTxId = record.getTransactionId();
                numRecordsRead++;
            } else {
                Thread.sleep(1);
            }
        }
        reader.close();
    } finally {
        dlm.close();
    }
}

Example 4

Source File: TestNonBlockingReads.java From distributedlog with Apache License 2.0

6 votes

@Test(timeout = 15000)
public void testHandleInconsistentMetadataNonBlocking() throws Exception {
    String name = "distrlog-inconsistent-metadata-nonblocking-read";
    long numRecordsWritten = createStreamWithInconsistentMetadata(name);

    DistributedLogManager dlm = createNewDLM(conf, name);
    try {
        LogReader reader = dlm.getInputStream(45);
        long numRecordsRead = 0;
        long lastTxId = -1;
        while (numRecordsRead < (numRecordsWritten / 2)) {
            LogRecord record = reader.readNext(false);
            if (record != null) {
                DLMTestUtil.verifyLogRecord(record);
                Assert.assertTrue(lastTxId < record.getTransactionId());
                lastTxId = record.getTransactionId();
                numRecordsRead++;
            } else {
                Thread.sleep(1);
            }
        }
        reader.close();
    } finally {
        dlm.close();
    }
}

Example 5

Source File: DistributedLogTool.java From distributedlog with Apache License 2.0

5 votes

int countFromStartToEnd(DistributedLogManager dlm) throws Exception {
    int count = 0;
    try {
        LogReader reader = dlm.getInputStream(startDLSN);
        try {
            LogRecordWithDLSN record = reader.readNext(false);
            LogRecordWithDLSN preRecord = record;
            System.out.println("first record : " + record);
            while (null != record) {
                if (record.getDlsn().compareTo(endDLSN) > 0) {
                    break;
                }
                ++count;
                if (count % 1000 == 0) {
                    logger.info("read {} records from {}...", count, getStreamName());
                }
                preRecord = record;
                record = reader.readNext(false);
            }
            System.out.println("last record : " + preRecord);
        } finally {
            reader.close();
        }
    } finally {
        dlm.close();
    }
    return count;
}

Example 6

Source File: TestNonBlockingReads.java From distributedlog with Apache License 2.0

5 votes

@Test(timeout = 60000)
public void testHandleInconsistentMetadata() throws Exception {
    String name = "distrlog-inconsistent-metadata-blocking-read";
    long numRecordsWritten = createStreamWithInconsistentMetadata(name);

    DistributedLogManager dlm = createNewDLM(conf, name);
    try {
        LogReader reader = dlm.getInputStream(45);
        long numRecordsRead = 0;
        LogRecord record = reader.readNext(false);
        long lastTxId = -1;
        while (numRecordsRead < numRecordsWritten / 2) {
            if (null != record) {
                DLMTestUtil.verifyLogRecord(record);
                Assert.assertTrue(lastTxId < record.getTransactionId());
                lastTxId = record.getTransactionId();
                numRecordsRead++;
            } else {
                Thread.sleep(1);
            }
            record = reader.readNext(false);
        }
        reader.close();
        assertEquals(numRecordsWritten / 2, numRecordsRead);
    } finally {
        dlm.close();
    }
}

Example 7

Source File: TestBKSyncLogReader.java From distributedlog with Apache License 2.0

5 votes

@Test(timeout = 60000)
public void testReadingFromEmptyLog() throws Exception {
    String name = testName.getMethodName();
    DistributedLogConfiguration confLocal = new DistributedLogConfiguration();
    confLocal.addConfiguration(conf);
    confLocal.setOutputBufferSize(0);
    confLocal.setPeriodicFlushFrequencyMilliSeconds(Integer.MAX_VALUE);

    DistributedLogManager dlm = createNewDLM(confLocal, name);
    BKSyncLogWriter out = (BKSyncLogWriter) dlm.startLogSegmentNonPartitioned();
    // write a record but not commit
    LogRecord op = DLMTestUtil.getLogRecordInstance(1L);
    out.write(op);

    LogReader reader = dlm.getInputStream(1L);
    assertNull(reader.readNext(true));
    assertNull(reader.readNext(false));

    op = DLMTestUtil.getLogRecordInstance(2L);
    out.write(op);

    // reader is able to read first record
    LogRecord record = waitForNextRecord(reader);
    assertNotNull(record);
    assertEquals(1L, record.getTransactionId());
    DLMTestUtil.verifyLogRecord(record);

    assertNull(reader.readNext(true));

    out.close();
    reader.close();
    dlm.close();
}

Example 8

Source File: DLMTestUtil.java From distributedlog with Apache License 2.0

5 votes

static long getNumberofLogRecords(DistributedLogManager bkdlm, long startTxId) throws IOException {
    long numLogRecs = 0;
    LogReader reader = bkdlm.getInputStream(startTxId);
    LogRecord record = reader.readNext(false);
    while (null != record) {
        numLogRecs++;
        verifyLogRecord(record);
        record = reader.readNext(false);
    }
    reader.close();
    return numLogRecs;
}

