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Example 6 with DbusEventGenerator

use of com.linkedin.databus.core.test.DbusEventGenerator in project databus by linkedin.

the class ReadEventsTestParams method testHeadDrift.

/**
 * TestCase to recreate the bug (DDSDBUS-387) where SCNIndex.head and EVB.Head do not match.
 */
@Test
public void testHeadDrift() throws Exception {
    // DbusEventBuffer.LOG.setLevel(Level.DEBUG);
    DbusEventBuffer dbusBuf = new DbusEventBuffer(getConfig(10000, 10000, 320, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.OVERWRITE_ON_WRITE, AssertLevel.ALL));
    DbusEventGenerator generator = new DbusEventGenerator();
    Vector<DbusEvent> events = new Vector<DbusEvent>();
    generator.generateEvents(215, 5, 100, 10, events);
    // Add events to the EventBuffer
    DbusEventAppender appender = new DbusEventAppender(events, dbusBuf, null);
    appender.run();
    LOG.info("Dbus Event Buffer is :" + dbusBuf);
    LOG.info("SCNIndex is :" + dbusBuf.getScnIndex());
    assertEquals("ScnIndex Head Location", 256, dbusBuf.getScnIndex().getHead());
    assertEquals("ScnIndex Tail Location", 256, dbusBuf.getScnIndex().getTail());
    assertEquals("EVB Head Location", 8381, dbusBuf.getHead());
    long oldEVBTail = 40733;
    assertEquals("EVB Tail Location", oldEVBTail, dbusBuf.getTail());
    dbusBuf.getScnIndex().printVerboseString(LOG, Level.DEBUG);
    long lastScn = events.get(events.size() - 1).sequence();
    generator = new DbusEventGenerator(lastScn + 1);
    events = new Vector<DbusEvent>();
    generator.generateEvents(3, 3, 80, 10, events);
    appender = new DbusEventAppender(events, dbusBuf, null);
    appender.run();
    // Ensure SCNINdex tail did not move.
    assertEquals("ScnIndex Head Location", 256, dbusBuf.getScnIndex().getHead());
    assertEquals("ScnIndex Tail Location", 256, dbusBuf.getScnIndex().getTail());
    assertEquals("EVB Head Location", 8381, dbusBuf.getHead());
    long newEVBTail = 41068;
    assertEquals("EVB Tail Location", newEVBTail, dbusBuf.getTail());
    // Make sure the EVB Tail did move. Old EVB Tail belongs to SCNINdex blockNumber 15 and new EVB tail to blockNumber 16
    assertEquals("Old EVB Tail's index block", 15, dbusBuf.getScnIndex().getBlockNumber(oldEVBTail));
    assertEquals("New EVB Tail's index block", 16, dbusBuf.getScnIndex().getBlockNumber(newEVBTail));
}
Also used : DbusEventAppender(com.linkedin.databus.core.test.DbusEventAppender) DbusEventGenerator(com.linkedin.databus.core.test.DbusEventGenerator) Vector(java.util.Vector) Test(org.testng.annotations.Test)

Example 7 with DbusEventGenerator

use of com.linkedin.databus.core.test.DbusEventGenerator in project databus by linkedin.

the class ReadEventsTestParams method testAppendEventOverlapNgt0.

