java.lang.NoSuchMethodError: com/ibm/ejs/ras/TraceComponent.isAnyTracingEnabled()Z

Include the com.ibm.ws.webservices.thinclient_6.1.0.jar file is in the classpath.
Remove other jars if present (such as ras.jar, com.ibm.ws.runtime_6.1.0.jar) which contain TraceComponent class

java.lang.NoSuchFieldError: com/ibm/mq/MQC.MQCT_NONE

com.ibm.mq.jar is required in the classpath of the java class.
This jar is supplied with WAS

Unable to use CSS style on the page

I was going nuts why I am unable to view the style on the pages using Struts 2 with AJAX.

I have to investigate but once I removed this line from my JSP it ran fine :-)

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

Show Hide using display.style in javascript problem in Firefox

An already javascript function was used to show/hide an array of elments in an HTML page.
It worked perfectly in IE but in Firefox it gave a problem when we used to show/hide multiple times on an element. A new row/column was added in every iteration of show hide.

On investigation, a single line code change made in work fine in both IE and firefox

Old Code

function showHideElement(elementId, showHideFlag) {
var elementObj = document.getElementById(elementId);
if(showHideFlag == 1) {
elementObj.style.display = 'block';
} else if(showHideFlag == 0) {
elementObj.style.display = 'none';
}
}

New Code

function showHideElement(elementId, showHideFlag) {
var elementObj = document.getElementById(elementId);
if(showHideFlag == 1) {
elementObj.style.display = '';
} else if(showHideFlag == 0) {
elementObj.style.display = 'none';
}
}

A single line change from elementObj.style.display = 'block' to elementObj.style.display = '' stopped creation of blank rows/columns on every iteration of show hide

http://www.ozzu.com/ftopic41924.html
http://www.velocityreviews.com/forums/t160487-firefox-and-stylequotdisplayblockquot-on-table-row.html

Dynamically creating radio buttons using DOM

This post almost replicates my experience while trying to create dynamic radio buttons using DOM
In the Trenches: Another IE Gotcha - Dynamiclly Created Radio Buttons

Some other links which helped me
http://www.thescripts.com/forum/thread468483.html
http://www.fleegix.org/articles/2006/04/29/dom-fun-with-ie6-and-form-elements

No form found under 'null' in locale 'en_US'. A form must be defined in the Commons Validator configuration when dynamicJavascript=&q

As soon as I put &lt;html:javascript /&gt; tag in the jsp, I get this error.
It indicates that it is unable to find a formset.

Solution: Did not add the form name with the tag
ex:

The path of an ForwardConfig cannot be null

Usually, this is an indication that you have validation turned on, the
validation is failing, and the "input" attribute is not set (i.e. it's
NULL)

Source

I was adding validator and forgot to do 'validation="true"' add the 'input' attribute in action mapping

java.sql.SQLException: ORA-01008: not all variables bound

One of the cause of this error can be found in the following snippet of code:

query = "select * from AAA where condn = ?";
pstmt = con.prepareStatement(query);
pstmt.setString(1, firstValue);
// ResultSet rs = pstmt.executeQuery(query); // Wrong Usage - Do not provide query again
ResultSet rs = pstmt.executeQuery(); // Correct Usage

Another reason is that you have not mapped all '?' with corresponding values

ORA-00911: invalid character

The exception was because I had a semicolon(;) after the preparedstatement query.
Removal of it resolved the problem

Database Explorer in Eclipse 3.1

Hi,

These are two Plugins which can be used for exploring the DB.
Hence it will reduce the dependency on PL/SQL Dev and Toad.
1. SourceForge.net: Eclipse SQLExplorer plugin
2. SourceForge.net: DBEdit Plugin for Eclipse

Installation is simple, just extract them in the plugin directory of Eclipse.
After you restart your Eclipse you can see one more Perspective(SQLExplorer/DBEdit) which will depend on which plugin you have installed.

Hopefully once we move to Eclipse 3.2 we will get all this features from the Data Tools Platform.

