Examples with JDBCProvider eu.esdihumboldt.hale.io.jdbc.JDBCProvider used on opensource projects

Example 1 with JDBCProvider

use of eu.esdihumboldt.hale.io.jdbc.JDBCProvider in project hale by halestudio.

the class SQLSchemaPage method updateState.

private boolean updateState(boolean runQuery) {
    boolean typeValid = false;
    boolean sqlValid = false;
    String error = null;
    String message = null;
    if (typeName != null) {
        // check type name
        String type = typeName.getText();
        typeValid = type != null && !type.isEmpty();
        if (typeValid) {
            // check if the name already exists in the source schema
            SchemaService schemas = HaleUI.getServiceProvider().getService(SchemaService.class);
            if (schemas != null) {
                TypeDefinition existing = schemas.getSchemas(SchemaSpaceID.SOURCE).getType(new QName(SQLSchemaReader.NAMESPACE, type));
                if (existing != null) {
                    typeValid = false;
                    error = "An SQL query with this name already exists";
                }
            }
        // also test for specific characters?
        }
    }
    if (sqlQuery != null) {
        // check SQL query
        String sql = sqlQuery.getText();
        sqlValid = sql != null && !sql.isEmpty();
        if (sqlValid) {
            String processedQuery;
            try {
                processedQuery = JDBCUtil.replaceVariables(sql, HaleUI.getServiceProvider());
            } catch (Exception e) {
                error = e.getLocalizedMessage();
                sqlValid = false;
                processedQuery = null;
            }
            // check if processed SQL query can be executed
            if (runQuery && processedQuery != null) {
                ImportProvider provider = getWizard().getProvider();
                if (provider != null && provider instanceof JDBCProvider) {
                    Connection connection = null;
                    try {
                        try {
                            connection = ((JDBCProvider) provider).getConnection();
                        } catch (SQLException e) {
                            sqlValid = false;
                            error = "Could not establish database connection: " + e.getLocalizedMessage();
                        }
                        if (connection != null) {
                            try {
                                Statement statement = JDBCUtil.createReadStatement(connection, 1);
                                try {
                                    ResultSet result = statement.executeQuery(processedQuery);
                                    int columnCount = result.getMetaData().getColumnCount();
                                    if (columnCount <= 0) {
                                        sqlValid = false;
                                        error = "Query result does not have any columns";
                                    } else {
                                        if (columnCount == 1) {
                                            message = "Successfully tested query. It yields a result with a single column.";
                                        } else {
                                            message = MessageFormat.format("Successfully tested query. It yields a result with {0} columns.", columnCount);
                                        }
                                    }
                                } catch (SQLException e) {
                                    sqlValid = false;
                                    error = "Error querying database: " + e.getMessage();
                                } finally {
                                    statement.close();
                                }
                            } catch (SQLException e) {
                                sqlValid = false;
                                error = "Could not create database statement: " + e.getMessage();
                            }
                        }
                    } finally {
                        if (connection != null) {
                            try {
                                connection.close();
                            } catch (SQLException e) {
                            // ignore
                            }
                        }
                    }
                }
            }
        }
    }
    boolean complete = typeValid && sqlValid;
    if (complete) {
        error = null;
    } else if (!typeValid && error == null) {
        error = "Please provide a name for the query";
    } else if (error == null) {
        error = "Please specify the SQL query to use";
    }
    setMessage(message);
    setErrorMessage(error);
    setPageComplete(complete);
    return complete;
}