### Question:
Catalog { public TupleDesc getTupleDesc(int tableid) throws NoSuchElementException { return getDbFile(tableid).getTupleDesc(); } Catalog(); void addTable(DbFile file, String name, String pkeyField); void addTable(DbFile file, String name); void addTable(DbFile file); int getTableId(String name); TupleDesc getTupleDesc(int tableid); DbFile getDbFile(int tableid); String getPrimaryKey(int tableid); Iterator<Integer> tableIdIterator(); String getTableName(int id); void clear(); void loadSchema(String catalogFile);  }### Answer:
@Test public void getTupleDesc() throws Exception { TupleDesc expected = Utility.getTupleDesc(2); TupleDesc actual = Database.getCatalog().getTupleDesc(-1); assertEquals(expected.toString(), actual.toString()); }