DataSource

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External

Internal

Overview

This page refers to a JSE javax.sql.DataSource. The DataSource is part of JDBC and it is the main interface exposed by the javax.sql package. DataSource is part of JSE since 1.4. JDBC specifies that a database Connection can be obtained from a DriverManager or a DataSource. The DataSource is the preferred way of getting the Connection. JEE also mentions DataSource, defining it as a resource manager connection factory for java.sql.Connection objects.

Initialization

A DataSource instance can be injected by annotating a field or a method of a JEE component with the JEE @javax.annotation.Resource annotation:

import javax.sql.DataSource;

...

@Resource
DataSource ds;

@Resource
public void setDataSource(DataSource ds) {
   ...
}

For more details on attributes supported by the @Resource annotation see:

@javax.annotation.Resource

A DataSource can also be looked up in JNDI:

import javax.sql.DataSource;

...

DataSource ds = (DataSource)ic.lookup("java:/DefaultDS");

TODO

Organizatorium

According to JDBC Javadoc, a DataSource is a factory for connections to the physical data source that this DataSource object represents.

An object that implements the DataSource interface will typically be registered with a naming service based on the JavaTM Naming and Directory (JNDI) API.

Example: {{{

      DataSource ds = (DataSource)ic.lookup("java:/DefaultDS");
      Connection conn = ds.getConnection();
      ....
      conn.close();

}}}