net.sf.farrago.namespace
Interface FarragoMedNameDirectory

All Known Implementing Classes:

FlatFileNameDirectory, MedAbstractNameDirectory, MedJdbcNameDirectory, MedMdrNameDirectory, MedMockNameDirectory

public interface FarragoMedNameDirectory

FarragoMedNameDirectory defines a virtual hierarchical namespace interface in which to look up tables, routines, other namespaces, etc.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/namespace/FarragoMedNameDirectory.java#12 $

Author:

John V. Sichi

Method Summary

FarragoMedColumnSet	lookupColumnSet(FarragoTypeFactory typeFactory, String foreignName, String[] localName) Looks up a FarragoMedColumnSet by name.
FarragoMedNameDirectory	lookupSubdirectory(String foreignName) Looks up an immediate subdirectory by name.
FemBaseColumnSet	newImportedColumnSet(FarragoRepos repos, String tableName) Creates a new instance of FemBaseColumnSet in the catalog to represent an imported table.
boolean	queryMetadata(FarragoMedMetadataQuery query, FarragoMedMetadataSink sink) Executes a query against the metadata contained by this directory.

Method Detail

lookupColumnSet

FarragoMedColumnSet lookupColumnSet(FarragoTypeFactory typeFactory,
                                    String foreignName,
                                    String[] localName)
                                    throws SQLException

Looks up a FarragoMedColumnSet by name. This method supports Farrago's capability to reference a foreign table directly without having to create local metadata about it.

Parameters:

typeFactory - FarragoTypeFactory to use for defining types

foreignName - simple name of foreign ColumnSet to lookup as a direct child of this directory

localName - compound identifier by which FarragoMedColumnSet will be referenced locally

Returns:

FarragoMedColumnSet, or null if none found

Throws:

SQLException - if metadata access is unsuccessful

lookupSubdirectory

FarragoMedNameDirectory lookupSubdirectory(String foreignName)
                                           throws SQLException

Looks up an immediate subdirectory by name.

Parameters:

foreignName - identifier for subdirectory

Returns:

subdirectory, or null if none found

Throws:

SQLException - if metadata access is unsuccessful

queryMetadata

boolean queryMetadata(FarragoMedMetadataQuery query,
                      FarragoMedMetadataSink sink)
                      throws SQLException

Executes a query against the metadata contained by this directory. This method supports the SQL/MED IMPORT FOREIGN SCHEMA statement, and general metadata browsing.

NOTE: the supplied sink may be used to implement passive aborts by throwing an unchecked exception when an abort request is detected.

Parameters:

query - the query to execute

sink - target which receives the query results

Returns:

true if the query executed successfully; false if the requested query type was not supported

Throws:

SQLException - if metadata access is unsuccessful (but not if query is unsupported)

newImportedColumnSet

FemBaseColumnSet newImportedColumnSet(FarragoRepos repos,
                                      String tableName)

Creates a new instance of FemBaseColumnSet in the catalog to represent an imported table.

Parameters:

repos - repository storing catalog

tableName - name of imported table

Returns:

new object in catalog