Java interface as method arg question.

Hello,
Imagine that I have the following two interfaces and their associated classes:
AI, AC, FooI, FooC
where AC and FooC implements the interfaces AI and AC respectively. Assume than that FooI has contains only the following method:
public void doIt(AI arg);
So far so good. Now assume that FooC attempts to implement the method in it's interface like so:
public void doIt(AC arg);
The java compiler complains thusly:
C:\moment\javatest>javac AC.java AI.java FooC.java FooI.java
FooC.java:1: FooC should be declared abstract; it does not define doIt(AI) in FooC
public class FooC implements FooI
I was surprised by this result. Since AC honors AIs contract, why is the compiler complaining. If someone could explain the reasoning behind the error, I'd really appreciate it. Thanks in advance.
-exits

AC may be an implementation of AI, but not every implementation of AI is AC.
The FooI interface is essentially insisting that the method work on every implemenation of AI. If you create a method that works only on a particular subset of AIs, namely ACs, then you haven't really implemented the method as specified.

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"Eric Sundberg" <[email protected]> wrote in message
news:[email protected]..
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[http://forum.java.sun.com/thread.jspa?threadID=5292343]
[http://forum.java.sun.com/thread.jspa?threadID=5283461]
[http://forum.java.sun.com/thread.jspa?threadID=5283412]
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Hi All,
I could able to work this one out now !!!
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Could not convert from java interface to interface type wsdl ??

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I followed the case closely (with the same name of classes, methods, etc), but still get the error: “Could not convert from java interface to interface type wsdl.Exception=nl.amis.calculator.Calculator”. I created a Java class to test the lookup and function correctly. However, when I try to wire a Mediator to this Reference, I run into an Interface Conversion Error. I’ve included the line javaInterface = “nl.amis.calculator.Calculator” in file composite.xml, but still get error. Could you help me?

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I find Java interface is quite good concept, but some expert mentioned in some article, "Don't over use it".
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Java interface as method arg question.

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