question: private String nameWithoutTaskID ( String objectName ) { int index = objectName . indexOf ( "-" + HADOOP_ATTEMPT ) ; if ( index > 0 ) { String attempt = objectName . substring ( objectName . lastIndexOf ( "-" ) + 1 ) ; try { TaskAttemptID . forName ( attempt ) ; return objectName . substring ( 0 , index ) ; } catch ( IllegalArgumentException e ) { return objectName ; } } return objectName ; }
target:  Accepts any object name. If object name is of the form a/b/c/m.data/part-r-00000-48ae3461-203f-4dd3-b141-a45426e2d26c .csv-attempt_20160317132a_wrong_0000_m_000000_1 Then a/b/c/m.data/part-r-00000-48ae3461-203f-4dd3-b141-a45426e2d26c.csv is returned. Perform test that attempt_20160317132a_wrong_0000_m_000000_1 is valid task id identifier