Java Questions

DriverManager is a class in java.sql package. It is the basic service for managing a set of JDBC drivers.

Static member class is a class defined inside outer class with static modifier.

EX:

Class A {  //top level class or outer class

    .....

    static class B {  //static member class

    }

   .....

}

- By using method overriding a sub class can change the definition of super class method.

- By using overriding a sub class can modify the functionality of the super class.

Various elements of OOP are:

• Object

• Class

• Method

• Encapsulation

• Information Hiding

• Inheritance

• Polymorphism

boolean isDirectory();

If constructor opens the file 

finalize() method closes that file.

If constructor opens the connection 

finalize() method closes that connection.

To perform finalization operation we must overriding finalize method.

A static initializer block is a block of code that declares with the static keyword. It normally contains the block of code that must execute at the time of class loading. The static initializer block will execute only once at the time of loading the class only.

Path contains path of .exe files(commands).

Classpath contains path of packages. packages can be stored in folder or .jar files