Module org.hsqldb
Package org.hsqldb.jdbc

Class JDBCDriver

  • All Implemented Interfaces:
    java.sql.Driver
    public class JDBCDriver
extends java.lang.Object
implements java.sql.Driver
    The interface that every driver class must implement.

    The Java SQL framework allows for multiple database drivers.

    Each driver should supply a class that implements the Driver interface.

    The DriverManager will try to load as many drivers as it can find and then for any given connection request, it will ask each driver in turn to try to connect to the target URL.

    It is strongly recommended that each Driver class should be small and standalone so that the Driver class can be loaded and queried without bringing in vast quantities of supporting code.

    When a Driver class is loaded, it should create an instance of itself and register it with the DriverManager. This means that a user can load and register a driver by calling:

    Class.forName("foo.bah.Driver")

    A JDBC driver may create a DriverAction implementation in order to receive notifications when DriverManager.deregisterDriver(java.sql.Driver) has been called.

    HSQLDB-Specific Information:

    When the HSQL Database Engine Driver class is loaded, it creates an instance of itself and register it with the DriverManager. This means that a user can load and register the HSQL Database Engine driver by calling: 
      Class.forName("org.hsqldb.jdbc.JDBCDriver")
    For detailed information about how to obtain HSQLDB JDBC Connections, please see JDBCConnection.
    JDBC 4.0 notes:

    Starting with JDBC 4.0 (JDK 1.6), the DriverManager methods getConnection and getDrivers have been enhanced to support the Java Standard Edition Service Provider mechanism. When built under a Java runtime that supports JDBC 4.0, HSQLDB distribution jars containing the Driver implementation also include the file META-INF/services/java.sql.Driver. This file contains the fully qualified class name ('org.hsqldb.jdbc.JDBCDriver') of the HSQLDB implementation of java.sql.Driver.

    Hence, under JDBC 4.0 or greater, applications no longer need to explicitly load the HSQLDB JDBC driver using Class.forName(). Of course, existing programs which do load JDBC drivers using Class.forName() will continue to work without modification.

    JDBC 4.2 methods added in Java 8 are generally supported.

    Since:
    JDK 1.1, HSQLDB 1.9.0
    Author:
    Campbell Burnet (campbell-burnet@users dot sourceforge.net), Fred Toussi (fredt@users dot sourceforge.net)
    See Also:
    DriverManager, Connection, DriverAction

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static JDBCDriver driverInstance  
      java.lang.ThreadLocal<JDBCConnection> threadConnection
      As a separate instance of this class is registered with DriverManager for each class loader, the threadConnection is not declared as static.

    • Constructor Summary

      Constructors 
      Constructor Description
      JDBCDriver()
      Default constructor

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean acceptsURL​(java.lang.String url)
      Retrieves whether the driver thinks that it can open a connection to the given URL.
      java.sql.Connection connect​(java.lang.String url, java.util.Properties info)
      Attempts to make a database connection to the given URL.
      static java.sql.Connection getConnection​(java.lang.String url, java.util.Properties info)
      The static equivalent of the connect(String,Properties) method.
      int getMajorVersion()
      Retrieves the driver's major version number.
      int getMinorVersion()
      Gets the driver's minor version number.
      java.util.logging.Logger getParentLogger()
      Return the parent Logger of all the Loggers used by this driver.
      java.sql.DriverPropertyInfo[] getPropertyInfo​(java.lang.String url, java.util.Properties info)
      Gets information about the possible properties for this driver.
      boolean jdbcCompliant()
      Reports whether this driver is a genuine JDBC Compliant driver.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • driverInstance

        public static final JDBCDriver driverInstance

      • threadConnection

        public final java.lang.ThreadLocal<JDBCConnection> threadConnection
        As a separate instance of this class is registered with DriverManager for each class loader, the threadConnection is not declared as static. The registered instance is kept to allow access to its threadConnection.

    • Constructor Detail

      • JDBCDriver

        public JDBCDriver()
        Default constructor

    • Method Detail

      • connect

        public java.sql.Connection connect​(java.lang.String url,
                                   java.util.Properties info)
                            throws java.sql.SQLException
        Attempts to make a database connection to the given URL. The driver should return "null" if it realizes it is the wrong kind of driver to connect to the given URL. This will be common, as when the JDBC driver manager is asked to connect to a given URL it passes the URL to each loaded driver in turn.

        The driver should throw an SQLException if it is the right driver to connect to the given URL but has trouble connecting to the database.

        The java.util.Properties argument can be used to pass arbitrary string tag/value pairs as connection arguments. Normally at least "user" and "password" properties should be included in the Properties object.

        Note: If a property is specified as part of the url and is also specified in the Properties object, it is implementation-defined as to which value will take precedence. For maximum portability, an application should only specify a property once.

        HSQLDB-Specific Information:

        For the HSQL Database Engine, at least "user" and "password" properties should be included in the Properties.

        From version 1.7.1, two optional properties are supported:

        • get_column_name (default true) - if set to false, a ResultSetMetaData.getColumnName() call will return the user defined label (getColumnLabel()) instead of the column name.
          This property is available in order to achieve compatibility with certain non-HSQLDB JDBC driver implementations.
        • strict_md if set to true, some ResultSetMetaData methods return more strict values for compatibility reasons.