// Case when n> 0
@Test
public void testAppendEventOverlapNgt0() throws Exception {
    final DbusEventBuffer dbusBuf = new DbusEventBuffer(getConfig(1145, 5000, 100, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.OVERWRITE_ON_WRITE, AssertLevel.ALL));
    BufferPositionParser parser = dbusBuf.getBufferPositionParser();
    DbusEventGenerator generator = new DbusEventGenerator();
    Vector<DbusEvent> events = new Vector<DbusEvent>();
    generator.generateEvents(9, 3, 120, 39, events);
    // Add events to the EventBuffer. Now the buffer is full
    DbusEventAppender appender = new DbusEventAppender(events, dbusBuf, null);
    // running in the same thread
    appender.run();
    LOG.info("Head:" + parser.toString(dbusBuf.getHead()) + ",Tail:" + parser.toString(dbusBuf.getTail()));
    long headPos = dbusBuf.getHead();
    long tailPos = dbusBuf.getTail();
    long scnIndexHead = dbusBuf.getScnIndex().getHead();
    long scnIndexTail = dbusBuf.getScnIndex().getTail();
    long headGenId = parser.bufferGenId(headPos);
    long headIndexId = parser.bufferIndex(headPos);
    long headOffset = parser.bufferOffset(headPos);
    long tailGenId = parser.bufferGenId(tailPos);
    long tailIndexId = parser.bufferIndex(tailPos);
    long tailOffset = parser.bufferOffset(tailPos);
    assertEquals("Head GenId", 0, headGenId);
    assertEquals("Head Index", 0, headIndexId);
    assertEquals("Head Offset", 0, headOffset);
    assertEquals("Tail GenId", 0, tailGenId);
    assertEquals("Tail Index", 0, tailIndexId);
    assertEquals("Tail Offset", 1144, tailOffset);
    assertEquals("SCNIndex Head", 0, scnIndexHead);
    assertEquals("SCNIndex Tail", 80, scnIndexTail);
    headPos = parser.setGenId(headPos, 300);
    tailPos = parser.setGenId(tailPos, 300);
    dbusBuf.setHead(headPos);
    dbusBuf.setTail(tailPos);
    dbusBuf.recreateIndex();
    events = new Vector<DbusEvent>();
    generator = new DbusEventGenerator(1000);
    /*
     * The event size is carefully created such that after adding 2nd
     * event CWP and tail points to the same location. Now the 3rd event corrupts the EVB and index (in the presence of bug).
     */
    generator.generateEvents(3, 2, 150, 89, events);
    appender = new DbusEventAppender(events, dbusBuf, null);
    LOG.info("1");
    // Logger.getRootLogger().setLevel(Level.ALL);
    // running in the same thread
    appender.run();
    LOG.info("2");
    LOG.info("Head:" + parser.toString(dbusBuf.getHead()) + ",Tail:" + parser.toString(dbusBuf.getTail()));
    headPos = dbusBuf.getHead();
    tailPos = dbusBuf.getTail();
    headGenId = parser.bufferGenId(headPos);
    headIndexId = parser.bufferIndex(headPos);
    headOffset = parser.bufferOffset(headPos);
    tailGenId = parser.bufferGenId(tailPos);
    tailIndexId = parser.bufferIndex(tailPos);
    tailOffset = parser.bufferOffset(tailPos);
    scnIndexHead = dbusBuf.getScnIndex().getHead();
    scnIndexTail = dbusBuf.getScnIndex().getTail();
    assertEquals("Head GenId", 300, headGenId);
    assertEquals("Head Index", 0, headIndexId);
    assertEquals("Head Offset", 783, headOffset);
    assertEquals("Tail GenId", 301, tailGenId);
    assertEquals("Tail Index", 0, tailIndexId);
    assertEquals("Tail Offset", 633, tailOffset);
    assertEquals("SCNIndex Head", 64, scnIndexHead);
    assertEquals("SCNIndex Tail", 48, scnIndexTail);
}
Also used : DbusEventAppender(com.linkedin.databus.core.test.DbusEventAppender) BufferPositionParser(com.linkedin.databus.core.util.BufferPositionParser) DbusEventGenerator(com.linkedin.databus.core.test.DbusEventGenerator) Vector(java.util.Vector) Test(org.testng.annotations.Test)

Example 8 with DbusEventGenerator

use of com.linkedin.databus.core.test.DbusEventGenerator in project databus by linkedin.

the class ReadEventsTestParams method testMissingEOWUnhappyPath.

