Connection pooling in JSP

how to maintain database connectivity in each jsp file without explicitly opening connection in each jsp file.

Write one ConnectionManager Class and use that object in every JSP file.

Similar Messages

Connection Pooling and JSP Custom Tag Library - is code (inside) the best way/correc?

Hi, can anyone advise as to whether my tag library code (based
on Apache Jakarta Project) will actually achieve connection
pooling functionality across my entire JSP based application? I
am slightly concerned that my OracleConnectionCacheImpl object
may exist multiple times, hence rendering my conection pooling
attempt useless.
package com.solved.tag.dbtags.connection;
import java.io.IOException;
import java.sql.Connection;
import java.sql.SQLException;
import javax.servlet.jsp.tagext.TagSupport;
import javax.servlet.jsp.JspTagException;
import javax.sql.DataSource;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import oracle.jdbc.pool.OracleConnectionCacheImpl;
* JSP tag connection, used to get a
* java.sql.Connection object.
* JSP Tag Lib Descriptor
* <pre>
* <name>connection</name>
<tagclass>com.solved.tag.dbtags.connection.ConnectionTag</t
agclass>
* <bodycontent>JSP</bodycontent>
<teiclass>com.solved.tag.dbtags.connection.ConnectionTEI</t
eiclass>
* <info>Opens a connection based on a jndiName.</info>
* <attribute>
* <name>id</name>
* <required>true</required>
* <rtexprvalue>false</rtexprvalue>
* </attribute>
* </pre>
* @author Matt Shannon
public class ConnectionTag extends TagSupport {
static private OracleConnectionCacheImpl cache = null;
public int doStartTag() throws JspTagException {
try {
Connection conn = null;
if (cache == null) {
try {
InitialContext ic = new InitialContext();
DataSource ds = (DataSource) ic.lookup
("jdbc/pool/OracleCache");
cache = (OracleConnectionCacheImpl)ds;
catch (NamingException ne) {
throw new JspTagException(ne.toString());
conn = cache.getConnection();
pageContext.setAttribute(getId(),conn);
catch (SQLException e) {
throw new JspTagException(e.toString());
return EVAL_BODY_INCLUDE;
package com.solved.tag.dbtags.connection;
import java.sql.Connection;
import java.sql.SQLException;
import javax.servlet.jsp.tagext.TagSupport;
* JSP tag closeconnection, used to close the
* specified java.sql.Connection.
* JSP Tag Lib Descriptor
* <pre>
* <name>closeConnection</name>
<tagclass>com.solved.tag.dbtags.connection.CloseConnectionTag&
lt;/tagclass>
* <bodycontent>empty</bodycontent>
* <info>Close the specified connection. The "conn"
attribute is the name of a
* connection object in the page context.</info>
* <attribute>
* <name>conn</name>
* <required>true</required>
* <rtexprvalue>false</rtexprvalue>
* </attribute>
* </pre>
* @author Matt Shannon
* @see ConnectionTag
public class CloseConnectionTag extends TagSupport {
private String _connId = null;
* The "conn" attribute is the name of a
* page context object containing a
* java.sql.Connection.
* @param connectionId
* attribute name of the java.sql.Connection to
close.
* @see ConnectionTag
public void setConn(String connectionId) {
_connId = connectionId;
public int doStartTag() {
try {
Connection conn = (Connection)pageContext.getAttribute
(_connId);
conn.close();
} catch (SQLException e) {
// failing to close a connection is not fatal
e.printStackTrace();
return EVAL_BODY_INCLUDE;
public void release() {
_connId = null;
package com.solved.tag.dbtags.connection;
import javax.servlet.jsp.tagext.TagData;
import javax.servlet.jsp.tagext.TagExtraInfo;
import javax.servlet.jsp.tagext.VariableInfo;
* TagExtraInfo for the connection tag. This
* TagExtraInfo specifies that the ConnectionTag
* assigns a java.sql.Connection object to the
* "id" attribute at the end tag.
* @author Matt Shannon
* @see ConnectionTag
public class ConnectionTEI extends TagExtraInfo {
public final VariableInfo[] getVariableInfo(TagData data)
return new VariableInfo[]
new VariableInfo(
data.getAttributeString("id"),
"java.sql.Connection",
true,
VariableInfo.AT_END
data-sources.xml:
<?xml version="1.0"?>
<!DOCTYPE data-sources PUBLIC "Orion data-
sources" "http://xmlns.oracle.com/ias/dtds/data-sources.dtd">
<data-sources>
<data-source
class="oracle.jdbc.pool.OracleConnectionCacheImpl"
name="jdbc/pool/OracleCache"
location="jdbc/pool/OracleCache"
url="jdbc:oracle:thin:@oracle1:1521:pdev"
>
<property name="maxLimit" value="15" />
<property name="cacheScheme" value="2" />
<property name="user" value="console" />
<property name="password" value="console" />
<description>
This DataSource is using an Oracle-native DataSource Class so as
to allow Oracle Specific extensions.
A getConnection() call on this DataSource will return
oracle.jdbc.driver.OracleConnection.
The connection returned is a logical connection.
The caching scheme in place is Fixed Wait. Refer below to
possible values.
Dynamic 1
Fixed Wait 2
Fixed Return Null 3
</description>
</data-source>
</data-sources>
many thanks,
Matt.

