Bugzilla – Full Text Bug Listing
| Summary: | [1.5][compiler] Ambiguous method error because methods don't override in eclipse | ||
|---|---|---|---|
| Product: | [Eclipse Project] JDT | Reporter: | Markus Keller <markus.kell.r> |
| Component: | Core | Assignee: | Philipe Mulet <philippe_mulet> |
| Status: | CLOSED FIXED | QA Contact: | |
| Severity: | minor | ||
| Priority: | P3 | CC: | kent_johnson |
| Version: | 3.1 | ||
| Target Milestone: | 3.1 RC2 | ||
| Hardware: | PC | ||
| OS: | Windows XP | ||
| Whiteboard: | |||
Changing Ex to be:
class Ex<C> extends Top<C> {
@Override <M> void method(C cEx, M mEx) { System.out.println("Ex"); }
}
is accepted by both Eclipse & javac.
IMethodBinding#overrides() must have a bug if its not accepting this case.
This case works 'properly' as it reports the unchecked warning:
class Try {
public static void main(String[] args) {
new Ex().method2(new Integer(1));
}
}
class Top<TC> {
<TM> void method2(TM mTop) { System.out.println("Top"); }
}
class Ex<C> extends Top<C> {
@Override <M> void method2(M mEx) { System.out.println("Ex"); }
}
Here is the full case, where we currently fail the 2 messages sends with type
args (all 4 should be unchecked warnings):
class Try {
public static void main(String[] args) {
Ex ex= new Ex();
ex.method("Eclipse1", new Integer(1));
ex.method2(new Integer(1));
ex.method3(new Integer(1));
ex.method4(new Integer(1));
}
}
class Top<TC> {
<TM> void method(TC cTop, TM mTop) { System.out.println("Top"); }
<TM> void method2(TM mTop) { System.out.println("Top"); }
void method3(TC cTop) { System.out.println("Top"); }
<TM> void method4(TC cTop) { System.out.println("Top"); }
}
class Ex<C> extends Top<C> {
@Override <M> void method(C cEx, M mEx) { System.out.println("Ex"); }
@Override <M> void method2(M mEx) { System.out.println("Ex"); }
@Override void method3(C cEx) { System.out.println("Ex"); }
@Override <M> void method4(C cEx) { System.out.println("Ex"); }
}
This is only a problem with Raw types, this case works fine:
class Try {
public static void main(String[] args) {
Ex<String> ex= new Ex<String>();
ex.method("Eclipse1", new Integer(1));
ex.method2(new Integer(1));
ex.method3("Eclipse1");
ex.method4("Eclipse1");
}
}
class Top<TC> {
<TM> void method(TC cTop, TM mTop) { System.out.println("Top"); }
<TM> void method2(TM mTop) { System.out.println("Top"); }
void method3(TC cTop) { System.out.println("Top"); }
<TM> void method4(TC cTop) { System.out.println("Top"); }
}
class Ex<C> extends Top<C> {
@Override <M> void method(C cEx, M mEx) { System.out.println("Ex"); }
@Override <M> void method2(M mEx) { System.out.println("Ex"); }
@Override void method3(C cEx) { System.out.println("Ex"); }
@Override <M> void method4(C cEx) { System.out.println("Ex"); }
}
Added MethodVerify test061 & 62. Needs to be uncommented when fix is released. this.tiebreakMethod = this.isRaw ? this : new ParameterizedGenericMethodBinding (this.originalMethod, (RawTypeBinding)null, this.environment); Tests enabled. Fix released for integration. Verified for 3.1 RC2 using build I20050610-0010 Verified in I20050610-1200. |
N20050609-0010 Javac 1.5.0_03-b07 compiles this code and makes Ex#method(..) override Top#method(). Eclipse rejects the first call to ex.method(..) with this error: "The method method(Object, Object) is ambiguous for the type Ex". IMethodBinding#overrides(..) says that Ex#method(..) does not override Top#method(). public class Try { public static void main(String[] args) { Ex ex= new Ex(); ex.method("Eclipse1", new Integer(1)); Top top= ex; top.method("Eclipse2", new Integer(2)); } } class Top<TC> { <TM> void method(TC cTop, TM mTop) { System.out.println("Top"); } } class Ex<C> extends Top<C> { <M> void method(C cEx, M mEx) { System.out.println("Ex"); } } When I change Ex to ... class Ex<C extends String> extends Top<C> { <M extends Integer> void method(C cEx, M mEx) { System.out.println("Ex"); } } ... then the two compilers agree that the methods don't override and accept the program.