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Understanding errors

I get 'Internal error cloning object' errors

This is a debug feature to help find potential problems when the application runs clustered. It checks the component graphs to make sure everything is serializable (which is required for clustering).

If clustering support is not needed, these checks can be disabled by doing getDebugSettings().setSerializeSessionAttributes(false); in the application.init()

Also, if the configuration parameter in the web.xml is set to DEPLOYMENT, these checks are disabled.

Answer provided courtesy Igor Vaynberg

Wicket architecture

What about performance and scalability?

Wicket performance is actually quite good under stress. Remember though that in many real-world application your bottleneck will be in business or database layer.

Wicket benchmark can be found here: wicket-1.3.x-benchmark.

You should also search wicket-user mailing list for performance and scalability or simply use performance-scalability-tipsas your starting point.

Versioning

Wicket architecture

What about performance and scalability?

Wicket performance is actually quite good under stress. Remember though that in many real-world application your bottleneck will be in business or database layer.

Wicket benchmark can be found here: wicket-1.3.x-benchmark.

You should also search wicket-user mailing list for performance and scalability or simply use performance-scalability-tipsas your starting point.

Versioning

Wicket stores versions of pages to support the browser's back button. Because this concept is difficult Wicket stores versions of pages to support the browser's back button. Because this concept is difficult to understand, we'll present a simple use case that describes the problem and how versioning helps.

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getRequestCycle().onRuntimeException(new MyErrorPage(), theException);

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How do I add/display errors (like Page Expired)?

Normally all that is needed to display errors in a page is to call the "error" method in the WebPage:

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getSession().error(message);
throw new RestartResponseException(MyErrorPage.class, optionalPageParameters);

// it may be tempting to do the following, but it should not be done:
// error(message);
// setResponsePage(MyErrorPage.class);
:
// error(message);
// setResponsePage(MyErrorPage.class);

I get 'Internal error cloning object' errors

This is a debug feature to help find potential problems when the application runs clustered. It checks the component graphs to make sure everything is serializable (which is required for clustering).

If clustering support is not needed, these checks can be disabled by doing getDebugSettings().setSerializeSessionAttributes(false); in the application.init()

Also, if the configuration parameter in the web.xml is set to DEPLOYMENT, these checks are disabled.

Answer provided courtesy Igor Vaynberg

How can I have images/files uploaded to and downloaded from my wicket app?

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