Hi. Show me your pool definition.
Joe
Ramamurthy wrote:
I am using the jsp custom tag library from BEA called sqltags.tld which came with Weblogic 5.1. Currently I am using Weblogic6.1 sp2 on Solaris.
I have created a Connection Pool for Sybase database using the driver com.sybase.jdbc.SybDriver.
When I created jsp page to connect to the connection pool using sqltags custom tag library, I am getting the error
"javax.servlet.jsp.JspException: Failed to write body content
at weblogic.taglib.sql.ConnectionTag.doAfterBody(ConnectionTag.java:43)
at jsp_servlet.__hubwcdata._jspService(__sampletest.java:1014)"
After this message, whenever I try to access the same jsp page I am getting the message
"javax.servlet.jsp.JspException: Failed to load JDBC driver: weblogic.jdbc.pool.D
river
at weblogic.taglib.sql.ConnectionTag.doStartTag(ConnectionTag.java:34)
at jsp_servlet.__hubwcdata._jspService(__sampletest.java:205)".
Can you please help me the reason why this problem is happening and how to fix this ?
This problem doexn't happen consistently. This occurs once in a while.
I tried to increase Login delay Seconds parameter in the Connection Pool to 15 sec. It didn't help me much.
Thanks for your help !!!
Ram

How do i use Connection pool in JSP pages

Hey everyone,
I am using a connection pool in my web application. I am using DbConnectionBroker from Javaexchange.com. It has a class that creates a connection pool available for the servlets. I am trying to figure out that how to use connection pool within the JSP pages if I want to connect to the database. In the servlets i am using DBConnectionBroker pool = (DbConnectionBroker) getServletContext().getAttribute("dbPool") to get database connection. How Can i use this in JSP page to get a db connection.
Thanks

If the reference to the connection pool is already stored as an ServletContex attribute, try:
<jsp:useBean id="dbPool" scope="application" class="com.javaexchange.dbConnectionBroker" />
<%
Connection con = dbPool.getConnection();
%>

How to use connection pooling in jsp?

I'm new to world of JSP. I'm developing web application using Oracle 8i and JSP to implement it. I'm using jakarta-tomcat server for this purpose.
I'll frequently access the database. so I want to use the connection pooling.
Can anybody explain the simple procedure to use it
thanx

Hello syyuen,
Please help me, here iam sending u my server.xml , web.xml and servlet
application. I put classes12.jar in tomcat/common/lib. and above servlet
class application under tomcat/webapps/root/web-inf/classes
and this is a simple servlet program for getting connection from the
connection pool of tomcat using tyrex..
my oracle database name is "myuser" and password is "mypass"
either u check my server.xml or tell me where under which tag should i
place <Resource...> tag in server.xml and should i need to modify any
other places..??
server.xml
<Server port="8005" shutdown="SHUTDOWN" debug="0">
 
