Java reflection get all private fields

Question

I wonder is there a way to get all private fields of some class in java and their type.

For example lets suppose I have a class

class SomeClass {     private String aaa;     private SomeOtherClass bbb;     private double ccc; } 

Now I would like to get all private fields (aaa, bbb, ccc) of class SomeClass (Without knowing name of all fields upfront) and check their type.

Answer 1

It is possible to obtain all fields with the method getDeclaredFields() of Class. Then you have to check the modifier of each fields to find the private ones:

List<Field> privateFields = new ArrayList<>(); Field[] allFields = SomeClass.class.getDeclaredFields(); for (Field field : allFields) {     if (Modifier.isPrivate(field.getModifiers())) {         privateFields.add(field);     } } 

Note that getDeclaredFields() will not return inherited fields.

Eventually, you get the type of the fields with the method Field.getType().