[CAUSEWAY-3013] [Wicket Viewer] ComponentHintKey can cause NPE

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.0-M7
• Fix Version/s: 2.0.0-M8
• Component/s: Viewer Wicket
• Assignee: Andi Huber
• Reporter: Miklós Győrfi
• Created: 22/Apr/22 07:54
• Updated: 18/Mar/23 12:03
• Resolved: 22/Apr/22 12:22

Description

There is two method to access key value in ComponentHintKey  according to the getKey() method: accessing the component directly if exists, or the componentProvider.  But componentProvider is transient: after the serialization/deserialization cycle it can not be accessed, causing NullPointerException in getKey(). (Wicket viewer caches the page, so serialization is a must)

Solution: gain access to the component directly on serialization:

 

private void writeObject(ObjectOutputStream oos)
        throws IOException {
    if (componentProvider != null && component == null) {
        try {
            component = componentProvider.get();
        } catch (Exception ignored) {
// Maybe some log is necessary or throw the error
        }
    }
    oos.defaultWriteObject();
} 

 

Issue Links

• Is contained by: CAUSEWAY-3005 [Wicket Viewer] DataRowToggle might throw after issuing a Blob Download