### Question:
MultiplexingJdbcMetadataHandler extends JdbcMetadataHandler { @Override public Schema getPartitionSchema(final String catalogName) { validateMultiplexer(catalogName); return this.metadataHandlerMap.get(catalogName).getPartitionSchema(catalogName); } @VisibleForTesting  MultiplexingJdbcMetadataHandler(final AWSSecretsManager secretsManager, final AmazonAthena athena, final JdbcConnectionFactory jdbcConnectionFactory,
            final Map<String, JdbcMetadataHandler> metadataHandlerMap, final DatabaseConnectionConfig databaseConnectionConfig);  MultiplexingJdbcMetadataHandler(); @Override Schema getPartitionSchema(final String catalogName); @Override ListSchemasResponse doListSchemaNames(BlockAllocator blockAllocator, ListSchemasRequest listSchemasRequest); @Override ListTablesResponse doListTables(BlockAllocator blockAllocator, ListTablesRequest listTablesRequest); @Override GetTableResponse doGetTable(BlockAllocator blockAllocator, GetTableRequest getTableRequest); @Override void getPartitions(final BlockWriter blockWriter, final GetTableLayoutRequest getTableLayoutRequest, QueryStatusChecker queryStatusChecker); @Override GetTableLayoutResponse doGetTableLayout(BlockAllocator blockAllocator, GetTableLayoutRequest getTableLayoutRequest); @Override GetSplitsResponse doGetSplits(
            final BlockAllocator blockAllocator, final GetSplitsRequest getSplitsRequest);  }### Answer:
@Test public void getPartitionSchema() { this.jdbcMetadataHandler.getPartitionSchema("mysql"); Mockito.verify(this.mySqlMetadataHandler, Mockito.times(1)).getPartitionSchema(Mockito.eq("mysql")); }
@Test(expected = RuntimeException.class) public void getPartitionSchemaForUnsupportedCatalog() { this.jdbcMetadataHandler.getPartitionSchema("unsupportedCatalog"); }