<Service name="Tomcat-Standalone">
 
<Connector className="org.apache.catalina.connector.http.HttpConnector"
port="8080" minProcessors="5" maxProcessors="75"
enableLookups="true" redirectPort="8443"
acceptCount="10" debug="0" connectionTimeout="60000"/>
 
<Connector className="org.apache.ajp.tomcat4.Ajp13Connector"
port="8009" minProcessors="5" maxProcessors="75"
acceptCount="10" debug="0"/>
 
<Engine name="Standalone" defaultHost="localhost" debug="0">
 
<Logger className="org.apache.catalina.logger.FileLogger"
prefix="catalina_log." suffix=".txt"
timestamp="true"/>
 
 
 
<Realm className="org.apache.catalina.realm.JDBCRealm" debug="99"
 driverName="oracle.jdbc.driver.OracleDriver"
 connectionURL="jdbc:oracle:thin:@oracle:1521:ORCL"
connectionName = "mail"
connectionPassword = "mail"
 userTable="users" userNameCol="user_name" userCredCol="user_pass"
 userRoleTable="user_roles" roleNameCol="role_name" />
 
 
<Host name="localhost" debug="1" appBase="webapps" unpackWARs="true">
 <Valve className="org.apache.catalina.valves.AccessLogValve"
 directory="logs" prefix="localhost_access_log." suffix=".txt"
 pattern="common"/>
<Logger className="org.apache.catalina.logger.FileLogger"
directory="logs" prefix="localhost_log." suffix=".txt"
 timestamp="true"/>
 
 
 
<Context path="/manager" docBase="manager" debug="0" privileged="true"/>

 <Context path="/localhost" docBase="localhost" debug="0" reloadable="false" override="true">
 <Resource name="jdbc/myConnection" auth="SERVLET" type="javax.sql.DataSource"/>
 <ResourceParams name="jdbc/myConnection">
 <parameter><name>user</name><value>myuser</value></parameter>
 <parameter><name>password</name><value>mypass</value></parameter>
 <parameter><name>driverClassName</name><value>oracle.jdbc.driver.OracleDriver</value></parameter>
 <parameter>
 <name>url</name>
 <value>jdbc:oracle:thin:@oracle:1521:ORCL</value>
 </parameter>
 <parameter>
 <name>maxActive</name>
 <value>32</value>
 </parameter>
 <parameter>
 <name>maxIdle</name>
 <value>10</value>
 </parameter>
 </ResourceParams>




</Context>
</Host>
</Engine>
</Service>
 
<Service name="Tomcat-Apache">
<Connector className="org.apache.catalina.connector.warp.WarpConnector"
port="8008" minProcessors="5" maxProcessors="75"
enableLookups="true" appBase="webapps"
acceptCount="10" debug="0"/>
 
<Engine className="org.apache.catalina.connector.warp.WarpEngine"
name="Apache" debug="0">
 
<Logger className="org.apache.catalina.logger.FileLogger"
prefix="apache_log." suffix=".txt"
timestamp="true"/>
 
<Realm className="org.apache.catalina.realm.MemoryRealm" />
</Engine>
</Service>
</Server>
web.xml
<web-app>
<servlet>
<servlet-name>conServlet</servlet-name>
<servlet-class>conServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>conServlet</servlet-name>
<url-pattern> /conServlet </url-pattern>
</servlet-mapping>
<resource-ref>
<description> Resource reference to java.sql.Connection
factory defined in server.xml
</description>
<res-ref-name>jdbc/myConnection</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>
servlet application
DataSource ds = (DataSource) new InitialContext().lookup("java:comp/env/jdbc/myConnection");
conn = ds.getConnection();
out.println("conn : " + conn);

How to use connection pools in jsp

hi
i am new to jsp
i want to connect to database from my jsp
i did it with using java.sql.DriverManager
now how can i modify that with a connection pool

Search the forum. This is answered several times in the past.

