// hflush file
AppendTestUtil.LOG.info("hflush");
stm.hflush();
// check visible length
final HdfsDataInputStream in = (HdfsDataInputStream)dfs.open(filePath);
Assert.assertEquals(size, in.getVisibleLength());
in.close();
if (doRename) {
fileStr += ".renamed";
Path renamedPath = new Path(fileStr);
assertTrue(dfs.rename(filePath, renamedPath));