The  installation instruction for SQL Exlplorer are present on this link
http://www.onjava.com/pub/a/onjava/2005/05/11/sqlexplorer.html

Cannot create JDBC driver of class '' for connect URL 'null'

If you get this Exception while using Tomcat 5.5.9 or 5.5.*

Caused by: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null' at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:780) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540) at com.vsnl.pcr.dao.DataAccessObject.getConnection(DataAccessObject.java:119) ... 29 more

Possible Solution:
Check the database lookup entry in either context.xml or server.xml
In Tomcat 5.5.9 there are no <ResouceParams> tag and the parameters are passed alongiwth the resource tag.

e.g Resource Entry in Tomcat 5.5.9

<resource name="jdbc/XYZ"
    auth="Container"
    scope="Shareable"
    type="javax.sql.DataSource"
    driverclassname="oracle.jdbc.driver.OracleDriver"
    url="jdbc:oracle:thin:@xxx.xxx.xxx.xxx:1521:XYZ"
    username="xyz"
    password="xyz"
    maxactive="10"
    maxidle="100"
    maxwait="3000">
</resource>

In Tomcat 5.0.28

<resource name="jdbc/XYZ" scope="Shareable" type="javax.sql.DataSource">
<resourceparams name="jdbc/XYZ">
<parameter>
  <name>factory</name>
  <value>
      org.apache.commons.dbcp.BasicDataSourceFactory
  </value>
</parameter>
<!-- DBCP database connection settings  -->
<parameter>
  <name>url</name>
   <value>jdbc:oracle:thin:@xxx.xxx.xxx.xxx:1521:XYZ</value>
</parameter>
<parameter>
  <name>driverClassName</name>
  <value>oracle.jdbc.driver.OracleDriver</value>
</parameter>
<parameter>
  <name>username</name>
  <value>xyz</value>
</parameter>
<parameter>
  <name>password</name>
  <value>xyz</value>
</parameter>
<parameter>
  <name>maxWait</name>
  <value>3000</value>
</parameter>
<parameter>
  <name>maxIdle</name>
  <value>100</value>
</parameter>
<parameter>
  <name>maxActive</name>
  <value>10</value>
</parameter>

</resourceparams>
</resource> 

One Last Point: Dont forget to put your classes12.jar/ojdbc14.jar file in /commons/lib folder.

Two useful links which help me discover this.. :-) (after I had already wasted a lot of time)
1. Java Forums
2. Tomcat Docs

Common Struts Errors

Common Struts Errors
A really good compilation of some Common Struts erors and I find it quite handy :-) most of the times

javax.servlet.ServletException: Define tag cannot set a null value

If you are using struts and get this error, it means you might have used
tag for a value which is null.

The problem would be solved if you use tag to check for the null value.
e.g.

1 <logic:notEmpty name="fooForm" property="fooList">
2 <bean:define id="fooList" name="fooForm" property="fooList" />
3 <html:options collection="fooList" property="id" labelProperty="fooname" />
4 </logic:notEmpty>

The 'fooList' is checked before being defined in the samplecode

EclipseZone - Review of Eclipse Web Tools Platform 1.0

EclipseZone - Review of Eclipse Web Tools Platform 1.0

How to Stop double submit on click of refresh button in Struts

Follow these steps if you are using Struts
1. Add saveToken(request) in the execute() method of the Action when the page needs to displayed first or initialized.
2. Add the following code in the execute() method of Action handling the processing of the page on Submit

if (isTokenValid(request)) {
////// Do the processing for the request and add messages if required

resetToken(request); /// Reset the token so that on resubmit it does not come in this block
return mapping.findForward("success");
} else {
///// The page is submitted again so take app. action if required
return mapping.findForward("failure");
}

One-Time Pad Generator

One-Time Pad Generator

I found this site useful for generating a random key.
Its a web based random key generator.

java.sql.SQLException: ORA-01006: bind variable does not exist

It could be because you have left the String variable in the query as '?' and then setting it by setString(, ) and this leads ot the Exception.

Solution is to remove the single quotes in the Query around question mark

Equal symbol expected Struts Error

org.apache.jasper.JasperException: *********.jsp equal symbol expected

If you get this error while using struts..
It could be because you are trying to nest two struts tags..
e.g. I was using something like this..
") />

Also check out this link which gives a more detailed explanation

How to print PreparedStatement ?

Hi,

I usually felt the need to view the full query formed after substituting the '?' with their values in a PreparedStatement. I found a solution at JavaWorld

One more blog

Hi, I think this blog might prove useful to someone unlike my other blog which contains nothing but 100% crap..