question: cleanup after the test concode_field_sep MiniDFSCluster cluster concode_elem_sep NamenodeProtocols nnRpc concode_elem_sep Configuration conf concode_field_sep void testDeleteSnapshotWhenSnapshotNameIsEmpty concode_elem_sep void setup
target: void function ( ) { if ( cluster != null ) { cluster . shutdown ( ) ; cluster = null ; } }