Description shibin 2007-11-11 13:33:43 EST

Build ID: N20071111-0010

Steps To Reproduce:

The code sample is taken from Java Puzzlers problem 37.
Expected Result: The code should compile fine
Actual Result: ecj reports unhandled exception 

code
----

interface Type1 {
    void f() throws CloneNotSupportedException;
}

interface Type2 {
    void f() throws InterruptedException;
}

interface Type3 extends Type1, Type2 {}


public class Arcane3 implements Type3 {
    public void f() {
        System.out.println("Hello world");
    }
    public static void main(String[] args) {
        Type3 t3 = new Arcane3();
        t3.f();
    }
}

problem
-------
The method f in interface Type3 doesn't throw any exception  so main method needn't handle any exception, but eclipse requires CloneNotSupportedException to be handled.
  
Quoting from the book
"The set of checked exceptions that a method can throw is the intersection of the sets of checked exceptions that it is declared to throw in all applicable types, not the union. As a result, the f method on an object whose static type is Type3 can't throw any checked exceptions at all. Therefore, Arcane3 compiles without error and prints Hello world." 

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