        From version 1.8.0.x, strict_md is deprecated (ignored) because metadata reporting is always strict (JDBC-compliant), and three new optional properties are supported:

        • ifexits (default false) - when true, an exception is raised when attempting to connect to an in-process file: or mem: scheme database instance if it has not yet been created. When false, an in-process file: or mem: scheme database instance is created automatically if it has not yet been created. This property does not apply to requests for network or res: (i.e. files_in_jar) scheme connections.
        • shutdown (default false) - when true, the the target database mimics the behaviour of 1.7.1 and older versions. When the last connection to a database is closed, the database is automatically shut down. The property takes effect only when the first connection is made to the database. This means the connection that opens the database. It has no effect if used with subsequent, simultaneous connections.
          This command has two uses. One is for test suites, where connections to the database are made from one JVM context, immediately followed by another context. The other use is for applications where it is not easy to configure the environment to shutdown the database. Examples reported by users include web application servers, where the closing of the last connection coincides with the web application being shut down.
        • default_schema - backwards compatibility feature. To be used for clients written before HSQLDB schema support. Denotes whether to use the default schema when a schema qualifier is not included in a database object's SQL identifier character sequence. Also affects the semantics of DatabaseMetaData calls that supply null-valued schemaNamePattern parameter values.
        Specified by:
        connect in interface java.sql.Driver
        Parameters:
        url - the URL of the database to which to connect
        info - a list of arbitrary string tag/value pairs as connection arguments. Normally at least a "user" and "password" property should be included.
        Returns:
        a Connection object that represents a connection to the URL
        Throws:
        java.sql.SQLException - if a database access error occurs or the url is null

      • getConnection

        public static java.sql.Connection getConnection​(java.lang.String url,
                                                java.util.Properties info)
                                         throws java.sql.SQLException
        The static equivalent of the connect(String,Properties) method.
        Parameters:
        url - the URL of the database to which to connect
        info - a list of arbitrary string tag/value pairs as connection arguments including at least at a "user" and a "password" property
        Returns:
        a Connection object that represents a connection to the URL
        Throws:
        java.sql.SQLException - if a database access error occurs

      • acceptsURL

        public boolean acceptsURL​(java.lang.String url)
        Retrieves whether the driver thinks that it can open a connection to the given URL. Typically drivers will return true if they understand the sub-protocol specified in the URL and false if they do not.
        Specified by:
        acceptsURL in interface java.sql.Driver
        Parameters:
        url - the URL of the database
        Returns:
        true if this driver understands the given URL; false otherwise null

      • getPropertyInfo

        public java.sql.DriverPropertyInfo[] getPropertyInfo​(java.lang.String url,
                                                     java.util.Properties info)
        Gets information about the possible properties for this driver.

        The getPropertyInfo method is intended to allow a generic GUI tool to discover what properties it should prompt a human for in order to get enough information to connect to a database. Note that depending on the values the human has supplied so far, additional values may become necessary, so it may be necessary to iterate though several calls to the getPropertyInfo method.

        HSQLDB-Specific Information:

        HSQLDB uses the values submitted in info to set the value for each DriverPropertyInfo object returned.

        Only the connection properties are considered. General database properties are ignored.

        Specified by:
        getPropertyInfo in interface java.sql.Driver
        Parameters:
        url - the URL of the database to which to connect
        info - a proposed list of tag/value pairs that will be sent on connect open
        Returns:
        an array of DriverPropertyInfo objects describing possible properties. This array may be an empty array if no properties are required.

      • getMajorVersion

        public int getMajorVersion()
        Retrieves the driver's major version number. Initially this should be 1.
        Specified by:
        getMajorVersion in interface java.sql.Driver
        Returns:
        this driver's major version number

      • getMinorVersion

        public int getMinorVersion()
        Gets the driver's minor version number. Initially this should be 0.
        Specified by:
        getMinorVersion in interface java.sql.Driver
        Returns:
        this driver's minor version number

      • jdbcCompliant

        public boolean jdbcCompliant()
        Reports whether this driver is a genuine JDBC Compliant driver. A driver may only report true here if it passes the JDBC compliance tests; otherwise it is required to return false.

        JDBC compliance requires full support for the JDBC API and full support for SQL 92 Entry Level. It is expected that JDBC compliant drivers will be available for all the major commercial databases.

        This method is not intended to encourage the development of non-JDBC compliant drivers, but is a recognition of the fact that some vendors are interested in using the JDBC API and framework for lightweight databases that do not support full database functionality, or for special databases such as document information retrieval where a SQL implementation may not be feasible.

        Specified by:
        jdbcCompliant in interface java.sql.Driver
        Returns:
        true if this driver is JDBC Compliant; false otherwise

      • getParentLogger

        public java.util.logging.Logger getParentLogger()
                                         throws java.sql.SQLFeatureNotSupportedException
        Return the parent Logger of all the Loggers used by this driver. This should be the Logger farthest from the root Logger that is still an ancestor of all of the Loggers used by this driver. Configuring this Logger will affect all of the log messages generated by the driver. In the worst case, this may be the root Logger.
        Specified by:
        getParentLogger in interface java.sql.Driver
        Returns:
        the parent Logger for this driver
        Throws:
        java.sql.SQLFeatureNotSupportedException - if the driver does not use java.util.logging.
        Since:
        JDK 1.7, HSQLDB 2.0.1