Trouble with factory method - unhandled exception type Exception

[desmond5]

Hi!

I have a simple factory method:

Code:

public final class ComputerFactory {
	
	public static Computer create(ComputerType type) throws Exception
	{
			
		switch(type)
		{
			case PC:
				return new CompPC();
			case Mac:
				return new CompMac();
			case Sparc:
				return new CompSparc();
			case Itanium:
				return new CompItanium();		
		}
		
		throw new Exception("No such computer: " + type );		
 
	}
 
}

ComputerType is a enum with 4 items in it (all listen in the switch block).

When I try to create new Computers in another class with the factory method I get an error says: unhandled exception type Excepton:

Code:

comps.add(ComputerFactory.create(ComputerType.PC));

What's wrong with the code ?

Best wishes, Desmond

[hardwired]

Quote:

C:\jexp>javac factorytest.java
factorytest.java:3: unreported exception java.lang.Exception; must be caught or declared to be thrown
String mac = ComputerFactory.create(ComputerType.Mac);
^
1 error

Code:

public class FactoryTest {
    public static void main(String[] args) {
        // The ComputerFactory.create method declares
        // that it throws an Exception. So the caller
        // must be prepared to catch it.
        String mac = null;
        try {
            mac = ComputerFactory.create(ComputerType.Mac);
        } catch(Exception e) {
            System.out.println(e.getClass().getName() + ": " +
                               e.getMessage());
        }
        System.out.println("mac = " + mac);
    }
}

final class ComputerFactory {
    public static String create(ComputerType type) throws Exception {
        switch(type) {
            case PC:      return "new CompPC";
            case Mac:     return "new CompMac";
            case Sparc:   return "new CompSparc";
            case Itanium: return "new CompItanium";		
        }
        throw new Exception("No such computer: " + type );		
    }
}

enum ComputerType { PC, Mac, Sparc, Itanium }