How to use connection pool in jsp/servlet ?

I found I can "lookup" it in either java beans/servlets/JSP using JNDI. why?
what is the best practice to use it in a jsp/servlet web app considering JNDI lookuping expensive?
Thanks!
Bo
Edited by: BobXu on Nov 17, 2008 2:27 PM
Edited by: BobXu on Nov 17, 2008 2:32 PM

Huh?
You can lookup a JNDI resource from anywhere in java code you want to. As long as you have a repository set up to search on :-)
Of course whether that resource is available or not is a different matter. If you let the server set up the JNDI resource for you, then you can't run it standalone outside the server without something else setting the same thing up :-)
So its not so much a limitation of beans, but just the environment you run the code in.
Best practice? Don't write sql queries in JSP pages :-)
For the rest you might consider the DAO pattern. Or ignore SQL altogether and let hibernate do the work there for you.
Cheers,
evnafets

How to access database from applet using connection pooling.

Hi,
I am using tomcat 4.1, JRE 1.4.2_10, MySQL 5.0, and IE 6.0. I can access the database using connection pooling from JSP without problems. But, if I try to acess from the applet, I get the following exception (related to JNDI.):
javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file: java.naming.factory.initial
at javax.naming.spi.NamingManager.getInitialContext(Unknown Source)
at javax.naming.InitialContext.getDefaultInitCtx(Unknown Source)
at javax.naming.InitialContext.getURLOrDefaultInitCtx(Unknown Source)
at javax.naming.InitialContext.lookup(Unknown Source)
I know what this acception means, but I don't know how to fix it. I set up connection pooling in my Tomcat 4.1 that talks to MySQL 5.0. As I said, when I access from jsp, JNDI works. But, applet complains. Please help. In my applet, the following code accesses the database:
ArrayList toolTipData =
      access.getToolTipData (projectName,interfac);This is the snipet of my Access class:
public ArrayList getToolTipData (String projectName, String interfac) {
    System.out.println("In getToolTipData");
    ArrayList toolTipData = new ArrayList();
   try{
    Context ctx = new InitialContext();
    if(ctx == null )
        throw new Exception("No Context");
    DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/interfacesDB");
    if (ds != null) {
      Connection conn = ds.getConnection();
      if(conn != null) {
          Statement s = conn.createStatement();
          //For some reason paramtized queries don't work, so I am forced
          //to this in slighly less eficient way.
          ResultSet rst = s.executeQuery("select * from interfaces");
          while (rst.next()) {
             if (rst.getString("Project_Name").equals(projectName) &&
                 rst.getString("Interface").equals(interfac)) {
               System.out.println("getToolTipData: ITG #" + rst.getString("ITG"));
               toolTipData.add("ITG #: " + rst.getString("ITG"));
               toolTipData.add("SPNE Prime Name: " +
                               rst.getString("SPNE_Prime_Name"));
               toolTipData.add("PD Prime Name: " +
                               rst.getString("PD_Prime_Name"));
               toolTipData.add("IT Prime Name: " +
                               rst.getString("IT_Prime_Name"));
               toolTipData.add("MLC Priority: " +
                               rst.getString("MLC_Priority"));
               toolTipData.add("Gary's Prime: " + rst.getString("Garys_Prime"));
               toolTipData.add("QA Prime: " + rst.getString("QA_Prime"));
               toolTipData.add("Brief Description: " +
                               rst.getString("Brief_Description"));
               toolTipData.add("Project_Status: " +
                               rst.getString("Project_Status"));
          conn.close();
}catch(Exception e) {
    e.printStackTrace();
return toolTipData;
....

The jsp runs on the server, whereas the applet runs on the client so
you must package with your applet any jndi implementation specific classes
and
Properties props = new Properties();
props.setProperty("java.naming.factory.initial", "org.jnp.interfaces.NamingContextFactory" );
props.setProperty("java.naming.provider.url", "url:1099");
Context ctx = new InitialContext(props);
Object ref = ctx.lookup("...");

Connection pooling in a JSP

I hava an application that uses both a servlet and a JSP and I need to use connection pooling. I have a connectionPool class that works fine in the servlet. I create the pool in my init() method and access it when needed in doGet(). I would like to do the same thing in my JSP, but since the server creates the servlet code, how can I create the connectionPool only once rather than every time the JSP is invoked? In other words, what can I do to simulate a servlet's init() method in a JSP?

