Description Mirko Raner 2011-03-31 20:19:27 EDT

We're getting an NPE in the Open Model Element dialog when we perform the following steps:

(1) enter some search text in the element name field, and then
(2) remove all text from the element name field, leaving it empty

The error message and stack trace is:

Message: An internal error occurred during: "Calculate result size".

java.lang.NullPointerException
    at org.eclipse.xtext.ui.search.IteratorJob$1.compare(IteratorJob.java:68)
    at org.eclipse.xtext.ui.search.IteratorJob$1.compare(IteratorJob.java:1)
    at java.util.Arrays.mergeSort(Arrays.java:1293)
    at java.util.Arrays.mergeSort(Arrays.java:1282)
    at java.util.Arrays.sort(Arrays.java:1210)
    at java.util.Collections.sort(Collections.java:159)
    at com.google.common.collect.Lists.sortedCopy(Lists.java:214)
    at org.eclipse.xtext.ui.search.IteratorJob.sortedCopy(IteratorJob.java:64)
    at org.eclipse.xtext.ui.search.IteratorJob.run(IteratorJob.java:59)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

We're not sure what exactly is going on here, but it looks like the comparator could use some safety guards in line 68:

    private Collection<IEObjectDescription> sortedCopy(Iterable<IEObjectDescription> list) {
        return Lists.sortedCopy(matches, new Comparator<IEObjectDescription>() {
            public int compare(IEObjectDescription o1, IEObjectDescription o2) {
                int diff = o1.getQualifiedName().compareToIgnoreCase(o2.getQualifiedName());
                if(diff==0) {
                    diff = o1.getEClass().getName().compareToIgnoreCase(o2.getEClass().getName());
                    if(diff==0) {
                        diff = o1.getEObjectURI().toString().compareTo(o2.getEObjectURI().toString());
                    }
                }
                return diff;
            }
        });
    }

There may be a problem with our model in that getName() returns null for some EClasses, but the comparison should probably handle this more gracefully.