17. • //DriveAcar06.java
class Vehicle {
int numberOfWheels ;
boolean hasEngine ;
//constructor
Vehicle() {
numberOfWheels = 6 ;
hasEngine = true ;
System.out.println("A car has been built") ; // (1) notice this line
}
void run() {
System.out.println("I am running") ;
}
}
public class DriveAcar06 {
public static void main(String[] args) {
Vehicle myCar = new Vehicle() ;
System.out.println("mycar has "+myCar.numberOfWheels+"Wheels.") ; // (2)
System.out.println("That mycar has an engin is "+myCar.hasEngine+".") ; // (3)
}
}
19. • //OverloadConstructor.java
class Vehicle {
int numberOfWheels ;
boolean hasEngine ;
//constructor and Overload Constructor
Vehicle() {
numberOfWheels = 6 ;
hasEngine = true ;
System.out.println("A car has been built") ; //notice this line
}
Vehicle(int number, boolean engine) { // (1)
numberOfWheels = number ;
hasEngine = engine ;
System.out.println("A car has been built") ; //notice this line
}
void run() {
System.out.println("I am running") ;
}
}
public class OverloadConstructor {
public static void main(String[] args) {
Vehicle myCar = new Vehicle(4,true) ; // (2)
System.out.println("mycar has "+myCar.numberOfWheels+"Wheels.") ;
System.out.println("That mycar has an engin is "+myCar.hasEngine+".") ;
}
}
20. • //TestThis.java this()
class A {
int a ;
A() {
a=0;
System.out.println("Default constructor") ;
}
A(int i) {
this() ;
a=i;
System.out.println("constructor 1 ") ;
}
A(int i, int j) {
this(i+j) ;
System.out.println("constructor 2 ") ;
21. • }
}
public class DriveAcar06 {
public static void main(String[] args) {
System.out.println("Instantiate x");
A x = new A() ;
System.out.println("Variable a is "+ x.a) ;
System.out.println("Instantiate y ");
A y = new A(5) ;
System.out.println("Variable a is "+ y.a) ;
System.out.println("Instantiate z ");
A z = new A(5,6) ;
System.out.println("Variable a is "+ z.a) ;
}
}
this()
22.
23. • static File System File System
File Access
• File Access Component
• Set Fso= CreateObject("Scripting.FileSystemObject")
• Fso
File Access Component Fso
• Open Text File Method
•
• Object.openTextFile(filename[,iomode][,create][,Format]
•
• Object