Details
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Type:
Bug
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Status:
Closed
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Priority:
Blocker
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Resolution: Fixed
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Affects Version/s: None
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Fix Version/s: 1.6.5, 1.7-beta-2
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Component/s: Compiler
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Labels:None
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Environment:Windows 7
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Number of attachments :
Description
I have two files:
— A.groovy
package p; public class A<T> { }
—
— B.groovy
package p; class B extends A<String> { }
—
Depending on the order in which they are passed to groovyc, I may get an error:
> groovyc A.groovy B.groovy
works fine.
> groovyc B.groovy A.groovy
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup
failed, B.groovy: 3: The type String is not a valid substitute for the
bounded parameter <T>
@ line 3, column 17.
class B extends A<String> {
^
1 error
This happens because the generics checking is done as part of the resolution phase. From CompilationUnit:
private final SourceUnitOperation resolve = new SourceUnitOperation() { public void call(SourceUnit source) throws CompilationFailedException { List classes = source.ast.getClasses(); for (Iterator it = classes.iterator(); it.hasNext();) { ClassNode node = (ClassNode) it.next(); VariableScopeVisitor scopeVisitor = new VariableScopeVisitor(source); scopeVisitor.visitClass(node); resolveVisitor.startResolving(node, source); GenericsVisitor genericsVisitor = new GenericsVisitor(source); genericsVisitor.visitClass(node); } } };
if the generics check is performed before the types involved (like A) are resolved, you get this problem. The solution is to break that into two phases: resolution and then generics checking (take the last two lines from the resolution phase and move them into a new phase, done after resolution):
/**
* Check generics usage
*/
private final SourceUnitOperation checkGenerics = new SourceUnitOperation() {
public void call(SourceUnit source) throws CompilationFailedException {
List classes = source.ast.getClasses();
for (Iterator it = classes.iterator(); it.hasNext();) {
ClassNode node = (ClassNode) it.next();
GenericsVisitor genericsVisitor = new GenericsVisitor(source);
genericsVisitor.visitClass(node);
}
}
};
then the order doesn't matter.
formatting