Example 9

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

5 votes

@Test(timeout = 60000)
public void testInterleavedReaders() throws Exception {
    String name = "distrlog-interleaved";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    BKDistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");

    LogReader reader0 = null;
    LogReader reader1 = null;
    long txid = 1;
    int numTrans = 0;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 4; j++) {
        for (int k = 1; k <= 10; k++) {
            Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        if (null == reader0) {
            reader0 = dlmreader0.getInputStream(1);
        }
        if (null == reader1) {
            reader1 = dlmreader1.getInputStream(1);
        }
        numTrans += drainStreams(reader0, 10, reader1, 10);
        assertEquals((txid - 1), numTrans);
    }
    reader0.close();
    reader1.close();
    dlmreader0.close();
    dlmwrite0.close();
    dlmreader1.close();
    dlmwrite1.close();
}

Example 10

Source File: TestRollLogSegments.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testUnableToRollLogSegments() throws Exception {
    String name = "distrlog-unable-to-roll-log-segments";
    DistributedLogConfiguration confLocal = new DistributedLogConfiguration();
    confLocal.loadConf(conf);
    confLocal.setImmediateFlushEnabled(true);
    confLocal.setOutputBufferSize(0);
    confLocal.setLogSegmentRollingIntervalMinutes(0);
    confLocal.setMaxLogSegmentBytes(1);

    DistributedLogManager dlm = createNewDLM(confLocal, name);
    BKAsyncLogWriter writer = (BKAsyncLogWriter) dlm.startAsyncLogSegmentNonPartitioned();

    long txId = 1L;

    // Create Log Segments
    Utils.ioResult(writer.write(DLMTestUtil.getLogRecordInstance(txId)));

    FailpointUtils.setFailpoint(FailpointUtils.FailPointName.FP_StartLogSegmentBeforeLedgerCreate,
            FailpointUtils.FailPointActions.FailPointAction_Throw);

    try {
        // If we couldn't open new log segment, we should keep using the old one
        final int numRecords = 10;
        final CountDownLatch latch = new CountDownLatch(numRecords);
        for (int i = 0; i < numRecords; i++) {
            writer.write(DLMTestUtil.getLogRecordInstance(++txId)).whenComplete(new FutureEventListener<DLSN>() {
                @Override
                public void onSuccess(DLSN value) {
                    logger.info("Completed entry : {}.", value);
                    latch.countDown();
                }
                @Override
                public void onFailure(Throwable cause) {
                    logger.error("Failed to write entries : ", cause);
                }
            });
        }

        latch.await();

        writer.close();

        List<LogSegmentMetadata> segments = dlm.getLogSegments();
        logger.info("LogSegments: {}", segments);

        assertEquals(1, segments.size());

        long expectedTxID = 1L;
        LogReader reader = dlm.getInputStream(DLSN.InitialDLSN);
        LogRecordWithDLSN record = reader.readNext(false);
        while (null != record) {
            DLMTestUtil.verifyLogRecord(record);
            assertEquals(expectedTxID++, record.getTransactionId());
            assertEquals(record.getTransactionId() - 1, record.getSequenceId());

            record = reader.readNext(false);
        }

        assertEquals(12L, expectedTxID);

        reader.close();

        dlm.close();
    } finally {
        FailpointUtils.removeFailpoint(FailpointUtils.FailPointName.FP_StartLogSegmentBeforeLedgerCreate);
    }
}

Example 11

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testInterleavedReadersWithRollingEdgeUnPartitioned() throws Exception {
    String name = "distrlog-interleaved-rolling-edge-unpartitioned";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    BKDistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");

    LogReader reader0 = null;
    LogReader reader1 = null;
    long txid = 1;
    int numTrans = 0;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 4; j++) {
        if (j > 1) {
            writer0.setForceRolling(true);
            writer1.setForceRolling(true);
        }
        for (int k = 1; k <= 2; k++) {
            Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
            writer0.setForceRolling(false);
            writer1.setForceRolling(false);
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        if (null == reader0) {
            reader0 = dlmreader0.getInputStream(1);
        }
        if (null == reader1) {
            reader1 = dlmreader1.getInputStream(1);
        }
        numTrans += drainStreams(reader0, 2, reader1, 2);
        assertEquals((txid - 1), numTrans);
    }
    reader0.close();
    reader1.close();
    dlmreader0.close();
    dlmreader1.close();
}

