一个班级的所有超班级

Question

I have a class that extends to another class and that class extends to another class.

class 1 extends class 2 
class 2 extends class 3 
class 3 extends class 4 
class 4 extends class 5 
class 5 extends class 6 

Now I want to find all super classes of class 1.

Anyone know how I could do that in java?

Answer 1

Use Class.getSuperClass() to traverse the hierarchy.

Class C = getClass();
while (C != null) {
  System.out.println(C.getName());
  C = C.getSuperclass();
}

Answer 2

You can use getSuperclass() up to the Object .

But read the doc first to understand what it returns in the case of interfaces etc. There are more methods to play with on the same page.

Answer 3

As a variation, with a tight loop, you can use a for loop instead:

for (Class super_class = target_class.getSuperclass();
     super_class != null;
     super_class = super_class.getSuperclass())
  // use super class here

Answer 4

从Class1的实例开始递归调用getSuperclass ，直到到达Object 。

Answer 5

Use reflection:

public static List<Class> getSuperClasses(Object o) {
  List<Class> classList = new ArrayList<Class>();
  Class clazz = o.getClass();
  Class superclass = clazz.getSuperclass();
  classList.add(superclass);
  while (superclass != null) {   
    clazz = superclass;
    superclass = class.getSuperclass();
    classList.add(superclass);
  }
  return classList;
}

Answer 6

The other answers are right about using Class.getSuperclass() . But you have to do it repeatedly. Something like

Class superClass = getSuperclass();
while(superClass != null) {
    // do stuff here
    superClass = superClass.getSuperclass();
}