If you read the JavaServer Pages specification, you will realize that there is provision for such things.
The following is an extract from the JavaServer Pages specification 1.1...
The contract also describes how a JSP author can indicate that some actions must be taken
when the init() and destroy() methods of the page implementation occur. In JSP 1.1 this is
done by defining methods with name jspInit() and jspDestroy() in a declaration scripting
element in the JSP page. Before the first time a request is delivered to a JSP page a jspInit()
method, if present, will be called to prepare the page. Similarly, a JSP container can reclaim
the resources used by a JSP page at any time that a request is not being serviced by the JSP
page by invoking first its jspDestroy() method, if present.
So, you should dfine a method with the signature public void jspInit() in your JSP and do the one time initialization therein. Also, you do the associated cleanup in a method with the signature public void jspDestroy()

How do I expand my simple JSP page to implement Connection Pooling?

Hi everyone,
I have a small SQL database which contains information about Students and a StudenBean which contains their attributes and appropriate get/set methods (which I haven't needed to use yet).
I want to write a simple JSP page which displays all the students details in one big table. I can do this using the basic prototyping method of adding the dataSource and driver details to the deployment descriptor (web.xml - I'm using the latest version of Tomcat by the way) and then accessing the database using JSP standard SQL actions.
Here's a snipet of what I've done (just an example, the final code works):
<sql:query var="temp"
sql="SELECT * FROM Employee ORDER BY UserName"
/>
<c:forEach items="${temp.rows}" var="row">
<td><c:out value ="${row.UserName}"/></td>
<td><c:out value ="${row.FirstName}"/></td>
<td><c:out value ="${row.LastName}"/></td>
Now I want to upgrade! I want to access the dataSource using Connection Pooling and it's causing me a lot of trouble. I already have the required working classes/data such as ConnectionPool.java, ResourceManagerListener.java, the MySQL driver etc.
However, I don't know what the best way to setup the connection for my purposes would be and where I should do it.
Do I need to write a servlet or tag handler/custom action to establish the connection and access my bean through it? I would like to keep a similar sort of business logic as I already have developed i.e. be able to use actions in my JSP page to cycle through the database and print out each detail from the row.
Rather confused and muddled. Thanks for any input!

Good idea.
Set up a JNDI data source for your app, according to these docs:
http://jakarta.apache.org/tomcat/tomcat-4.1-doc/jndi-datasource-examples-howto.html
You'll have to put the right information into your web.xml and a context.xml. Once you've done that, your JSTL JSPs will simply use the connection resource automagically.
MOD

JSP Connection Pooling Please Help

Hi,
I have a bean that I want to use for connection pooling with my JSP's. Its constructor creates the pool of connections and I have a getConnection method which retrieves available ones.
My problem is that I create a new instance of the bean on each jsp page I am using. So that means when I go to my next web page and want to grab a connection I recreate an instance of the bean and therefore am creating another pool all over again.
How do I get around this. When I first create an instance of the bean from a .jsp should I make the scope of that bean equal session. That way will I be able to use the same instance throughout the whole site.
Please help
Thanks
Natasha

Hi,
<jsp:useBean> first tries to locate in the scope specified for the bean.If it doesn't find any, then it will instantiates the bean.
Set the beans scope as "application" which means the same bean is available throughout the application.
Hope this helps.
With Regards
Gayam_Slash

Ias support for EJB, JSP/servlets,JDBC, connection pooling, XML, SOAP, load balancing etc

Please let me know where I can find more information regarding iPlanet usage/deployment/configuring/tuning etc for support of technologies - like EJB, JSP/servlets, JDBC, connection pooling, XML, load balancing, JDBC & Transactions
(I have already read the 'Getting Started with the iPlanet Application Server' part five and six - http://developer.iplanet.com/appserver/testdrive/partfive.jsp and partsix.jsp)(I am using the ias testdrive version).