/**
 * Testcase sends events with appropriate EOW events in between
 * valid packet, no EOW for prior packet, valid packet with a higher scn.
 * @throws Exception
 */
@Test
public void testMissingEOWUnhappyPath() throws Exception {
    final DbusEventBuffer dbusBuf = new DbusEventBuffer(getConfig(1000, 1000, 100, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.NONE));
    dbusBuf.setDropOldEvents(true);
    DbusEventGenerator generator = new DbusEventGenerator();
    Vector<DbusEvent> events = new Vector<DbusEvent>();
    generator.generateEvents(3, 1, 100, 10, events);
    // conversion of readable events to writable is for TESTING ONLY:
    DbusEventInternalWritable writableEvent = DbusEventCorrupter.makeWritable(events.get(1));
    // No EOW for event 0.
    writableEvent.setSequence(events.get(0).sequence() + 50);
    writableEvent.applyCrc();
    writableEvent = DbusEventCorrupter.makeWritable(events.get(2));
    // No EOW for event 1.
    writableEvent.setSequence(events.get(0).sequence() + 100);
    writableEvent.applyCrc();
    // Increment the SCN and reuse
    for (int i = 0; i < 3; ++i) {
        DbusEvent e = events.get(i);
        assertTrue("invalid event #" + i, e.isValid());
        LOG.info("DbusEvent " + i + " " + e);
    }
    // Set up the ReadChannel with 2 events
    ByteArrayOutputStream oStream = new ByteArrayOutputStream();
    WritableByteChannel oChannel = Channels.newChannel(oStream);
    for (int i = 0; i < 3; ++i) {
        ((DbusEventInternalReadable) events.get(i)).writeTo(oChannel, Encoding.BINARY);
    }
    byte[] writeBytes = oStream.toByteArray();
    ByteArrayInputStream iStream = new ByteArrayInputStream(writeBytes);
    final ReadableByteChannel rChannel = Channels.newChannel(iStream);
    try {
        dbusBuf.readEvents(rChannel);
        Assert.fail();
    } catch (InvalidEventException ie) {
        LOG.info("Exception trace is " + ie);
        return;
    }
}
Also used : ReadableByteChannel(java.nio.channels.ReadableByteChannel) DbusEventGenerator(com.linkedin.databus.core.test.DbusEventGenerator) WritableByteChannel(java.nio.channels.WritableByteChannel) ByteArrayOutputStream(java.io.ByteArrayOutputStream) ByteArrayInputStream(java.io.ByteArrayInputStream) Vector(java.util.Vector) Test(org.testng.annotations.Test)

Example 9 with DbusEventGenerator

use of com.linkedin.databus.core.test.DbusEventGenerator in project databus by linkedin.

the class ReadEventsTestParams method testBufferOverFlow.

