// Assumes targetKinds and E are sensible.
private static <E extends Element> List<E> listFilter(
Iterable<? extends Element> elements, Set<ElementKind> targetKinds, Class<E> clazz) {
List<E> list = new ArrayList<E>();
for (Element e : elements) {
if (targetKinds.contains(e.getKind())) list.add(clazz.cast(e));
}
return list;
}
// Assumes targetKinds and E are sensible.
private static <E extends Element> Set<E> setFilter(
Set<? extends Element> elements, Set<ElementKind> targetKinds, Class<E> clazz) {
// Return set preserving iteration order of input set.
Set<E> set = new LinkedHashSet<E>();
for (Element e : elements) {
if (targetKinds.contains(e.getKind())) set.add(clazz.cast(e));
}
return set;
}
private boolean isInstanceOf(TypeMirror typeMirror, Class type) {
if (!(typeMirror instanceof DeclaredType)) {
return false;
}
if (typeMirror.toString().startsWith(type.getName())) {
return true;
}
DeclaredType declaredType = (DeclaredType) typeMirror;
TypeElement typeElement = (TypeElement) declaredType.asElement();
for (TypeMirror iface : typeElement.getInterfaces()) {
if (isInstanceOf(iface, type)) {
return true;
}
}
return isInstanceOf(typeElement.getSuperclass(), type);
}
/**
* Returns an object cast to the specified type.
*
* @throws NullPointerException if the object is {@code null}
* @throws IllegalArgumentException if the object is of the wrong type
*/
private static <T> T cast(Class<T> clazz, Object o) {
if (!clazz.isInstance(o)) throw new IllegalArgumentException(o.toString());
return clazz.cast(o);
}