Hi,
It's difficult to explain unless the J2EE architecture is understood. Also, explaining things like load balancing, Transactions, tuning, are bit vague and could blow the disk space of this site.
To get started, the best way is to test the sample applications and the best part is you don't require internet connection to follow each steps. Install iWS and iAS, open browser, type in http://hostname:port/ias-samples/index.html. You can find links to the sample applications bundled. Please follow the steps given on deploying the application. This will enable you to a higher level.
Regards
Ganesh .R
Developer Technical Support
Sun Microsystems
http://www.sun.com/developers/support

Serious connection pool problem on Tomcat

Hi,
We are deploying our JSF creator-made app onto Tomcat 1.5. We set up our JNDI datasource on Tomcat (using the i-net driver ).
Initially the pages load ok but after a short period of time we are getting these errors:
Initialization Failure: javax.faces.FacesException: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot get a connection, pool exhaustedWe believe that somehow the Creator-generated code is NOT freeing up connections in the connection pool.
We think that when the afterRenderResponse() methods in the beans call rowset.close() this is NOT returning the connections to the pool. Can someone, hopefully a Sun Engineer confirm that the rowset.close() code in afterRenderResponse() returns the connection behind the rowset to the connection pool.
Could this be a driver issue? We are using the i-net driver not the DataDirect one, but this should implement the full API.
This is a very serious problem for us.
regards,
john

do you have any example code you could post? I have a Spring/JSC tutorial on this forum. Just search for Spring and you should find it. It you need something more, I'll try to give you some help...time provided.
am i
right in thinking that you use the forms designer to
lay out your pages and just put your own stuff in the
bean constructor?Close...but not everything goes in the constructor.
>
One thing that may have caused a problem is we have
just noticed that in one of our most commonly hit
pages this line:
dataTable1Model.setDataCacheKey("com.sun.datacache.my_
page.my_rowset");
featured the WRONG "my_page" jsp page but the correct
rowset name "my_rowset". The page DID load correctly
and run correctly, though. Could this cause problems
with connection pooling? Anyone?I wouldn't think so, but it depends on how Creator builds the code.

Connection pool not re-establishing connections, throwing exception instead

Hello,
I've just set up a connection pool on the sun java system application server 8 for a MySQL database using the official mysql-connector/j 5.0. Everything is working great, except when the connections timeout (or i kill them all manually from the database server) and then request a page that needs to use the DataSource object, the following exception is thrown:
Exception thrown: com.mysql.jdbc.CommunicationsException -- Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.io.EOFException
STACKTRACE:
java.io.EOFException
 at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1913)
 at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2304)
 at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2803)
 at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1573)
 at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1665)
 at com.mysql.jdbc.Connection.execSQL(Connection.java:3118)
 at com.mysql.jdbc.Connection.execSQL(Connection.java:3047)
 at com.mysql.jdbc.Statement.executeQuery(Statement.java:1166)
 at com.mysql.jdbc.jdbc2.optional.StatementWrapper.executeQuery(StatementWrapper.java:705)
 at beans.MySessionBean.businessMethod(MySessionBean.java:73)
 at org.apache.jsp.index_jsp._jspService(index_jsp.java:70)
 at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:105)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
 at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:336)
 at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
 at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:251)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:860)
 at sun.reflect.GeneratedMethodAccessor98.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:249)
 at java.security.AccessController.doPrivileged(Native Method)
 at javax.security.auth.Subject.doAsPrivileged(Subject.java:517)
 at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:282)
 at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:165)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:257)
 at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:55)
 at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:161)
 at java.security.AccessController.doPrivileged(Native Method)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:263)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:551)
 at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:225)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:173)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:551)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:551)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:132)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:551)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:933)
 at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:185)
 at com.sun.enterprise.web.connector.grizzly.ProcessorTask.process(ProcessorTask.java:653)
 at com.sun.enterprise.web.connector.grizzly.ProcessorTask.process(ProcessorTask.java:534)
 at com.sun.enterprise.web.connector.grizzly.ProcessorTask.doTask(ProcessorTask.java:403)
 at com.sun.enterprise.web.connector.grizzly.WorkerThread.run(WorkerThread.java:55)
** END NESTED EXCEPTION **
Last packet sent to the server was 16 ms ago.What could be wrong?
Thank you.

