for (int index = 0; index < numSplits; index++) {
InMemInputSplit split = (InMemInputSplit) splits.get(index);
InMemRecordReader reader = new InMemRecordReader(split);
reader.initialize(split, null);
for (int tree = 0; tree < split.getNbTrees(); tree++) {
// reader.next() should return true until there is no tree left
assertEquals(tree < split.getNbTrees(), reader.nextKeyValue());
assertEquals(split.getFirstId() + tree, reader.getCurrentKey().get());