If we want to establish a connection between java application and the database we will the following piece of code.
Connection con= DriverManager.getConnection(“jdbc:odbc:nag”,”nag”,”system”,”manager”);
Where getConnectin() is a static
method from DriverManager class, which can be used to return connection
object.
Basically Connection is an interface, how getConnection() will create an object for Connection interface?
Ans:
Connection is an interface from
java.sql package, for which getConnection(_) was return an anonymous
inner class object of the Connection interface.
Note:-
Anonymous inner class is a nameless
inner class, which can be sued to provide an implementation either for
the interfaces or for abstract classes.
Eg: interface I
{
void m1();
}
Class Outer
{
I i = new I(){
public void m1()
{
}
public void m2()
{
}
}
}
Outer o = new Outer();
o.i.m1(); à correct
o.i.m2(); à wrong
getConnection(_) is a static method from DriverManager class, which will call internally connect() method, this connect() will establish a virtual socket connection in between the java application and the database.
