/// <exception cref="System.Exception"/>
private void CheckMembershipVaryingSizedKeys(string name, IList <Text> keys)
{
FileSystem fs = FileSystem.GetLocal(conf);
Path qualifiedDirName = fs.MakeQualified(TestDir);
BloomMapFile.Writer writer = null;
BloomMapFile.Reader reader = null;
try
{
writer = new BloomMapFile.Writer(conf, fs, qualifiedDirName.ToString(), typeof(Text
), typeof(NullWritable));
foreach (Text key in keys)
{
writer.Append(key, NullWritable.Get());
}
writer.Close();
// will check for membership in opposite order of how keys were inserted
reader = new BloomMapFile.Reader(fs, qualifiedDirName.ToString(), conf);
Collections.Reverse(keys);
foreach (Text key_1 in keys)
{
Assert.True("False negative for existing key " + key_1, reader.
ProbablyHasKey(key_1));
}
reader.Close();
fs.Delete(qualifiedDirName, true);
}
finally
{
IOUtils.Cleanup(null, writer, reader);
}
}
/// <exception cref="System.Exception"/>
public virtual void TestMembershipTest()
{
// write the file
FileSystem fs = FileSystem.GetLocal(conf);
Path qualifiedDirName = fs.MakeQualified(TestDir);
conf.SetInt("io.mapfile.bloom.size", 2048);
BloomMapFile.Writer writer = null;
BloomMapFile.Reader reader = null;
try
{
writer = new BloomMapFile.Writer(conf, fs, qualifiedDirName.ToString(), typeof(IntWritable
), typeof(Text));
IntWritable key = new IntWritable();
Text value = new Text();
for (int i = 0; i < 2000; i += 2)
{
key.Set(i);
value.Set("00" + i);
writer.Append(key, value);
}
writer.Close();
reader = new BloomMapFile.Reader(fs, qualifiedDirName.ToString(), conf);
// check false positives rate
int falsePos = 0;
int falseNeg = 0;
for (int i_1 = 0; i_1 < 2000; i_1++)
{
key.Set(i_1);
bool exists = reader.ProbablyHasKey(key);
if (i_1 % 2 == 0)
{
if (!exists)
{
falseNeg++;
}
}
else
{
if (exists)
{
falsePos++;
}
}
}
reader.Close();
fs.Delete(qualifiedDirName, true);
System.Console.Out.WriteLine("False negatives: " + falseNeg);
Assert.Equal(0, falseNeg);
System.Console.Out.WriteLine("False positives: " + falsePos);
Assert.True(falsePos < 2);
}
finally
{
IOUtils.Cleanup(null, writer, reader);
}
}