The code is here:
 public String businessMethod() {
 //TODO implement businessMethod
 try
 InitialContext ic = new InitialContext();
 Object obj = ic.lookup("jdbc/MyDS");
 System.out.println("Object is: " + obj + " | Class is: " + obj.getClass().getName());
 DataSource ds = (DataSource)obj;
 Connection conn = ds.getConnection();
 Statement stmt = conn.createStatement();
 ResultSet rs = stmt.executeQuery("SELECT a,b FROM test");
 String ret = "";
 while(rs.next())
 ret += rs.getString(1) + " - " + rs.getString(2) + " ";
 conn.close();
 return ret;
 catch(Exception e)
 return "Exception thrown: " + e.getClass().getName() + " -- " + e.getMessage();
 }On the server, it is set up as XADataSource. I don't really have a big need for distributed transactions, but does it hurt badly to use it anyways? Could it be causing this problem?

Cursor bound to out parameter with Connection Pool

Is it possible to retrieve a cursor bound to an out parameter when using the thin
driver to establish the connection pool to the database? I am currently using
the JDriver to connect create the pool and the pool driver to connect from the
app to the connection pool. We'd like to avoid using the Oracle client if possible.
Currently I register the out parameter as java.sql.Types.OTHER, then call getResultSet(1)
on the weblogic.jdbc.pool.CallableStatement object. But it breaks when I change
the connection pool to use the thin driver. The error is at the bottom of this
post.
I think I could possibly get the current pool driver to work if can find some
documentation on these two methods:
void registerOutParameter(int i, int j, int k, int l)
void registerOutParameter(int i, int sqlType, java.lang.String typeName)
I have no idea what to put in for the ints in the first method or for sqlType
or typeName. Can anyone point me to where I can find this documentation?
E-docs mentions this class: weblogic.jdbc.vendor.oracle.OracleCallableStatement.
(http://edocs.bea.com/wls/docs61/jdbc/thirdparty.html#1023867). Should I consider
this? If so where is it?
Thanks a lot,
Matt Savino
<<< error when using thin driver >>>
preparing callable stmt
callable stmt prepared, java.sql.Types.OTHER = 1111
java.sql.SQLException: Invalid column type
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:168)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:210)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:273)
at oracle.jdbc.driver.OracleStatement.get_internal_type(OracleStatement.java:4560)
at oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallableStatement.java:225)
at oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallableStatement.java:350)
at weblogic.jdbc.pool.Statement.registerOutParameter(Statement.java:617)
at jsp_servlet._reportmanager.__thin_outputresultset._jspService(__thin_outputresultset.java:145)
at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:263)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:200)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:2390)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1959)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)

