org.javasimon.jdbc
Class Driver

java.lang.Object
  org.javasimon.jdbc.Driver

All Implemented Interfaces:

Driver

public final class Driver
extends Object
implements Driver

Simon JDBC Proxy Driver.

An application should not use this class directly. The application (if standalone) should use DriverManager only. For example:

 Connection conn = DriverManager.getConnection("jdbc:simon:oracle:thin:...", "scott", "tiger");

Simon driver has following format of JDBC connection string:

jdbc:simon:<real driver conn string>;<param1>=<value1>;...

Simon driver recognizes two parameters:

• SIMON_REAL_DRV - if you don't want or can't register real driver for any reason, you can use this parameter and Simon proxy driver will do the registration for you. You don't need to specify real driver parameter for some well known databases. Simon proxy driver recognize database by first key word after JDBC and register.
• SIMON_PREFIX - setting this parameter you can choose different prefix for all monitors for one instance of driver. For example, setting SIMON_PREFIX=com.foo will ensure that all proxy related Simons are located under the subtree specified by the prefix, e.g. com.foo.conn, com.foo.stmt, com.foo.select, etc. If no prefix is set, default org.javasimon.jdbc prefix is used.
• SIMON_LOGFILE - setting this parameter you can enable logging events (JDBC activity) to specified file, for example ...;simon_logfile=c:\jdbc.log or ...;simon_logfile=/tmp/jdbc.log.
• SIMON_LOGGER - setting this you can enable logging events (JDBC activity) to specified JDK14 logger (@{link java.util.logging.Logger}), for example ...;simon_logger=my.package.logger.
• SIMON_CONSOLE - setting this you can enable logging events (JDBC activity) to console, which is (System.err) using standard ConsoleHandler, for example ...;simon_console=y or ...;simon_console=true.
• SIMON_FORMAT - by this parameter you can set format of log. There are two build-in formats: human and csv. Custom format is also possible by specifing clasname. Custom formatter must by derived from SimonFormatter. For example ...;simon_format=csv or ...;simon_format=my.package.MyFormmater

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By default, there is no need to load any driver explicitly, because drivers are loaded automatically (since JDK 1.5) if they are in class path and jar have appropriate meta information (see DriverManager).

If this is not a case for any reason, you need to register Simon proxy driver at least. For real driver Simon proxy driver contains following procedure for find and register it:

1. Simon proxy driver tries if there is registered driver for driver key word.
2. If not, driver tries if there is real driver parameter in info properties and then registers it.
3. If not, driver tries to find driver by key word within internal list of well known drivers and then registers it. For now, list contains default drivers for Oracle, PostgreSQL, Enterprise DB, H2, MySQL.
4. If not, driver tries to find real driver param within connection string and then registers it.
5. If not, getting new connection fails.

The safest way to get Simon proxy driver work is to load the drivers, the real one (i.e. oracle) and a Simon proxy driver explicitly. This can be done using Class.forName. To load the driver and open a database connection, use following code:

 Class.forName("oracle.jdbc.driver.OracleDriver");  // loads real driver
 Class.forName("org.javasimon.jdbc.Driver");  // loads Simon proxy driver
 Connection conn = DriverManager.getConnection(
      "jdbc:simon:oracle:thin:...", "scott", "tiger");

Since:

1.0

Version:

$Revision: 304 $ $Date: 2011-04-08 10:39:02 +0200 (Fri, 08 Apr 2011) $

Author:

Radovan Sninsky

See Also:

DriverManager.getConnection(String)

Nested Class Summary

(package private) static class

Driver.Url Class Url represents Simon JDBC url.

Field Summary

private static String	CONSOLE Name for the driver property enabling JDBC logging to console (System.err) using ConsoleHandler.
static String	DEFAULT_PREFIX Default hierarchy prefix for Simon JDBC driver.
private Properties	drivers
private static String	FORMAT Name for the driver property setting format for logs.
private static String	LOGFILE Name for the driver property enabling JDBC logging to specified file.
private static String	LOGGER Name for the driver property enabling JDBC logging to specified JDK14 logger (@{link java.util.logging.Logger}).
static String	PREFIX Name for the driver property holding the hierarchy prefix given to JDBC Simons.
static String	REAL_DRIVER Name for the property holding the real driver class value.

