public void checkValid(String propertyName) {
   Preconditions.checkNotBlank(propertyName, "propertyName cannot be empty");
   Preconditions.checkArgument(
       propertyNames.contains(propertyName),
       MessageFormat.format(
           "No such property ''{0}''", PropertyUtils.shortDescription(beanClass, propertyName)));
 }
 private void addGroupedViewAttributeMapping(
     GroupedViewAttributeFactory<ViewType> factory, String... attributeNames) {
   org.robobinding.util.Preconditions.checkNotBlank(
       "attributeNames cannot be empty or contain any empty attribute name", attributeNames);
   groupedViewAttributeMappings.put(
       attributeNames, viewAttributeBinderFactory.binderFactoryFor(factory));
 }
  public void map(ChildAttributeResolver resolver, String attribute) {
    Preconditions.checkNotBlank(attribute, "Attribute cannot be empty");
    Preconditions.checkNotNull(resolver, "Resolver cannot be null");

    childAttributeResolvers.put(attribute, resolver);
  }
 private void checkAttributeNameNotEmpty(String attributeName) {
   org.robobinding.util.Preconditions.checkNotBlank(
       attributeName, "attributeName cannot be empty");
 }
 private void checkFactoryNotNull(Object factory) {
   Preconditions.checkNotNull(factory, "factory cannot be null");
 }
 private void checkViewAttributeClassNotNull(Class<?> viewAttributeClass) {
   Preconditions.checkNotNull(viewAttributeClass, "viewAttributeClass cannot be null");
 }