### Question:
BlueprintELResolver extends ELResolver { @Override public Class<?> getCommonPropertyType(ELContext context, Object arg) { return Object.class; }  @Override Object getValue(ELContext context, Object base, Object property); void bindService(JavaDelegate delegate, Map<?, ?> props); void unbindService(JavaDelegate delegate, Map<?, ?> props); void bindTaskListenerService(TaskListener delegate, Map props); void unbindTaskListenerService(TaskListener delegate, Map props); void bindActivityBehaviourService(ActivityBehavior delegate, Map props); void unbindActivityBehaviourService(ActivityBehavior delegate, Map props); @Override boolean isReadOnly(ELContext context, Object base, Object property); @Override void setValue(ELContext context, Object base, Object property,
			Object value); @Override Class<?> getCommonPropertyType(ELContext context, Object arg); @Override Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context,
			Object arg); @Override Class<?> getType(ELContext context, Object arg1, Object arg2);  }### Answer:
@Test public void getCommonPropertyType() { assertThat(resolver.getCommonPropertyType(null, null), isA(Object.class)); }