ensures that the given object reference is not null . upon violation , a nullpointerexception with no message is thrown . concode_field_sep PlaceHolder placeHolder concode_field_sep void checkState concode_elem_sep void checkState concode_elem_sep void checkState concode_elem_sep String format concode_elem_sep void checkArgument concode_elem_sep void checkArgument concode_elem_sep void checkArgument concode_elem_sep void checkElementIndex concode_elem_sep void checkElementIndex
T function ( T arg0 ) { if ( arg0 == null ) { throw new NullPointerException ( ) ; } return arg0 ; }