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/* ******************************* */
class PDomainEnum {
public static final int PDPoint = 0;
public static final int PDLine = 1;
}

class PDomain {
PDomainEnum type;

public void within(type) {
switch(type) {
case PDPoint:
break;
case PDLine:
break;
default:
break;
}
}
}
/* ************************** */
The above is a not a completed program but just to show
something.I want to create an enum PDomainEnum,it has two variable
PDPoint and PDLine.In PDomain,I define an object of PDomainEnum
type.The most important thing that I want to do is use the switch( ) to
select statement.I know switch not allow the non-int type in it.But I
can't find a method to implement the selection statement.Could you give
me some advice?Addtional,I'm using J2SE 1.4.2,and has some reason I
can't not use J2SE1.5.

The switch statement is just a convenient way of using nested if-else
statements

Bruce Sam wrote:
> /* ******************************* */
> class PDomainEnum {
> public static final int PDPoint = 0;
> public static final int PDLine = 1;

> }
>
> class PDomain {
> PDomainEnum type;
>
> public void within(type) {
> switch(type) {
> case PDPoint:
> break;
> case PDLine:
> break;
> default:
> break;
> }
> }
> }
> /* ************************** */
> The above is a not a completed program but just to show
> something.I want to create an enum PDomainEnum,it has two variable
> PDPoint and PDLine.In PDomain,I define an object of PDomainEnum
> type.

This is the problem, you should be defining an int, see below.

The most important thing that I want to do is use the switch( ) to
> select statement.I know switch not allow the non-int type in it.But I
> can't find a method to implement the selection statement.Could you give
> me some advice?Addtional,I'm using J2SE 1.4.2,and has some reason I
> can't not use J2SE1.5.
>

Your problem is that the 'within' method takes an instance of
PDomainEnum Class. Yet the PDomainEnum class is not your enum, but just
the class where the enums PDPoint & PDLine are defined.

so, change the signature of the 'within()' method to accept an 'int' and
call it like this.

PDomain p = new PDomain()

p.within(PDomainEnum.PDLine);



Having said all of this, your 'enums' are just static int's. Which is
fine, but very crude. Have a google for the Type-Safe enum idiom.

Also, google for 'refactoring replace conditional'.

One of the first links should be...

http://www.refactoring.com/catalog/r...ymorphism.html