org.apache.derby.jdbc
Class ClientDataSource

java.lang.Object
  org.apache.derby.jdbc.ClientBaseDataSource
      org.apache.derby.jdbc.ClientDataSource

All Implemented Interfaces:

java.io.Serializable, javax.naming.Referenceable, javax.sql.DataSource

Direct Known Subclasses:

ClientConnectionPoolDataSource, ClientXADataSource

public class ClientDataSource
extends ClientBaseDataSource
implements javax.sql.DataSource

ClientDataSource is a simple data source implementation that can be used for establishing connections in a non-pooling, non-distributed environment. The class ClientConnectionPoolDataSource can be used in a connection pooling environment, and the class ClientXADataSource can be used in a distributed, and pooling environment. Use these DataSources if your application runs under JDBC3.0 or JDBC2.0, that is, on the following Java Virtual Machines:

• JDBC 3.0 - Java 2 - JDK 1.4, J2SE 5.0
• JDBC 2.0 - Java 2 - JDK 1.2,1.3

The example below registers a DNC data source object with a JNDI naming service.

 org.apache.derby.client.ClientDataSource dataSource = new org.apache.derby.client.ClientDataSource ();
 dataSource.setServerName ("my_derby_database_server");
 dataSource.setDatabaseName ("my_derby_database_name");
 javax.naming.Context context = new javax.naming.InitialContext();
 context.bind ("jdbc/my_datasource_name", dataSource);
 

The first line of code in the example creates a data source object. The next two lines initialize the data source's properties. Then a Java object that references the initial JNDI naming context is created by calling the InitialContext() constructor, which is provided by JNDI. System properties (not shown) are used to tell JNDI the service provider to use. The JNDI name space is hierarchical, similar to the directory structure of many file systems. The data source object is bound to a logical JNDI name by calling Context.bind(). In this case the JNDI name identifies a subcontext, "jdbc", of the root naming context and a logical name, "my_datasource_name", within the jdbc subcontext. This is all of the code required to deploy a data source object within JNDI. This example is provided mainly for illustrative purposes. We expect that developers or system administrators will normally use a GUI tool to deploy a data source object.

Once a data source has been registered with JNDI, it can then be used by a JDBC application, as is shown in the following example.

 javax.naming.Context context = new javax.naming.InitialContext ();
 javax.sql.DataSource dataSource = (javax.sql.DataSource) context.lookup ("jdbc/my_datasource_name");
 java.sql.Connection connection = dataSource.getConnection ("user", "password");
 

The first line in the example creates a Java object that references the initial JNDI naming context. Next, the initial naming context is used to do a lookup operation using the logical name of the data source. The Context.lookup() method returns a reference to a Java Object, which is narrowed to a javax.sql.DataSource object. In the last line, the DataSource.getConnection() method is called to produce a database connection.

This simple data source subclass of ClientBaseDataSource maintains it's own private password property.

The specified password, along with the user, is validated by DERBY. This property can be overwritten by specifing the password parameter on the DataSource.getConnection() method call.

This password property is not declared transient, and therefore may be serialized to a file in clear-text, or stored to a JNDI server in clear-text when the data source is saved. Care must taken by the user to prevent security breaches.

See Also:

Serialized Form

Field Summary

static java.lang.String

className__

Fields inherited from class org.apache.derby.jdbc.ClientBaseDataSource

CLEAR_TEXT_PASSWORD_SECURITY, connectionAttributes, ENCRYPTED_PASSWORD_SECURITY, ENCRYPTED_USER_AND_PASSWORD_SECURITY, propertyDefault_portNumber, propertyDefault_retrieveMessageText, propertyDefault_securityMechanism, propertyDefault_serverName, propertyDefault_traceFileAppend, propertyDefault_traceLevel, propertyDefault_user, securityMechanism, SSL_BASIC, SSL_OFF, SSL_PEER_AUTHENTICATION, STRONG_PASSWORD_SUBSTITUTE_SECURITY, TRACE_ALL, TRACE_CONNECTION_CALLS, TRACE_CONNECTS, TRACE_DIAGNOSTICS, TRACE_DRIVER_CONFIGURATION, TRACE_NONE, TRACE_PARAMETER_META_DATA, TRACE_PROTOCOL_FLOWS, TRACE_RESULT_SET_CALLS, TRACE_RESULT_SET_META_DATA, TRACE_STATEMENT_CALLS, TRACE_XA_CALLS, traceLevel, USER_ONLY_SECURITY

Constructor Summary

ClientDataSource()
Creates a simple DERBY data source with default property values for a non-pooling, non-distributed environment.

Method Summary

java.sql.Connection	getConnection() Attempt to establish a database connection in a non-pooling, non-distributed environment.
java.sql.Connection	getConnection(java.lang.String user, java.lang.String password) Attempt to establish a database connection in a non-pooling, non-distributed environment.

Methods inherited from class org.apache.derby.jdbc.ClientBaseDataSource

computeDncLogWriter, getClientSSLMode, getConnectionAttributes, getCreateDatabase, getDatabaseName, getDataSourceName, getDescription, getLoginTimeout, getLogWriter, getPassword, getPassword, getPortNumber, getReference, getRetrieveMessageText, getRetrieveMessageText, getSecurityMechanism, getSecurityMechanism, getSecurityMechanism, getServerName, getShutdownDatabase, getSsl, getSSLModeFromString, getTraceDirectory, getTraceDirectory, getTraceFile, getTraceFile, getTraceFileAppend, getTraceFileAppend, getTraceLevel, getTraceLevel, getUpgradedSecurityMechanism, getUser, getUser, handleConnectionException, maxStatementsToPool, setConnectionAttributes, setCreateDatabase, setDatabaseName, setDataSourceName, setDescription, setLoginTimeout, setLogWriter, setPassword, setPortNumber, setRetrieveMessageText, setSecurityMechanism, setServerName, setShutdownDatabase, setSsl, setTraceDirectory, setTraceFile, setTraceFileAppend, setTraceLevel, setUser

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.sql.DataSource

getLoginTimeout, getLogWriter, setLoginTimeout, setLogWriter

Field Detail

className__

public static final java.lang.String className__

See Also:

Constant Field Values

Constructor Detail

ClientDataSource

public ClientDataSource()

Creates a simple DERBY data source with default property values for a non-pooling, non-distributed environment. No particular DatabaseName or other properties are associated with the data source.

Every Java Bean should provide a constructor with no arguments since many beanboxes attempt to instantiate a bean by invoking its no-argument constructor.

Method Detail

getConnection

public java.sql.Connection getConnection()
                                  throws java.sql.SQLException

Attempt to establish a database connection in a non-pooling, non-distributed environment.

Specified by:

getConnection in interface javax.sql.DataSource

Returns:

a Connection to the database

Throws:

java.sql.SQLException - if a database-access error occurs.

getConnection

public java.sql.Connection getConnection(java.lang.String user,
                                         java.lang.String password)
                                  throws java.sql.SQLException

Attempt to establish a database connection in a non-pooling, non-distributed environment.

Specified by:

getConnection in interface javax.sql.DataSource

Parameters:

user - the database user on whose behalf the Connection is being made

password - the user's password

Returns:

a Connection to the database

Throws:

java.sql.SQLException - if a database-access error occurs.