Getting first parent's fields via reflection

Question

I'm trying to get the fields and values of my object's first parent. My current code is this:

Class<? extends Object> cls = obj.getClass();
Field[] fields = cls.getDeclaredFields();
for ( Field field : fields )
{
    String fieldName = field.getName();
    String fieldValue = field.get(obj);
}

My class structure is similar to this:

class A
{
    int x;
}

class B extends A
{
    int y;
}

class C extends B
{
    int z;
}

Now, I pass a C object to the method and I want to get all fields from C and B, but not from A. Is there a way to do this (using reflection, I don't want to implement other methods)?

Answer 1

Luchian, use the getSuperclass() method to obtain a reference to a Class object that represents a superclass type of the object in question. After that it is going to be easy for you to get fields the same way you do in your example.

Answer 2

Create a method

public static void printFieldsFor(Class cls, Object obj) {
  Field[] fields = cls.getDeclaredFields();
  for ( Field field : fields ) {
    String fieldName = field.getName();
    String fieldValue = field.get(obj);
  }
}

printFieldsFor(object.getClass(), obj);
printFieldsFor(object.getClass().getSuperclass(), obj);

or use a loop

for(Class cls = object.getClass(); 
    cls!=null && cls!=A.class; 
    cls = cls.getSuperclass()) {
  for(Field field : cls.getDeclaredFields()) {
     String fieldName = field.getName();
     String fieldValue = field.get(obj);
     // do something with the field.
  }
}