Problems creating a hyperlink

I'm trying to create a hyperlink on a report and I keep getting a ClassCastException. When saving the design file it seems to be trying to cast the Expression as a String. If I create a hyperlink using the report designer it seems to work fine. Here's some example code of what I'm doing:

ActionHandle actionHandle = dataItemHandle.setAction(StructureFactory.createAction()); actionHandle.setLinkType(DesignChoiceConstants.ACTION_LINK_TYPE_HYPERLINK);
actionHandle.setTargetWindow(DesignChoiceConstants.TARGET_NAMES_TYPE_BLANK);
actionHandle.setURI("'http://www.google.com'");

And finally here's the exception:

java.lang.ClassCastException: org.eclipse.birt.report.model.api.Expression cannot be cast to java.lang.String
at org.eclipse.birt.report.model.util.BoundColumnsMgr.dealAction(BoundColumnsMgr.java:604)

Any suggestions?

Find more posts tagged with

Comments

mwilliams

Hi Cain,

Try putting a single quote around a double quote in the function, like:

actionHandle.setURI('"http://www.google.com"');

This may be the reason for your issue. Let me know.

Cain

Sorry I made an error in the above post and corrected it. It should have been actionHandle.setURI("'http://www.google.com'"); 
 
Here's the line of code it is failing on. The method is in the BoundColumnsMgr class: 
 
<pre class='_prettyXprint _lang-auto _linenums:0'>
private void dealAction( ReportItem element, Module module, Action action )
{
if ( action == null )
return;
String value = (String) action.getProperty( module, Action.URI_MEMBER );
...
}
</pre>
 
What's happening is for whatever reason action.getProperty() is returning an Expression rather than a String. So somewhere along the line even though I set the URI as a String it get converted to an Expression, thus causing the ClassCastException. If the line of code looked like this: 
 
String value = action.getProperty( module, Action.URI_MEMBER ).toString(); 
 
Then it would work fine. Obviously an assumption is made that that propery Action.URI_MEMBER will always return a String when in fact this is not the case. What I don't understand is why the BIRT Report Designer works fine yet I can't do it through the API. I must be doing something wrong but I can't find any example code. 
 
UPDATE: 
 
I tried setting the action property manually as a String, and yet it still fails: 
 
Action action = StructureFactory.createAction(); 
action.setProperty(Action.URI_MEMBER, "'http://www.google.com'"); 
dataItemHandle.setAction(action); 
 
Once again even though I set a String it gets converted to an Expression at some unknown point.

mwilliams

Cain,

Have you tried just doing the following?

Action action = StructureFactory.createAction();
action.setURI("http://www.google.com");
dataItemHandle.setAction(action);

Let me know.

Cain

Yes I did that and it wasn't working either.

I found the solution to the problem by debugging the report designer to see what it was doing different. It turns out it all came down to the version not being set on the report design. It seems that BIRT will only apply a version number to a report design once it has been saved. For whatever reason when no version number is set the code takes a different execution path and doesn't go to the code that throws the ClassCastException.

So I "solved" the problem by saving the report design to an output stream after creating it so a version number would be injected.

mwilliams

I'm glad a solution was found!

billnage

Hey, i know this thread is long dead but I had the same problem with ClassCastException and this was the only thread coming up on-line. I thought I should probably post my solution for people in the future hitting this issue. 
 
My workaround is this: 
<pre class='_prettyXprint _lang-auto _linenums:0'>
org.eclipse.birt.report.model.api.elements.structures.Action action = StructureFactory.createAction();
ActionHandle actionHandle = labelHandle.setAction(action);
actionHandle.setLinkType(DesignChoiceConstants.ACTION_LINK_TYPE_HYPERLINK);
actionHandle.setTargetWindow("_self");
labelHandle.setOnPrepare("this.getAction().URI = \"'"+"mywebsite.co.uk"+"'\";");
</pre>
 
Most of the hyperlink is created in Java. But the URI is set via Javascript later on in the report generation. Shouldn't have to be done like this in my opinion but the only decent workaround I could find.

mwilliams

Thanks for sharing! If you ever have any BIRT questions, let us know! We'll try to help!