Example 12

Source File: TestBKDistributedLogManager.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void deleteDuringRead() throws Exception {
    String name = "distrlog-delete-with-reader";
    DistributedLogManager dlm = createNewDLM(conf, name);

    long txid = 1;
    for (long i = 0; i < 3; i++) {
        long start = txid;
        BKSyncLogWriter writer = (BKSyncLogWriter) dlm.startLogSegmentNonPartitioned();
        for (long j = 1; j <= DEFAULT_SEGMENT_SIZE; j++) {
            writer.write(DLMTestUtil.getLogRecordInstance(txid++));
        }

        BKLogSegmentWriter perStreamLogWriter = writer.getCachedLogWriter();

        writer.closeAndComplete();
        BKLogWriteHandler blplm = ((BKDistributedLogManager) (dlm)).createWriteHandler(true);
        assertNotNull(zkc.exists(blplm.completedLedgerZNode(start, txid - 1,
                perStreamLogWriter.getLogSegmentSequenceNumber()), false));
        Utils.ioResult(blplm.asyncClose());
    }

    LogReader reader = dlm.getInputStream(1);
    LogRecord record = reader.readNext(false);
    assert (null != record);
    DLMTestUtil.verifyLogRecord(record);
    long lastTxId = record.getTransactionId();

    dlm.delete();

    boolean exceptionEncountered;
    try {
        record = reader.readNext(false);
        while (null != record) {
            DLMTestUtil.verifyLogRecord(record);
            assert (lastTxId < record.getTransactionId());
            lastTxId = record.getTransactionId();
            record = reader.readNext(false);
        }
        // make sure the exception is thrown from readahead
        while (true) {
            reader.readNext(false);
        }
    } catch (LogReadException | LogNotFoundException | DLIllegalStateException e) {
        exceptionEncountered = true;
    }
    assertTrue(exceptionEncountered);
    reader.close();
}

Example 13

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testInterleavedReadersWithRecovery() throws Exception {
    String name = "distrlog-interleaved-recovery";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    BKDistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");

    LogReader reader0 = null;
    LogReader reader1 = null;
    long txid = 1;
    int numTrans = 0;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 2; j++) {
        for (int k = 1; k <= 6; k++) {
            if (k == 3) {
                writer0.setForceRecovery(true);
                writer1.setForceRecovery(true);
            }
            DLSN dlsn1 = Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            LOG.info("writer1 write record {} - txid = {}", dlsn1, txid - 1);
            DLSN dlsn0 = Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
            LOG.info("writer0 write record {} - txid = {}", dlsn0, txid - 1);
            writer0.setForceRecovery(false);
            writer1.setForceRecovery(false);
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        if (null == reader0) {
            reader0 = dlmreader0.getInputStream(1);
        }
        if (null == reader1) {
            reader1 = dlmreader1.getInputStream(1);
        }
        numTrans += drainStreams(reader0, 6, reader1, 6);
        assertEquals((txid - 1), numTrans);
    }
    reader0.close();
    reader1.close();
    assertEquals(txid - 1,
        dlmreader0.getLogRecordCount() + dlmreader1.getLogRecordCount());
    dlmreader0.close();
    dlmwrite0.close();
    dlmreader1.close();
    dlmwrite1.close();
}

Example 14

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testInterleavedReadersWithCleanup() throws Exception {
    String name = "distrlog-interleaved-cleanup";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    long txid = 1;
    Long retentionPeriodOverride = null;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 4; j++) {
        for (int k = 1; k <= 10; k++) {
            if (k == 5) {
                writer0.setForceRolling(true);
                writer0.overRideMinTimeStampToKeep(retentionPeriodOverride);
                writer1.setForceRolling(true);
                writer1.overRideMinTimeStampToKeep(retentionPeriodOverride);
            }
            DLSN dlsn1 = Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            LOG.info("writer1 write record {}", dlsn1);
            DLSN dlsn0 = Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
            LOG.info("writer0 write record {}", dlsn0);
            if (k == 5) {
                writer0.setForceRolling(false);
                writer1.setForceRolling(false);
                retentionPeriodOverride = System.currentTimeMillis();
            }
            Thread.sleep(5);
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
    }
    writer0.close();
    writer1.close();

    DistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    DistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");
    LogReader reader0 = dlmreader0.getInputStream(1);
    LogReader reader1 = dlmreader1.getInputStream(1);
    int numTrans = drainStreams(reader0, 15, reader1, 15);
    assertEquals(30, numTrans);
    reader0.close();
    reader1.close();
    dlmreader0.close();
    dlmwrite0.close();
    dlmreader1.close();
    dlmwrite1.close();
}

Example 15

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testInterleavedReadersWithRolling() throws Exception {
    String name = "distrlog-interleaved-rolling";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    BKDistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");

