Trouble with factory method - unhandled exception type Exception

Hi!

I have a simple factory method:

Code:

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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 );               
 
        }
 
}

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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:

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

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What's wrong with the code ?

Best wishes, Desmond

Quote:

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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

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Code:

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public class FactoryTest {
    public static void main(String[] args) {
        // The ComputerFactory.[i]create[/i] 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 }

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