/// <exception cref="System.Exception"/>
private void CheckCompression(bool compressMapOutputs, SequenceFile.CompressionType
redCompression, bool includeCombine)
{
JobConf conf = new JobConf(typeof(TestMapRed));
Path testdir = new Path(TestDir.GetAbsolutePath());
Path inDir = new Path(testdir, "in");
Path outDir = new Path(testdir, "out");
FileSystem fs = FileSystem.Get(conf);
fs.Delete(testdir, true);
FileInputFormat.SetInputPaths(conf, inDir);
FileOutputFormat.SetOutputPath(conf, outDir);
conf.SetMapperClass(typeof(TestMapRed.MyMap));
conf.SetReducerClass(typeof(TestMapRed.MyReduce));
conf.SetOutputKeyClass(typeof(Text));
conf.SetOutputValueClass(typeof(Text));
conf.SetOutputFormat(typeof(SequenceFileOutputFormat));
conf.Set(MRConfig.FrameworkName, MRConfig.LocalFrameworkName);
if (includeCombine)
{
conf.SetCombinerClass(typeof(IdentityReducer));
}
conf.SetCompressMapOutput(compressMapOutputs);
SequenceFileOutputFormat.SetOutputCompressionType(conf, redCompression);
try
{
if (!fs.Mkdirs(testdir))
{
throw new IOException("Mkdirs failed to create " + testdir.ToString());
}
if (!fs.Mkdirs(inDir))
{
throw new IOException("Mkdirs failed to create " + inDir.ToString());
}
Path inFile = new Path(inDir, "part0");
DataOutputStream f = fs.Create(inFile);
f.WriteBytes("Owen was here\n");
f.WriteBytes("Hadoop is fun\n");
f.WriteBytes("Is this done, yet?\n");
f.Close();
RunningJob rj = JobClient.RunJob(conf);
NUnit.Framework.Assert.IsTrue("job was complete", rj.IsComplete());
NUnit.Framework.Assert.IsTrue("job was successful", rj.IsSuccessful());
Path output = new Path(outDir, Task.GetOutputName(0));
NUnit.Framework.Assert.IsTrue("reduce output exists " + output, fs.Exists(output)
);
SequenceFile.Reader rdr = new SequenceFile.Reader(fs, output, conf);
NUnit.Framework.Assert.AreEqual("is reduce output compressed " + output, redCompression
!= SequenceFile.CompressionType.None, rdr.IsCompressed());
rdr.Close();
}
finally
{
fs.Delete(testdir, true);
}
}
/// <exception cref="System.IO.IOException"/>
public override RecordWriter <WritableComparable, Writable> GetRecordWriter(FileSystem
ignored, JobConf job, string name, Progressable progress)
{
// get the path of the temporary output file
Path file = FileOutputFormat.GetTaskOutputPath(job, name);
FileSystem fs = file.GetFileSystem(job);
CompressionCodec codec = null;
SequenceFile.CompressionType compressionType = SequenceFile.CompressionType.None;
if (GetCompressOutput(job))
{
// find the kind of compression to do
compressionType = SequenceFileOutputFormat.GetOutputCompressionType(job);
// find the right codec
Type codecClass = GetOutputCompressorClass(job, typeof(DefaultCodec));
codec = ReflectionUtils.NewInstance(codecClass, job);
}
// ignore the progress parameter, since MapFile is local
MapFile.Writer @out = new MapFile.Writer(job, fs, file.ToString(), job.GetOutputKeyClass
().AsSubclass <WritableComparable>(), job.GetOutputValueClass().AsSubclass <Writable
>(), compressionType, codec, progress);
return(new _RecordWriter_72(@out));
}