Why can assignment from one type to the same need checking?

Question

I'm running IntelliJ's Code Analyzer (IntelliJ 11.1.4) on a class and am getting this warning:

Unchecked assignment: 'java.util.List' to 'java.util.List '

The code it complains about is:

List<String> targetDocumentIds = pepperWorkflowInstance.getTargetDocumentIds();

For reference:

public class PepperWorkflowInstance<T extends PepperWorkflowInstanceData> implements Serializable {

   private List<String>            targetDocumentIds = new ArrayList<String>();
   ...
   public List<String> getTargetDocumentIds() {
      return targetDocumentIds;
   }
   ...
}

So the types match... so why would I need to 'check' the assignment?

Answer 1

Make sure that pepperWorkflowInstance has parameter:

pepperWorkflowInstance = new PepperWorkflowInstance<SomeClass>();

See IDEA-6254.