RelationManager { public DataWriter getTableDataWriter(String tableName) throws StorageException { if (isSystemCatalog(tableName)) { throw new StorageException("modify system catalog is not allowed"); } return new DataWriter(getTableDataStore(tableName), getTableAnalyzer(tableName)); } private  RelationManager(); static RelationManager getInstance(); boolean checkTableExistence(String tableName); void createTable(String tableName, Path indexDirectory, Schema schema, String luceneAnalyzerString); void deleteTable(String tableName); Tuple getTupleByID(String tableName, IDField idField); DataWriter getTableDataWriter(String tableName); DataReader getTableDataReader(String tableName, Query tupleQuery); DataStore getTableDataStore(String tableName); String getTableDirectory(String tableName); Schema getTableSchema(String tableName); String getTableAnalyzerString(String tableName); Analyzer getTableAnalyzer(String tableName); List<TableMetadata> getMetaData();  }
@Test(expected = StorageException.class) public void test13() throws Exception { relationManager.getTableDataWriter(CatalogConstants.TABLE_CATALOG); }
@Test(expected = StorageException.class) public void test14() throws Exception { relationManager.getTableDataWriter(CatalogConstants.SCHEMA_CATALOG); }