com.bigdata.io

Class TestLongPacker

java.lang.Object

junit.framework.Assert

junit.framework.TestCase

com.bigdata.io.TestLongPacker

All Implemented Interfaces:

junit.framework.Test

public class TestLongPacker
extends junit.framework.TestCase

Test suite for packing and unpacking unsigned long integers using the DataInputBuffer and the ByteArrayBuffer.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
static long	SIGN_MASK

Constructor Summary

Constructors

Constructor and Description
TestLongPacker()
TestLongPacker(String name)

Method Summary

Methods

Modifier and Type	Method and Description
static void	assertEquals(String msg, byte[] expected, byte[] actual)
void	doPackTest(long v, byte[] expected)
void	doStressTest(int ntrials, com.bigdata.io.TestLongPacker.LongGenerator g) Run a stress test.
void	doUnpackTest(long expected, byte[] packed) Unpacks a long.
int	getNBytes(int firstByte) Given the first byte of a packed long value, return the #of bytes into which that value was packed (including this one).
void	test_compatiblity_DataOutputBuffer_LongPacker() This test packs the data using a DataOutputBuffer and unpacks it using the LongPacker.
void	test_compatiblity_LongPacker_DataInputBuffer() This test packs the data using the LongPacker and unpacks it using a DataInputBuffer.
void	test_getNibbleLength()
void	testHighBit()
void	testNBytes()
void	testPack()
void	testStressRandom() Run a large #of random pack/unpack operations to sample the space while showing correctness on those samples.
void	testStressRandomNonNegativeLeadingZeros() Run a large #of random pack/unpack operations to sample the space while showing correctness on those samples.
void	testStressSequence() Run a large #of pack/unpack operations on a sequence of long values to demonstrate correctness in that sequence.
void	testUnpack()

Methods inherited from class junit.framework.TestCase

assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertFalse, assertFalse, assertNotNull, assertNotNull, assertNotSame, assertNotSame, assertNull, assertNull, assertSame, assertSame, assertTrue, assertTrue, countTestCases, createResult, fail, fail, failNotEquals, failNotSame, failSame, format, getName, run, run, runBare, runTest, setName, setUp, tearDown, toString

Methods inherited from class java.lang.Object

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

Field Detail

SIGN_MASK

public static final long SIGN_MASK

See Also:

Constant Field Values

Constructor Detail

TestLongPacker

public TestLongPacker()

TestLongPacker

public TestLongPacker(String name)

Parameters:

name -

Method Detail

doUnpackTest

public void doUnpackTest(long expected,
                byte[] packed)
                  throws IOException

Unpacks a long.

Parameters:

expected - The expected long value.

packed - The packed byte[].

Throws:

IOException - If there was not enough data.

junit.framework.AssertionFailedError - If there is too much data.

getNBytes

public int getNBytes(int firstByte)

Given the first byte of a packed long value, return the #of bytes into which that value was packed (including this one).

Parameters:

firstByte - The first byte.

Returns:

The #of bytes. This is in the range [1:8] inclusive.

testNBytes

public void testNBytes()

testUnpack

public void testUnpack()
                throws IOException

Throws:

IOException

doPackTest

public void doPackTest(long v,
              byte[] expected)
                throws IOException

Throws:

IOException

test_getNibbleLength

public void test_getNibbleLength()

testPack

public void testPack()
              throws IOException

Throws:

IOException

testHighBit

public void testHighBit()

testStressSequence

public void testStressSequence()
                        throws IOException

Run a large #of pack/unpack operations on a sequence of long values to demonstrate correctness in that sequence. The sequence is the long values from -1 to 1M by one (dense coverage).

Throws:

IOException

testStressRandom

public void testStressRandom()
                      throws IOException

Run a large #of random pack/unpack operations to sample the space while showing correctness on those samples. The amount of compression due to packing for this test is very small since all bits are equally likely to be non-zero, so the #of bytes required on average to pack a long value is 8.

Throws:

IOException

testStressRandomNonNegativeLeadingZeros

public void testStressRandomNonNegativeLeadingZeros()
                                             throws IOException

Run a large #of random pack/unpack operations to sample the space while showing correctness on those samples. The samples are drawn from the non-negative longs and have a random number of leading bits set to zero. Since the values are non-negative there will always be at least one bit (the high bit) that is zero.

Throws:

IOException

doStressTest

public void doStressTest(int ntrials,
                com.bigdata.io.TestLongPacker.LongGenerator g)
                  throws IOException

Run a stress test. Writes some information of possible interest onto System.err.

Parameters:

ntrials - #of trials.

g - Generator for the long values.

Throws:

IOException

assertEquals

public static void assertEquals(String msg,
                byte[] expected,
                byte[] actual)

test_compatiblity_LongPacker_DataInputBuffer

public void test_compatiblity_LongPacker_DataInputBuffer()
                                                  throws IOException

This test packs the data using the LongPacker and unpacks it using a DataInputBuffer.

Throws:

IOException

test_compatiblity_DataOutputBuffer_LongPacker

public void test_compatiblity_DataOutputBuffer_LongPacker()
                                                   throws IOException

This test packs the data using a DataOutputBuffer and unpacks it using the LongPacker.

Throws:

IOException