Thanks Joe, your answer pointed me in the right direction. Just in case anyone
wants to know, the solution took two changes:
CHANGE
cStat.registerOutParameter(1, java.sql.Types.OTHER);
TO
cStat.registerOutParameter(1, oracle.jdbc.driver.OracleTypes.CURSOR);
(cStat is an instance of weblogic.jdbc.pool.CallableStatement)
AND
rs = cStat.getResultSet(1);
TO
rs = cStat.getCursor(1);
Thanks again,
Matt
Joseph Weinstein <[email protected]> wrote:
Hi Matt.
Look at the Oracle thin driver documentation to determine what type you
should define in the registerOutParameter call. We use 'OTHER', but
their driver may use something else for CURSOR output parameters.
joe
Matt Savino wrote:
Is it possible to retrieve a cursor bound to an out parameter whenusing the thin
driver to establish the connection pool to the database? I am currentlyusing
the JDriver to connect create the pool and the pool driver to connectfrom the
app to the connection pool. We'd like to avoid using the Oracle clientif possible.
Currently I register the out parameter as java.sql.Types.OTHER, thencall getResultSet(1)
on the weblogic.jdbc.pool.CallableStatement object. But it breaks whenI change
the connection pool to use the thin driver. The error is at the bottomof this
post.
I think I could possibly get the current pool driver to work if canfind some
documentation on these two methods:
void registerOutParameter(int i, int j, int k, int l)
void registerOutParameter(int i, int sqlType, java.lang.String typeName)
I have no idea what to put in for the ints in the first method or forsqlType
or typeName. Can anyone point me to where I can find this documentation?
E-docs mentions this class: weblogic.jdbc.vendor.oracle.OracleCallableStatement.
(http://edocs.bea.com/wls/docs61/jdbc/thirdparty.html#1023867). Should
I consider
this? If so where is it?
Thanks a lot,
Matt Savino
<<< error when using thin driver >>>
preparing callable stmt
callable stmt prepared, java.sql.Types.OTHER = 1111
java.sql.SQLException: Invalid column type
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:168)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:210)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:273)
at oracle.jdbc.driver.OracleStatement.get_internal_type(OracleStatement.java:4560)
at oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallableStatement.java:225)
at oracle.jdbc.driver.OracleCallableStatement.registerOutParameter(OracleCallableStatement.java:350)
at weblogic.jdbc.pool.Statement.registerOutParameter(Statement.java:617)
at jsp_servlet._reportmanager.__thin_outputresultset._jspService(__thin_outputresultset.java:145)
at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:263)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:200)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:2390)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1959)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
PS: Folks: BEA WebLogic is expanding rapidly, with both entry and advanced
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We have jobs at Nashua NH, Liberty Corner NJ, San Francisco and San Jose
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How to use JDBC Connection Pools in a standalone application?

Hi, there,
I have a question about how to use JDBC Connection Pools in an application. I know well about connection pool itself, but I am not quite sure how to keep the pool management object alive all the time to avoid being destroyed by garbage collection.
for example, at the website: http://www.developer.com/java/other/article.php/626291, there is a simple connection pool implementation. there are three classes:JDBCConnection, the application's gateway to the database; JDBCConnectionImpl, the real class/object to provide connection; and JDBCPool, the management class to manage connection pool composed by JDBCConnectionImpl. JDBCPool is designed by Singleton pattern to make sure only one instance. supposing there is only one client to use connection for many times, I guess it's ok because this client first needs instantiate JDBCPool and JDBCConnectionImpl and then will hold the reference to JDBCPool all the time. but how about many clients want to use this JDBCPool? supposing client1 finishes using JDBCPool and quits, then JDBCPool will be destroyed by garbage collection since there is no reference to it, also all the connections of JDBCConnectionImpl in this pool will be destroyed too. that means the next client needs recreate pool and connections! so my question is that if there is a way to keep pool management instance alive all the time to provide connection to any client at any time. I guess maybe I can set the pool management class as daemon thread to solve this problem, but I am not quite sure. besides, there is some other problems about daemon thread, for example, how to make sure there is only one daemon instance? how to quit it gracefully? because once the whole application quits, the daemon thread also quits by force. in that case, all the connections in the pool won't get chance to close.
I know there is another solution by JNDI if we develop servlet application. Tomcat provides an easy way to setup JNDI database pooling source that is available to JSP and Servlet. but how about a standalone application? I mean there is no JNDI service provider. it seems a good solution to combine Commons DBCP with JNID or Apache's Naming (http://jakarta.apache.org/commons/dbcp/index.html). but still, I don't know how to keep pool management instance alive all the time. once we create a JNDI enviroment or naming, if it will save in the memory automatically all the time? or we must implement it as a daemon thread?
any hint will be great apprieciated!
Sam

To my knoledge the pool management instance stays alive as long as the pool is alive. What you have to figure out is how to keep a reference to it if you need to later access it.

Connection pooling in JSP

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