/// <exception cref="System.IO.IOException"/>
public virtual InputSplit[] GetSplits(JobConf conf, int numSplits)
{
JobConf confCopy = new JobConf(conf);
IList <InputSplit> splits = new AList <InputSplit>();
IDictionary <Path, InputFormat> formatMap = MultipleInputs.GetInputFormatMap(conf);
IDictionary <Path, Type> mapperMap = MultipleInputs.GetMapperTypeMap(conf);
IDictionary <Type, IList <Path> > formatPaths = new Dictionary <Type, IList <Path> >();
// First, build a map of InputFormats to Paths
foreach (KeyValuePair <Path, InputFormat> entry in formatMap)
{
if (!formatPaths.Contains(entry.Value.GetType()))
{
formatPaths[entry.Value.GetType()] = new List <Path>();
}
formatPaths[entry.Value.GetType()].AddItem(entry.Key);
}
foreach (KeyValuePair <Type, IList <Path> > formatEntry in formatPaths)
{
Type formatClass = formatEntry.Key;
InputFormat format = (InputFormat)ReflectionUtils.NewInstance(formatClass, conf);
IList <Path> paths = formatEntry.Value;
IDictionary <Type, IList <Path> > mapperPaths = new Dictionary <Type, IList <Path> >();
// Now, for each set of paths that have a common InputFormat, build
// a map of Mappers to the paths they're used for
foreach (Path path in paths)
{
Type mapperClass = mapperMap[path];
if (!mapperPaths.Contains(mapperClass))
{
mapperPaths[mapperClass] = new List <Path>();
}
mapperPaths[mapperClass].AddItem(path);
}
// Now each set of paths that has a common InputFormat and Mapper can
// be added to the same job, and split together.
foreach (KeyValuePair <Type, IList <Path> > mapEntry in mapperPaths)
{
paths = mapEntry.Value;
Type mapperClass = mapEntry.Key;
if (mapperClass == null)
{
mapperClass = conf.GetMapperClass();
}
FileInputFormat.SetInputPaths(confCopy, Sharpen.Collections.ToArray(paths, new Path
[paths.Count]));
// Get splits for each input path and tag with InputFormat
// and Mapper types by wrapping in a TaggedInputSplit.
InputSplit[] pathSplits = format.GetSplits(confCopy, numSplits);
foreach (InputSplit pathSplit in pathSplits)
{
splits.AddItem(new TaggedInputSplit(pathSplit, conf, format.GetType(), mapperClass
));
}
}
}
return(Sharpen.Collections.ToArray(splits, new InputSplit[splits.Count]));
}
public virtual void TestAddInputPathWithFormat()
{
JobConf conf = new JobConf();
MultipleInputs.AddInputPath(conf, new Path("/foo"), typeof(TextInputFormat));
MultipleInputs.AddInputPath(conf, new Path("/bar"), typeof(KeyValueTextInputFormat
));
IDictionary <Path, InputFormat> inputs = MultipleInputs.GetInputFormatMap(conf);
NUnit.Framework.Assert.AreEqual(typeof(TextInputFormat), inputs[new Path("/foo")]
.GetType());
NUnit.Framework.Assert.AreEqual(typeof(KeyValueTextInputFormat), inputs[new Path(
"/bar")].GetType());
}
/// <exception cref="System.Exception"/>
public virtual void TestSplitting()
{
JobConf conf = new JobConf();
MiniDFSCluster dfs = null;
try
{
dfs = new MiniDFSCluster.Builder(conf).NumDataNodes(4).Racks(new string[] { "/rack0"
, "/rack0", "/rack1", "/rack1" }).Hosts(new string[] { "host0", "host1", "host2"
, "host3" }).Build();
FileSystem fs = dfs.GetFileSystem();
Path path = GetPath("/foo/bar", fs);
Path path2 = GetPath("/foo/baz", fs);
Path path3 = GetPath("/bar/bar", fs);
Path path4 = GetPath("/bar/baz", fs);
int numSplits = 100;
MultipleInputs.AddInputPath(conf, path, typeof(TextInputFormat), typeof(TestDelegatingInputFormat.MapClass
));
MultipleInputs.AddInputPath(conf, path2, typeof(TextInputFormat), typeof(TestDelegatingInputFormat.MapClass2
));
MultipleInputs.AddInputPath(conf, path3, typeof(KeyValueTextInputFormat), typeof(
TestDelegatingInputFormat.MapClass));
MultipleInputs.AddInputPath(conf, path4, typeof(TextInputFormat), typeof(TestDelegatingInputFormat.MapClass2
));
DelegatingInputFormat inFormat = new DelegatingInputFormat();
InputSplit[] splits = inFormat.GetSplits(conf, numSplits);
int[] bins = new int[3];
foreach (InputSplit split in splits)
{
NUnit.Framework.Assert.IsTrue(split is TaggedInputSplit);
TaggedInputSplit tis = (TaggedInputSplit)split;
int index = -1;
if (tis.GetInputFormatClass().Equals(typeof(KeyValueTextInputFormat)))
{
// path3
index = 0;
}
else
{
if (tis.GetMapperClass().Equals(typeof(TestDelegatingInputFormat.MapClass)))
{
// path
index = 1;
}
else
{
// path2 and path4
index = 2;
}
}
bins[index]++;
}
// Each bin is a unique combination of a Mapper and InputFormat, and
// DelegatingInputFormat should split each bin into numSplits splits,
// regardless of the number of paths that use that Mapper/InputFormat
foreach (int count in bins)
{
NUnit.Framework.Assert.AreEqual(numSplits, count);
}
NUnit.Framework.Assert.IsTrue(true);
}
finally
{
if (dfs != null)
{
dfs.Shutdown();
}
}
}
