Some of important difference between constructor and method are:
1. Constructors are must be declare with same name as the class name. But there is no such type of requirement in methods; methods can have any arbitrary name in java.
2. Constructors don’t have any return type even “void”. Methods must be declared to return something although it can be “void”.
3. Constructors can’t be called be directly, they are called implicitly when the new keyword creates an object, methods can be called directly on an object that has already been created with new.
4. Constructors are chained and they are called in particular order, there is no such facility for method.
5. Constructors create and initialize object that don’t exist yet, while methods perform operation on objects that already exist.
6. To call constructors in java we are used special keyword “this & super” explicitly, no such thing for method they have own name which can be used to call them.