DataSource: Difference between revisions

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DataSource ds;
DataSource ds;


ds.
Connection c;
</syntaxhighlight>


=TODO=
try {


* https://home.feodorov.com:9443/wiki/Wiki.jsp?page=JBossDataSource
  c = ds.getConnection();
 
  ...


=Organizatorium=
}
finally {


  if (c != null) {


      c.close();
  }
}
</syntaxhighlight>


According to JDBC Javadoc, a DataSource is a ''factory for connections'' to the physical data source that this DataSource object represents.
=JDBC API Usage=
 
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();
{{Internal|JDBC API Usage|JDBC API Usage}}
}}}

Latest revision as of 14:47, 26 September 2017

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.

DataSource Instance 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(name="java:/DefaultDS")
DataSource ds;

@Resource(name="java:/DefaultDS")
public void setDataSource(DataSource ds) {
   this.ds = 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");

Connection Life Cycle

import java.sql.Connection;

...

DataSource ds;

Connection c;

try {

  c = ds.getConnection();
  
  ...

}
finally {

  if (c != null) {

      c.close();
  }
}

JDBC API Usage

JDBC API Usage