Can you declare a constructor inside an abstract class?

Yes, in Java, constructors can be declared inside an abstract class. An abstract class cannot be instantiated directly, but its constructors are called when creating objects of subclasses. This allows initializing common fields and performing shared logic when creating subclasses.

Example:

abstract class Animal {
    String name;

    public Animal(String name) {
        this.name = name;
    }
}

class Dog extends Animal {
    public Dog(String name) {
        super(name);
    }
}