/*
   * TestCase to recreate the BufferOverFlowException issue tracked in DDS-793
   */
@Test
public void testBufferOverFlow() throws Exception {
    // DbusEventBuffer.LOG.setLevel(Level.DEBUG);
    final Logger log = Logger.getLogger("TestDbusEventBuffer.testBufferOverflow");
    // log.setLevel(Level.INFO);
    log.info("starting");
    DbusEventBuffer dbusBuf = new DbusEventBuffer(getConfig(1000, 1000, 100, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.ALL));
    final DbusEventBuffer dbusBuf2 = new DbusEventBuffer(getConfig(2000, 2000, 100, 1000, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.NONE));
    BufferPositionParser parser = dbusBuf.getBufferPositionParser();
    final BufferPositionParser parser2 = dbusBuf2.getBufferPositionParser();
    DbusEventGenerator generator = new DbusEventGenerator();
    Vector<DbusEvent> events = new Vector<DbusEvent>();
    generator.generateEvents(12, 12, 100, 10, events);
    log.info("generate sample events to the EventBuffer");
    DbusEventAppender appender = new DbusEventAppender(events, dbusBuf, null);
    appender.run();
    log.info("dbusBuf : Head:" + parser.toString(dbusBuf.getHead()) + ",Tail:" + parser.toString(dbusBuf.getTail()));
    ByteBuffer[] buf = dbusBuf.getBuffer();
    byte[] b = new byte[(int) dbusBuf.getTail()];
    buf[0].position(0);
    buf[0].get(b);
    log.info("copy data to the destination buffer: 1");
    ReadableByteChannel rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    dbusBuf2.readEvents(rChannel);
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    rChannel.close();
    log.info("copy data to the destination buffer: 2");
    rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    dbusBuf2.readEvents(rChannel);
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("Buffer Size is :" + dbusBuf2.getBuffer().length);
    rChannel.close();
    log.info("process data in destination buffer: 1");
    DbusEventBuffer.DbusEventIterator itr = dbusBuf2.acquireIterator("dummy1");
    for (int i = 0; i < 15; i++) {
        itr.next();
        itr.remove();
    }
    itr.close();
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("copy data to the destination buffer: 3");
    rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    dbusBuf2.readEvents(rChannel);
    ByteBuffer[] buf2 = dbusBuf2.getBuffer();
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("dbusBuf2 : Buffer :" + buf2[0]);
    rChannel.close();
    log.info("process data in destination buffer: 2");
    itr = dbusBuf2.acquireIterator("dummy2");
    for (int i = 0; i < 15; i++) {
        itr.next();
        itr.remove();
    }
    itr.close();
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("dbusBuf2 : Buffer :" + buf2[0]);
    log.info("generate more sample events to the EventBuffer");
    dbusBuf = new DbusEventBuffer(getConfig(2000, 2000, 100, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.ALL));
    events = new Vector<DbusEvent>();
    generator.generateEvents(8, 9, 150, 52, events);
    log.info("Events Size is :" + events.get(0).size());
    appender = new DbusEventAppender(events, dbusBuf, null);
    appender.run();
    final AtomicBoolean stopReader = new AtomicBoolean(false);
    Runnable reader = new Runnable() {

        @Override
        public void run() {
            try {
                Thread.sleep(5 * 1000);
            } catch (InterruptedException ie) {
            }
            DbusEventBuffer.DbusEventIterator itr = dbusBuf2.acquireIterator("dummy3");
            log.info("Reader iterator:" + itr);
            while (!stopReader.get() || itr.hasNext()) {
                while (itr.hasNext()) {
                    itr.next();
                    itr.remove();
                }
                itr.await(100, TimeUnit.MILLISECONDS);
            }
            itr.close();
            log.info("Reader Thread: dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
            ByteBuffer[] buf = dbusBuf2.getBuffer();
            log.info("Reader Tread : dbusBuf2 : Buffer :" + buf[0]);
            log.info("Reader iterator:" + itr);
        }
    };
    log.info("generate sample events to the EventBuffer");
    Thread t = new Thread(reader, "BufferOverflowReader");
    b = new byte[(int) dbusBuf.getTail()];
    buf = dbusBuf.getBuffer();
    buf[0].position(0);
    buf[0].get(b);
    log.info("copy data to the destination buffer: 4");
    log.info("Size is :" + b.length);
    rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    // <=== Overflow happened at this point
    dbusBuf2.readEvents(rChannel);
    rChannel.close();
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("dbusBuf2 : Buffer :" + buf2[0]);
    log.info("test if the readEvents can allow reader to proceed while it is blocked");
    rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    log.info("start reader thread");
    t.start();
    log.info("copy data to the destination buffer: 5");
    dbusBuf2.readEvents(rChannel);
    rChannel.close();
    log.info("data copied to the destination buffer: 5");
    stopReader.set(true);
    t.join(20000);
    log.info("check if dbusBuf2 is empty");
    Assert.assertTrue(!t.isAlive());
    if (!dbusBuf2.empty()) {
        log.error("dbusBuf2 not empty: " + dbusBuf2);
    }
    Assert.assertTrue(dbusBuf2.toString(), dbusBuf2.empty());
    log.info("dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
    log.info("dbusBuf2 : Buffer :" + buf2[0]);
    log.info("done");
}
Also used : DbusEventAppender(com.linkedin.databus.core.test.DbusEventAppender) ReadableByteChannel(java.nio.channels.ReadableByteChannel) DbusEventGenerator(com.linkedin.databus.core.test.DbusEventGenerator) Logger(org.apache.log4j.Logger) ByteBuffer(java.nio.ByteBuffer) UncaughtExceptionTrackingThread(com.linkedin.databus.core.util.UncaughtExceptionTrackingThread) DbusEventIterator(com.linkedin.databus.core.DbusEventBuffer.DbusEventIterator) AtomicBoolean(java.util.concurrent.atomic.AtomicBoolean) BufferPositionParser(com.linkedin.databus.core.util.BufferPositionParser) ByteArrayInputStream(java.io.ByteArrayInputStream) Vector(java.util.Vector) Test(org.testng.annotations.Test)