    LogReader reader0 = null;
    LogReader reader1 = null;
    long txid = 1;
    int numTrans = 0;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 2; j++) {
        for (int k = 1; k <= 6; k++) {
            if (k == 3) {
                writer0.setForceRolling(true);
                writer1.setForceRolling(true);
            }
            Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
            writer0.setForceRolling(false);
            writer1.setForceRolling(false);
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        if (null == reader0) {
            reader0 = dlmreader0.getInputStream(1);
        }
        if (null == reader1) {
            reader1 = dlmreader1.getInputStream(1);
        }
        numTrans += drainStreams(reader0, 6, reader1, 6);
        assertEquals((txid - 1), numTrans);
    }
    reader0.close();
    reader1.close();
    dlmreader0.close();
    dlmwrite0.close();
    dlmreader1.close();
    dlmwrite1.close();
}

Example 16

Source File: TestInterleavedReaders.java From distributedlog with Apache License 2.0

4 votes

@Test(timeout = 60000)
public void testInterleavedReadersWithRollingEdge() throws Exception {
    String name = "distrlog-interleaved-rolling-edge";
    BKDistributedLogManager dlmwrite0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmreader0 = createNewDLM(conf, name + "-0");
    BKDistributedLogManager dlmwrite1 = createNewDLM(conf, name + "-1");
    BKDistributedLogManager dlmreader1 = createNewDLM(conf, name + "-1");

    LogReader reader0 = null;
    LogReader reader1 = null;
    long txid = 1;
    int numTrans = 0;

    BKAsyncLogWriter writer0 = dlmwrite0.startAsyncLogSegmentNonPartitioned();
    BKAsyncLogWriter writer1 = dlmwrite1.startAsyncLogSegmentNonPartitioned();
    for (long j = 1; j <= 4; j++) {
        if (j > 1) {
            writer0.setForceRolling(true);
            writer1.setForceRolling(true);
        }
        for (int k = 1; k <= 2; k++) {
            Utils.ioResult(writer1.write(DLMTestUtil.getLogRecordInstance(txid++)));
            Utils.ioResult(writer0.write(DLMTestUtil.getLogRecordInstance(txid++)));
            writer0.setForceRolling(false);
            writer1.setForceRolling(false);
        }
        Utils.ioResult(writer1.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        Utils.ioResult(writer0.writeControlRecord(DLMTestUtil.getLogRecordInstance(txid - 1)));
        LOG.info("Completed {} write", j);
        if (null == reader0) {
            reader0 = dlmreader0.getInputStream(1);
        }
        if (null == reader1) {
            reader1 = dlmreader1.getInputStream(1);
        }
        numTrans += drainStreams(reader0, 2, reader1, 2);
        assertEquals((txid - 1), numTrans);
    }
    reader0.close();
    reader1.close();
    dlmreader0.close();
    dlmwrite0.close();
    dlmreader1.close();
    dlmwrite1.close();
}

Example 17

Source File: AppendOnlyStreamReader.java From distributedlog with Apache License 2.0

4 votes

/**
 * Position the reader at the given offset. If we fail to skip to the desired position
 * and don't hit end of stream, return false.
 *
 * @throws org.apache.distributedlog.exceptions.EndOfStreamException if we attempt to
 *         skip past the end of the stream.
 */
public boolean skipTo(long position) throws IOException {

    // No need to skip anywhere.
    if (position == position()) {
        return true;
    }

    LogReader skipReader = dlm.getInputStream(position);
    LogRecordWithInputStream logRecord = null;
    try {
        logRecord = nextLogRecord(skipReader);
    } catch (IOException ex) {
        skipReader.close();
        throw ex;
    }

    if (null == logRecord) {
        return false;
    }

    // We may end up with a reader positioned *before* the requested position if
    // we're near the tail and the writer is still active, or if the desired position
    // is not at a log record payload boundary.
    // Transaction ID gives us the starting position of the log record. Read ahead
    // if necessary.
    currentPosition = logRecord.getOffset();
    currentLogRecord = logRecord;
    LogReader oldReader = reader;
    reader = skipReader;

    // Close the oldreader after swapping AppendOnlyStreamReader state. Close may fail
    // and we need to make sure it leaves AppendOnlyStreamReader in a consistent state.
    oldReader.close();

    byte[] skipBuffer = new byte[SKIP_BUFFER_SIZE];
    while (currentPosition < position) {
        long bytesToRead = Math.min(position - currentPosition, SKIP_BUFFER_SIZE);
        long bytesRead = read(skipBuffer, 0, (int) bytesToRead);
        if (bytesRead < bytesToRead) {
            return false;
        }
    }

    return true;
}