diff options
Diffstat (limited to 'src/uk/org/ury/database/DatabaseDriver.java')
| -rw-r--r-- | src/uk/org/ury/database/DatabaseDriver.java | 298 |
1 files changed, 146 insertions, 152 deletions
diff --git a/src/uk/org/ury/database/DatabaseDriver.java b/src/uk/org/ury/database/DatabaseDriver.java index 7c71827..e48b0a1 100644 --- a/src/uk/org/ury/database/DatabaseDriver.java +++ b/src/uk/org/ury/database/DatabaseDriver.java @@ -11,162 +11,156 @@ import uk.org.ury.config.ConfigReader; import uk.org.ury.database.exceptions.ConnectionFailureException; import uk.org.ury.database.exceptions.MissingCredentialsException; - /** - * A database connection manager that connects to the URY databases - * using suitably privileged accounts, and handles the processing - * of SQL queries. - * + * A database connection manager that connects to the URY databases using + * suitably privileged accounts, and handles the processing of SQL queries. + * * @author Matt Windsor * @author Nathan Lasseter - * + * */ +public class DatabaseDriver { + /* The JDBC path used to connect to the URY database. */ + private String DATABASE_PATH = "jdbc:postgresql://"; + + /* The database connection. */ + private Connection conn; + + /** + * Construct a new DatabaseDriver with the given user class. + * + * @param config + * The config with login details. + * + * @param type + * The user class to log in to the database with. + * + * @throws IllegalArgumentException + * if the user class is not supported (this should not happen). + * + * @throws MissingCredentialsException + * if the user class login credentials could not be loaded. + * + * @throws ConnectionFailureException + * if the database backend failed to connect to the database + * server. + */ + public DatabaseDriver(ConfigReader config, UserClass type) + throws MissingCredentialsException, ConnectionFailureException { + try { + connect(config, type); + } catch (SQLException e) { + throw new ConnectionFailureException(e.getMessage()); + } + + } + + /** + * Connect to the URY database. + * + * @param config + * The config to use for the connection. + * @param type + * The access level of the connection + * + * @throws SQLException + * if the database connection failed. + */ + private void connect(ConfigReader config, UserClass type) + throws SQLException { + if (config == null) + throw new IllegalArgumentException("Supplied null config."); + + if (config.getDatabase().getHost() == null) + throw new IllegalArgumentException("config has no associated host."); + + if (config.getDatabase().getDb() == null) + throw new IllegalArgumentException( + "config has no associated database."); + + DATABASE_PATH = DATABASE_PATH + config.getDatabase().getHost() + "/" + + config.getDatabase().getDb(); + + if (type == UserClass.READ_ONLY) { + if (config.getRoAuth().getUser() == null) + throw new IllegalArgumentException( + "config has no associated username."); + if (config.getRoAuth().getPass() == null) + throw new IllegalArgumentException( + "config has no associated password."); + conn = DriverManager.getConnection(DATABASE_PATH, config + .getRoAuth().getUser(), config.getRoAuth().getPass()); + } else if (type == UserClass.READ_WRITE) { + if (config.getRwAuth().getUser() == null) + throw new IllegalArgumentException( + "config has no associated username."); + if (config.getRwAuth().getPass() == null) + throw new IllegalArgumentException( + "config has no associated password."); + conn = DriverManager.getConnection(DATABASE_PATH, config + .getRwAuth().getUser(), config.getRwAuth().getPass()); + } + } + + /** + * Execute an unprepared SQL statement with no arguments. + * + * @param sql + * The SQL statement to execute. + * @param fetchSize + * The maximum number of query rows to return. + * + * @return the JDBC results set. + * + * @throws SQLException + * if a SQL error occurs. + */ + public ResultSet executeQuery(String sql, int fetchSize) + throws SQLException { + Statement st = conn.createStatement(); + st.setFetchSize(fetchSize); + + return st.executeQuery(sql); + } + + /** + * Perform a SQL statement with arguments. + * + * This accepts an array of parameter objects, which must each either be + * String or Integer objects. The objects will be used sequentially to fill + * in '?' placeholders in the query text. + * + * @param sql + * The SQL statement to execute. + * @param params + * A list of parameter objects. + * @param fetchSize + * The maximum number of query rows to return. + * + * @return the set of results from the query. + * + * @throws IllegalArgumentException + * if any of the parameters is unsupported by the database as a + * statement parameter. + * + * @throws SQLException + * if a SQL error occurs. + */ + public ResultSet executeQuery(String sql, Object[] params, int fetchSize) + throws SQLException { + PreparedStatement st = conn.prepareStatement(sql); + + st.setFetchSize(fetchSize); + + for (int i = 0; i < params.length; i++) + if (params[i] instanceof String) + st.setString(i + 1, (String) params[i]); + else if (params[i] instanceof Integer) + st.setInt(i + 1, (Integer) params[i]); + else + throw new IllegalArgumentException("Unsupported parameter #" + + (i + 1)); -public class DatabaseDriver -{ - /* The JDBC path used to connect to the URY database. */ - private String DATABASE_PATH = "jdbc:postgresql://"; - - /* The database connection. */ - private Connection conn; - - - /** - * Construct a new DatabaseDriver with the given user class. - * - * @param config The config with login details. - * - * @param type The user class to log in to the database with. - * - * @throws IllegalArgumentException if the user class is - * not supported (this should not happen). - * - * @throws MissingCredentialsException if the user class - * login credentials could not be loaded. - * - * @throws ConnectionFailureException if the database - * backend failed to connect to the database - * server. - */ - - public - DatabaseDriver (ConfigReader config, UserClass type) - throws MissingCredentialsException, ConnectionFailureException - { - try - { - connect (config, type); - } - catch (SQLException e) - { - throw new ConnectionFailureException (e.getMessage ()); - } - - } - - - /** - * Connect to the URY database. - * - * @param config The config to use for the connection. - * @param type The access level of the connection - * - * @throws SQLException if the database connection failed. - */ - - private void - connect (ConfigReader config, UserClass type) - throws SQLException - { - if (config == null) - throw new IllegalArgumentException ("Supplied null config."); - - if (config.getDatabase().getHost() == null) - throw new IllegalArgumentException ("config has no associated host."); - - if (config.getDatabase().getDb() == null) - throw new IllegalArgumentException ("config has no associated database."); - - DATABASE_PATH = DATABASE_PATH + config.getDatabase().getHost() + "/" + config.getDatabase().getDb(); - - if(type == UserClass.READ_ONLY) { - if(config.getRoAuth().getUser() == null) - throw new IllegalArgumentException ("config has no associated username."); - if(config.getRoAuth().getPass() == null) - throw new IllegalArgumentException ("config has no associated password."); - conn = DriverManager.getConnection (DATABASE_PATH, - config.getRoAuth().getUser(), - config.getRoAuth().getPass()); - } else if(type == UserClass.READ_WRITE) { - if(config.getRwAuth().getUser() == null) - throw new IllegalArgumentException ("config has no associated username."); - if(config.getRwAuth().getPass() == null) - throw new IllegalArgumentException ("config has no associated password."); - conn = DriverManager.getConnection (DATABASE_PATH, - config.getRwAuth().getUser(), - config.getRwAuth().getPass()); + return st.executeQuery(); } - } - - - /** - * Execute an unprepared SQL statement with no arguments. - * - * @param sql The SQL statement to execute. - * @param fetchSize The maximum number of query rows to return. - * - * @return the JDBC results set. - * - * @throws SQLException if a SQL error occurs. - */ - - public ResultSet - executeQuery (String sql, int fetchSize) - throws SQLException - { - Statement st = conn.createStatement (); - st.setFetchSize (fetchSize); - - return st.executeQuery (sql); - } - - - /** - * Perform a SQL statement with arguments. - * - * This accepts an array of parameter objects, which must each - * either be String or Integer objects. The objects will be used - * sequentially to fill in '?' placeholders in the query text. - * - * @param sql The SQL statement to execute. - * @param params A list of parameter objects. - * @param fetchSize The maximum number of query rows to return. - * - * @return the set of results from the query. - * - * @throws IllegalArgumentException if any of the - * parameters is unsupported by the database as - * a statement parameter. - * - * @throws SQLException if a SQL error occurs. - */ - - public ResultSet - executeQuery (String sql, Object[] params, int fetchSize) - throws SQLException - { - PreparedStatement st = conn.prepareStatement (sql); - - st.setFetchSize (50); - - for (int i = 0; i < params.length; i++) - if (params[i] instanceof String) - st.setString (i + 1, (String) params[i]); - else if (params[i] instanceof Integer) - st.setInt (i + 1, (Integer) params[i]); - else - throw new IllegalArgumentException ("Unsupported parameter #" + (i + 1)); - - return st.executeQuery (); - } } |