Example 10 with DbusEventGenerator

use of com.linkedin.databus.core.test.DbusEventGenerator in project databus by linkedin.

the class ReadEventsTestParams method testBigReadEventBuffer.

@Test
public /*
   * ReadBuffer Size is bigger than the overall EVB size.
   * A large read happens to EVB which is bigger than its size.
   */
void testBigReadEventBuffer() throws Exception {
    final Logger log = Logger.getLogger("TestDbusEventBuffer.testBigReadEventBuffer");
    // log.setLevel(Level.INFO);
    log.info("starting");
    final DbusEventBuffer dbusBuf = new DbusEventBuffer(getConfig(4000, 4000, 100, 500, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.ALL));
    final DbusEventBuffer dbusBuf2 = new DbusEventBuffer(getConfig(1000, 1000, 100, 3000, AllocationPolicy.HEAP_MEMORY, QueuePolicy.BLOCK_ON_WRITE, AssertLevel.NONE));
    // dbusBuf2.getLog().setLevel(Level.DEBUG);
    BufferPositionParser parser = dbusBuf.getBufferPositionParser();
    final BufferPositionParser parser2 = dbusBuf2.getBufferPositionParser();
    DbusEventGenerator generator = new DbusEventGenerator();
    Vector<DbusEvent> events = new Vector<DbusEvent>();
    generator.generateEvents(24, 24, 100, 10, events);
    log.info("Num Events :" + events.size());
    // Add events to the EventBuffer
    DbusEventAppender appender = new DbusEventAppender(events, dbusBuf, null);
    appender.run();
    final AtomicBoolean stopReader = new AtomicBoolean(false);
    log.info("dbusBuf : Head:" + parser.toString(dbusBuf.getHead()) + ",Tail:" + parser.toString(dbusBuf.getTail()));
    class EvbReader implements Runnable {

        private int _count = 0;

