This is my jboss/deploy/postgres-ds.xml file. The connection url, username and password is given here. How do I obtain a connection to this database in my servlet.
<local-tx-datasource>
<jndi-name>PostgresDS</jndi-name>
<connection-url>jdbc:postgresql://localhost:5432/postgres</connection-url>
<driver-class>org.postgresql.Driver</driver-class>
<user-name>postgres</user-name>
<password>qwerty</password>
<!-- sql to call when connection is created
<new-connection-sql>some arbitrary sql</new-connection-sql>
-->
<!-- sql to call on an existing pooled connection when it is obtained from pool
<check-valid-connection-sql>some arbitrary sql</check-valid-connection-sql>
-->
<!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml (optional) -->
</local-tx-datasource>
Should I obtain the connection like this in every servlet :
Connection conn =null; // Create connection object
String database = "postgres"; // Name of database
String user = "postgres"; //
String password = "qwerty";
String url = "jdbc:postgresql://localhost:5432/" + database;
ResultSet rs = null;
ResultSetMetaData rsm = null;
try{
Class.forName("org.postgresql.Driver").newInstance();
//.newInstance()
} catch(Exception e)
{
System.err.println(e);
}
try{
conn = DriverManager.getConnection(url, user, password);
}catch(SQLException se)
{
System.err.println(se);
}
If this has to be done everytime, then why give the url, username and password in the postgres-ds.xml file?
Best Answer
you can use DataSource to get Connection like