I have a Java project and I've been trying to create a JNDI connection for my Ingres database but have been unsuccessful. I'm not sure if there is something specific to ingres that needs to be included but after quite a bit of research I haven't been able to get things to work.
In my project I have my datasource info in the web.xml file and the context.xml
context.xml has the following info
<Context>
<Resource name="jdbc/myDB" auth="Container" type="javax.sql.Datasource"
username="myUser" password="password" driverClassName="com.ingres.jdbc.IngresDriver"
url="databaseURL" maxActive="8" maxIdle="4" maxWait="100" />
</Context>
My web.xml has the following info
<web-app>
<resource-ref>
<description>Project Descrip</description>
<res-ref-name>jdbc/myDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>
In my java code I'm trying to get my connection using the following four lines
Context initContext = new InitialContext();
Context envContext = (Context) initContent.lookup("java:comp/env");
Datasource ds = (DataSource) envContext.lookup("jdbc/myDB");
return ds.getConnection();
After the third line is executed I get an exception that says: NamingException - Cannot create resource instance
I have found dozens of posts with this same exception and have tried the suggested solutions with no luck. I'm using a Tomcat 7 server and have made sure to include the necessary ingres jar (iijdbc.jar) to my WEB-INF/lib folder and to my tomcat lib folder.
Any help or suggestions would be greatly appreciated
I don't know much about Ingres, but if attempting to make a datasource is similar to JBOSS and DB2 or MySQL. I noticed that in your WEB.XML you define your resource-ref, but you don't mention the anything about the servlet parameters.
<servlet>
<description>Servlet Description</description>
<display-name>MyServlet</display-name>
<servlet-name>MyServlet</servlet-name>
<servlet-class>servlet.MyServlet</servlet-class>
<init-param>
<param-name>MyDB</param-name>
<param-value>java:comp/env/jdbc/MyDB</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
Then you would need to code in your sevlet:
InitialContext initialContext = new InitialContext();
DataSource dataSource = (DataSource)initialContext.lookup(this.getInitParameter("MyDB"));
Hope this helps.
Can you try adding global="jdbc/myDB"
attribute as in your Resource
tag as follows:
<Context>
<Resource name="jdbc/myDB" auth="Container" type="javax.sql.Datasource"
username="myUser" password="password" driverClassName="com.ingres.jdbc.IngresDriver"
url="databaseURL" maxActive="8" maxIdle="4" maxWait="100" global="jdbc/myDB"/>
</Context>
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