TableDescriptors htd = Mockito.mock(TableDescriptors.class);
Object orizinalState = Whitebox.getInternalState(regionServer,"tableDescriptors");
Whitebox.setInternalState(regionServer, "tableDescriptors", htd);
Mockito.doThrow(new IOException()).when(htd).get((byte[]) Mockito.any());
try {
regionServer.openRegion(REGIONINFO);
fail("It should throw IOException ");
} catch (IOException e) {
}
Whitebox.setInternalState(regionServer, "tableDescriptors", orizinalState);
assertFalse("Region should not be in RIT",