public ResultSet getPrimaryKeys()

in src/main/java/software/amazon/documentdb/jdbc/DocumentDbDatabaseMetaData.java [479:532]
37 lines of code
9 McCabe index (conditional complexity)

    public ResultSet getPrimaryKeys(final String catalog, final String schema,
            final String table) throws SQLException {
        // 1. TABLE_CAT String => table catalog (may be null)
        // 2. TABLE_SCHEM String => table schema (may be null)
        // 3. TABLE_NAME String => table name
        // 4. COLUMN_NAME String => column name
        // 5. KEY_SEQ short => sequence number within primary key( a value of 1 represents the first column of the primary key, a value of 2 would represent the second column within the primary key).
        // 6. PK_NAME String => primary key name (may be null)
        final List<List<Object>> metaData = new ArrayList<>();
        if (schema == null || properties.getDatabase().matches(convertPatternToRegex(schema))) {
            for (String tableName : databaseMetadata.getTableSchemaMap().keySet()) {
                if (table == null ||
                        tableName.matches(convertPatternToRegex(table))) {
                    final DocumentDbSchemaTable metadataTable = databaseMetadata
                            .getTableSchemaMap().get(tableName);
                    if (metadataTable == null) {
                        // This will occur if the table schema is deleted after retrieving the
                        // database schema.
                        throw SqlError.createSQLException(
                                LOGGER,
                                SqlState.DATA_EXCEPTION,
                                SqlError.INCONSISTENT_SCHEMA,
                                tableName);
                    }
                    for (DocumentDbSchemaColumn column : metadataTable.getColumnMap().values()) {
                        // 1. TABLE_CAT String => table catalog (may be null)
                        // 2. TABLE_SCHEM String => table schema (may be null)
                        // 3. TABLE_NAME String => table name
                        // 4. COLUMN_NAME String => column name
                        // 5. KEY_SEQ short => sequence number within primary key
                        //    (a value of 1 represents the first column of the primary key, a
                        //    value of 2 would represent the second column within the primary key).
                        // 6. PK_NAME String => primary key name (may be null)
                        if (column.isPrimaryKey()) {
                            final List<Object> row = new ArrayList<>(Arrays.asList(
                                    null, // TABLE_CAT
                                    properties.getDatabase(), // TABLE_SCHEM
                                    metadataTable.getSqlName(), // TABLE_NAME
                                    column.getSqlName(), // COLUMN_NAME
                                    column.getPrimaryKeyIndex(metadataTable).orElse(0), // KEY_SEQ
                                    null // PK_NAME
                            ));
                            metaData.add(row);
                        }
                    }
                }
            }
        }

        return new DocumentDbListResultSet(
                null,
                buildPrimaryKeysColumnMetaData(properties.getDatabase()),
                metaData);
    }