question: protected static Object [ ] [ ] parseKey ( Connection conn , String key ) { ArrayList < String > columns = New . arrayList ( ) ; ArrayList < String > data = New . arrayList ( ) ; JdbcConnection c = ( JdbcConnection ) conn ; Session session = ( Session ) c . getSession ( ) ; Parser p = new Parser ( session ) ; Expression expr = p . parseExpression ( key ) ; addColumnData ( columns , data , expr ) ; Object [ ] col = new Object [ columns . size ( ) ] ; columns . toArray ( col ) ; Object [ ] dat = new Object [ columns . size ( ) ] ; data . toArray ( dat ) ; Object [ ] [ ] columnData = { col , dat } ; return columnData ; }
target:  Parse a primary key condition into the primary key columns.