toString in error message

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaDescriptorResolver.java

@@ -419,7 +419,7 @@ public class JavaDescriptorResolver {
 
     static void checkPsiClassIsNotJet(PsiClass psiClass) {
         if (psiClass instanceof JetJavaMirrorMarker) {
-            throw new IllegalStateException("trying to resolve fake jet PsiClass as regular PsiClass");
+            throw new IllegalStateException("trying to resolve fake jet PsiClass as regular PsiClass: " + psiClass);
         }
     }
 

compiler/jet.as.java.psi/src/org/jetbrains/jet/asJava/JetLightClass.java

@@ -209,4 +209,13 @@ public class JetLightClass extends AbstractLightClass implements JetJavaMirrorMa
     public Icon getElementIcon(final int flags) {
         return PsiClassImplUtil.getClassIcon(flags, this);
     }
+
+    @Override
+    public String toString() {
+        try {
+            return JetLightClass.class.getSimpleName() + ":" + getQualifiedName();
+        } catch (Throwable e) {
+            return JetLightClass.class.getSimpleName() + ":" + e.toString();
+        }
+    }
 }