org.apache.drill.exec.physical.rowSet

Class TestOffsetVectorWriter

java.lang.Object

org.apache.drill.test.BaseTest

org.apache.drill.test.DrillTest

org.apache.drill.test.SubOperatorTest

org.apache.drill.exec.physical.rowSet.TestOffsetVectorWriter

public class TestOffsetVectorWriter
extends SubOperatorTest

The offset vector writer is unique: it follows the same API as the other writers, but has a unique twist because offsets are written into the slot one after the other vectors. That is, if we are writing row 5, the offset vector writer writes to position 6. This is done to write the end offset of row 5 as the start offset of row 6. (It does, however, waste space as we need twice the number of elements in the offset vector as other vectors when writing power-of-two record counts.)

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.drill.test.DrillTest

DrillTest.MemWatcher

Field Summary

Fields inherited from class org.apache.drill.test.SubOperatorTest

dirTestWatcher, fixture

Fields inherited from class org.apache.drill.test.DrillTest

logOutcome, objectMapper, REPEAT_RULE, thrownException, TIMEOUT

Constructor Summary

Constructors

Constructor and Description
TestOffsetVectorWriter()

Method Summary

Modifier and Type	Method and Description
static void	setup() Party over enough memory that the uninitialized nature of vectors under the new writers will cause test to fail if the writer's don't correctly fill in all values.
void	testFillEmpties() Offset vectors have specific behavior when back-filling missing values: the last offset must be carried forward into the missing slots.
void	testRestartRow()
void	testRollover() The rollover method is used during vector overflow.
void	testRolloverWithEmpties() Simulate the case in which the tail end of an overflow batch has empties.
void	testSizeLimit() Test resize monitoring.
void	testWrite() Basic test to write a contiguous set of offsets, enough to cause the vector to double in size twice, then read back the values.

Methods inherited from class org.apache.drill.test.SubOperatorTest

classSetup, classTeardown

Methods inherited from class org.apache.drill.test.DrillTest

escapeJsonString, finishDrillTest, initDrillTest

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TestOffsetVectorWriter

public TestOffsetVectorWriter()

Method Detail

setup

public static void setup()

Party over enough memory that the uninitialized nature of vectors under the new writers will cause test to fail if the writer's don't correctly fill in all values.

testWrite

public void testWrite()

Basic test to write a contiguous set of offsets, enough to cause the vector to double in size twice, then read back the values.

testRestartRow

public void testRestartRow()

testFillEmpties

public void testFillEmpties()

Offset vectors have specific behavior when back-filling missing values: the last offset must be carried forward into the missing slots. The slots cannot be zero-filled, or entries will end up with a negative length.

testRollover

public void testRollover()

The rollover method is used during vector overflow.

testRolloverWithEmpties

public void testRolloverWithEmpties()

Simulate the case in which the tail end of an overflow batch has empties. preRollover() should back-fill them with the next offset prior to rollover.

testSizeLimit

public void testSizeLimit()

Test resize monitoring. Add a listener to an offsets writer, capture each resize, and refuse a resize when the number of ints exceeds 8K values. This will trigger an overflow, which will throw an exception which we then check for.