Error: 'void' type not allowed here

[sudipto shekhar]

Hi, my code is :

class Car
{
public void displayCar()
{
System.out.println("Displaying Car");
}
public void getName()
{
System.out.println("This is a car");
}
}
class Sumo extends Car
{
CarParts cp;
Sumo s;
 
public Sumo()
{
Sumo s=new Sumo();
 
cp=new CarParts();
 
cp.getTyre(s);
 
}
 
public void displayCar()
{
System.out.println("Displaying Sumo");
}
 
public void getName()
{
System.out.println("Tata Sumo");
}
 
public static void main(String a[])
{
new Sumo();
}
 
}
 
class CarParts
{
public void getTyre(Car c)
{
System.out.println("New Tyre for"+c.getName());
}
}
 

The error which I get upon compiling is:

D:\sudipto nw\Sumo.java:56: 'void' type not allowed here
System.out.println("New Tyre for"+c.getName());
^
1 error


I just want to print the name of the car which invoked the getTyre() method.
The code works fine if the return type of the method getName() is changed to String.
This error is a new one for me.
Is there any other way to do this,in a more simpler way?



[ September 20, 2008: Message edited by: Sudipto Shekhar ]

[Seetharaman Venkatasamy]

you can not do this

   
 
System.out.println("New Tyre for"+c.getName());
 

because method return type is Void ... you trying to print valueless thing right?...thats wat the error is ..

Hope This Helps

[sudipto shekhar]

So it is all about printing,right?
Fine.

Thank you.

[Campbell Ritchie]

No, it is not at all about printing.

The error is that a getXXX method usually returns a reference to XXX. So your getName() method ought to have String as its return type and should return the variable in question. Single statement in the method, nothing else. No print statements in the getXXX method (unless you need them for debugging).

Correct that, and your print method will work nicely.

[sudipto shekhar]

Yes, according to OO 'get' should return some value!
But here I don't want to return something.

All I want to do is when the getName() is called,
it prints the name on the output stream.

So why do I need a method returning a value?

[Seetharaman Venkatasamy]

Originally posted by Sudipto Shekhar:
All I want to do is when the getName() is called,
it prints the name on the output stream.
So why do I need a method returning a value?

what about this ?

   
 
String getName(){
return "print";
}
 
then  you  print   or  else
//As  per  your  point  of  view
void getName(){
System.out.println("print");
}
then  inside  main()
new  XXX().getName();
 

 

Hope This Helps

[sudipto shekhar]

I am sorry I did not get you.

[fred rosenberger]

when you say
System.out.println("New Tyre for"+<something>) ;


you are saying "take this string literal 'New Tyre for', and concatenate it with the string..." and then you NEED A STRING.

you can have a string literal, a reference to a string, or a method that returns a string. Those are your only options.

What you have after the '+' is none of those three things.

your options are to change what is there, change what the method returns, or get rid of the "+ <something>" all together. it sounds like what you want would be along the lines of

System.out.print("New Tyre for");
c.getName();

NOTE: Having a "getXXX" method that does not GET the value, but instead PRINTS the value is a poor choice. If someone comes along later and sees a method called "getXXX", they will assume it does what the convention says, and returns the value, not print it. I would encourage you to either a) change the method to return a string, or b) change the method name to be "printXXX".
[ September 21, 2008: Message edited by: fred rosenberger ]

[sudipto shekhar]

Thank You

[Santhi Bharath]

hi,

as i am a novice,i am not sure about my self.

but, how about this one.

object_name.getClass().getName();

in your case

c.getClass().getName();

[Campbell Ritchie]

That will return a name, Santhi Bharat, but almost certainly not the name wanted.
[edit]Add: That instruction will get the name of the class that object was created from, not the name field in this class.
The custom is to use (??public) String getName() which returns the name field.[/edit]
[ September 21, 2008: Message edited by: Campbell Ritchie ]

[Santhi Bharath]

thank you for your reply.i can understand now what i have sent and what you have told

[Campbell Ritchie]

You're welcome

[sudipto shekhar]

Thank you all.

[Campbell Ritchie]

You're welcome