Constructor Summary

Driver()
Class constructor.

Method Summary

boolean	acceptsURL(String url)
Connection	connect(String simonUrl, Properties info) Opens new Simon proxy driver connection associated with real connection to specified database.
int	getMajorVersion()
int	getMinorVersion()
DriverPropertyInfo[]	getPropertyInfo(String s, Properties properties)
private Driver	getRealDriver(Driver.Url url, Properties info) Tries to determine driver class, instantiate it and register if already not registered.
boolean	jdbcCompliant()
private Driver	registerDriver(String name) Registers real driver through DriverManager.
private void	registerLoggingCallback(Driver.Url url) Registers JDBC logging callback to Simon manager.

Methods inherited from class java.lang.Object

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

Field Detail

REAL_DRIVER

public static final String REAL_DRIVER

Name for the property holding the real driver class value.

See Also:

Constant Field Values

DEFAULT_PREFIX

public static final String DEFAULT_PREFIX

Default hierarchy prefix for Simon JDBC driver. All Simons created by Simon JDBC driver without explicitly specified prefix are started with default prefix.

See Also:

Constant Field Values

PREFIX

public static final String PREFIX

Name for the driver property holding the hierarchy prefix given to JDBC Simons.

See Also:

Constant Field Values

LOGFILE

private static final String LOGFILE

Name for the driver property enabling JDBC logging to specified file.

See Also:

Constant Field Values

LOGGER

private static final String LOGGER

Name for the driver property enabling JDBC logging to specified JDK14 logger (@{link java.util.logging.Logger}).

See Also:

Constant Field Values

CONSOLE

private static final String CONSOLE

Name for the driver property enabling JDBC logging to console (System.err) using ConsoleHandler.

See Also:

Constant Field Values

FORMAT

private static final String FORMAT

Name for the driver property setting format for logs. There are two build-in formats: human and csv. Custom format is also possible by specifing clasname, must by derived from SimonFormatter.

See Also:

Constant Field Values

drivers

private final Properties drivers

Constructor Detail

Driver

public Driver()

Class constructor. It loads well known driver list from resource file drivers.properties.

Method Detail

connect

public Connection connect(String simonUrl,
                          Properties info)
                   throws SQLException

Opens new Simon proxy driver connection associated with real connection to specified database.

Specified by:

connect in interface Driver

Parameters:

simonUrl - JDBC connection string (i.e. jdbc:simon:h2:file:test)

info - properties for connection

Returns:

open connection to database or null if provided url is not accepted by this driver

Throws:

SQLException - if there is no real driver registered/recognized or opening real connection fails

See Also:

Driver

registerLoggingCallback

private void registerLoggingCallback(Driver.Url url)

Registers JDBC logging callback to Simon manager.

Parameters:

url - instance of Driver.Url

See Also:

SimonManager.callback(), Callback.addCallback(org.javasimon.Callback)

getRealDriver

private Driver getRealDriver(Driver.Url url,
                             Properties info)
                      throws SQLException

Tries to determine driver class, instantiate it and register if already not registered. For more detail look at Driver class javadoc.

Parameters:

url - instance of url object that represents url

info - parameters from connect(String, java.util.Properties) method

Returns:

instance of real driver

Throws:

SQLException - if real driver can't be determined or is not registerd

registerDriver

private Driver registerDriver(String name)
                       throws SQLException

Registers real driver through DriverManager.

Parameters:

name - real driver class name

Returns:

instance of registered real driver

Throws:

SQLException - if registration fails

acceptsURL

public boolean acceptsURL(String url)
                   throws SQLException

Specified by:

acceptsURL in interface Driver

Throws:

SQLException

getPropertyInfo

public DriverPropertyInfo[] getPropertyInfo(String s,
                                            Properties properties)
                                     throws SQLException

Specified by:

getPropertyInfo in interface Driver

Throws:

SQLException

getMajorVersion

public int getMajorVersion()

Specified by:

getMajorVersion in interface Driver

getMinorVersion

public int getMinorVersion()

Specified by:

getMinorVersion in interface Driver

jdbcCompliant

public boolean jdbcCompliant()

Specified by:

jdbcCompliant in interface Driver