        public EvbReader() {
            _count = 0;
        }

        public int getCount() {
            return _count;
        }

        @Override
        public void run() {
            try {
                Thread.sleep(5 * 1000);
            } catch (InterruptedException ie) {
            }
            DbusEventBuffer.DbusEventIterator itr = dbusBuf2.acquireIterator("dummy");
            log.info("Reader iterator:" + itr);
            while (!stopReader.get() || itr.hasNext()) {
                while (itr.hasNext()) {
                    itr.next();
                    itr.remove();
                    _count++;
                }
                itr.await(100, TimeUnit.MILLISECONDS);
            }
            log.info("Reader Thread: dbusBuf2 : Head:" + parser2.toString(dbusBuf2.getHead()) + ",Tail:" + parser2.toString(dbusBuf2.getTail()));
            ByteBuffer[] buf = dbusBuf2.getBuffer();
            log.info("Reader Thread : dbusBuf2 : Buffer :" + buf[0]);
            log.info("Count is :" + _count);
            log.info("Reader iterator:" + itr);
        }
    }
    ;
    EvbReader reader = new EvbReader();
    Thread t = new Thread(reader, "BigReadEventReader");
    ByteBuffer[] buf = dbusBuf.getBuffer();
    byte[] b = new byte[(int) dbusBuf.getTail()];
    buf[0].position(0);
    buf[0].get(b);
    ReadableByteChannel rChannel = Channels.newChannel(new ByteArrayInputStream(b));
    t.start();
    dbusBuf2.readEvents(rChannel);
    stopReader.set(true);
    t.join(20000);
    Assert.assertTrue(!t.isAlive());
    DbusEventBuffer.DbusEventIterator itr2 = dbusBuf2.acquireIterator("dummy");
    int count = 0;
    while (itr2.hasNext()) {
        itr2.next();
        itr2.remove();
        count++;
    }
    log.info("Total Count :" + (count + reader.getCount()));
    log.info("Head :" + dbusBuf2.getHead() + ", Tail :" + dbusBuf2.getTail());
    assertEquals("Total Count", 26, (count + reader.getCount()));
    assertEquals("Head == Tail", dbusBuf2.getHead(), dbusBuf2.getTail());
    assertEquals("Head Check:", 2890, dbusBuf2.getHead());
    log.info("done");
}
Also used : DbusEventAppender(com.linkedin.databus.core.test.DbusEventAppender) ReadableByteChannel(java.nio.channels.ReadableByteChannel) DbusEventGenerator(com.linkedin.databus.core.test.DbusEventGenerator) Logger(org.apache.log4j.Logger) ByteBuffer(java.nio.ByteBuffer) UncaughtExceptionTrackingThread(com.linkedin.databus.core.util.UncaughtExceptionTrackingThread) DbusEventIterator(com.linkedin.databus.core.DbusEventBuffer.DbusEventIterator) AtomicBoolean(java.util.concurrent.atomic.AtomicBoolean) BufferPositionParser(com.linkedin.databus.core.util.BufferPositionParser) ByteArrayInputStream(java.io.ByteArrayInputStream) Vector(java.util.Vector) Test(org.testng.annotations.Test)

Aggregations

DbusEventGenerator (com.linkedin.databus.core.test.DbusEventGenerator)40 Vector (java.util.Vector)39 Test (org.testng.annotations.Test)34 DbusEventAppender (com.linkedin.databus.core.test.DbusEventAppender)27 Logger (org.apache.log4j.Logger)17 UncaughtExceptionTrackingThread (com.linkedin.databus.core.util.UncaughtExceptionTrackingThread)16 ByteArrayInputStream (java.io.ByteArrayInputStream)11 ReadableByteChannel (java.nio.channels.ReadableByteChannel)11 ByteArrayOutputStream (java.io.ByteArrayOutputStream)10 WritableByteChannel (java.nio.channels.WritableByteChannel)10 DatabusV2ConsumerRegistration (com.linkedin.databus.client.consumer.DatabusV2ConsumerRegistration)8 MultiConsumerCallback (com.linkedin.databus.client.consumer.MultiConsumerCallback)8 StreamConsumerCallbackFactory (com.linkedin.databus.client.consumer.StreamConsumerCallbackFactory)8 Checkpoint (com.linkedin.databus.core.Checkpoint)8 DbusEvent (com.linkedin.databus.core.DbusEvent)8 DatabusSubscription (com.linkedin.databus.core.data_model.DatabusSubscription)8 BufferPositionParser (com.linkedin.databus.core.util.BufferPositionParser)8 IdNamePair (com.linkedin.databus.core.util.IdNamePair)8 RegisterResponseEntry (com.linkedin.databus2.core.container.request.RegisterResponseEntry)8 SelectingDatabusCombinedConsumer (com.linkedin.databus.client.consumer.SelectingDatabusCombinedConsumer)7