6548436: Incorrect inconvertible types error

Types.rewrite quantifiers should cope with captured type-variables properly

Reviewed-by: jjg

langtools/src/share/classes/com/sun/tools/javac/code/Types.java

@@ -3367,33 +3367,67 @@ public class Types {
      * quantifiers) only
      */
     private Type rewriteQuantifiers(Type t, boolean high, boolean rewriteTypeVars) {
-        ListBuffer<Type> from = new ListBuffer<Type>();
+        return new Rewriter(high, rewriteTypeVars).rewrite(t);
-        ListBuffer<Type> to = new ListBuffer<Type>();
+    }
-        adaptSelf(t, from, to);
+
-        ListBuffer<Type> rewritten = new ListBuffer<Type>();
+    class Rewriter extends UnaryVisitor<Type> {
-        List<Type> formals = from.toList();
+
-        boolean changed = false;
+        boolean high;
-        for (Type arg : to.toList()) {
+        boolean rewriteTypeVars;
-            Type bound;
+
-            if (rewriteTypeVars && arg.tag == TYPEVAR) {
+        Rewriter(boolean high, boolean rewriteTypeVars) {
-                TypeVar tv = (TypeVar)arg;
+            this.high = high;
-                bound = high ? tv.bound : syms.botType;
+            this.rewriteTypeVars = rewriteTypeVars;
-            } else {
+        }
-                bound = high ? upperBound(arg) : lowerBound(arg);
+
-            }
+        Type rewrite(Type t) {
-            Type newarg = bound;
+            ListBuffer<Type> from = new ListBuffer<Type>();
-            if (arg != bound) {
+            ListBuffer<Type> to = new ListBuffer<Type>();
-                changed = true;
+            adaptSelf(t, from, to);
-                newarg = high ? makeExtendsWildcard(bound, (TypeVar)formals.head)
+            ListBuffer<Type> rewritten = new ListBuffer<Type>();
-                              : makeSuperWildcard(bound, (TypeVar)formals.head);
+            List<Type> formals = from.toList();
-            }
+            boolean changed = false;
-            rewritten.append(newarg);
+            for (Type arg : to.toList()) {
-            formals = formals.tail;
+                Type bound = visit(arg);
+                if (arg != bound) {
+                    changed = true;
+                    bound = high ? makeExtendsWildcard(bound, (TypeVar)formals.head)
+                              : makeSuperWildcard(bound, (TypeVar)formals.head);
+                }
+                rewritten.append(bound);
+                formals = formals.tail;
+            }
+            if (changed)
+                return subst(t.tsym.type, from.toList(), rewritten.toList());
+            else
+                return t;
+        }
+
+        public Type visitType(Type t, Void s) {
+            return high ? upperBound(t) : lowerBound(t);
+        }
+
+        @Override
+        public Type visitCapturedType(CapturedType t, Void s) {
+            return visitWildcardType(t.wildcard, null);
+        }
+
+        @Override
+        public Type visitTypeVar(TypeVar t, Void s) {
+            if (rewriteTypeVars)
+                return high ? t.bound : syms.botType;
+            else
+                return t;
+        }
+
+        @Override
+        public Type visitWildcardType(WildcardType t, Void s) {
+            Type bound = high ? t.getExtendsBound() :
+                                t.getSuperBound();
+            if (bound == null)
+                bound = high ? syms.objectType : syms.botType;
+            return bound;
         }
-        if (changed)
-            return subst(t.tsym.type, from.toList(), rewritten.toList());
-        else
-            return t;
     }
 
     /**

langtools/test/tools/javac/cast/6548436/T6548436a.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6548436
+ * @summary Incorrect inconvertible types error
+ * @author Maurizio Cimadamore
+ *
+ * @compile T6548436a.java
+ */
+
+public class T6548436a {
+
+    static class Base<E extends Comparable<E>> {}
+
+    static void test(Base<?> je) {
+        Object o = (Base<Integer>)je;
+    }
+}

langtools/test/tools/javac/cast/6548436/T6548436b.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6548436
+ * @summary Incorrect inconvertible types error
+ * @author Maurizio Cimadamore
+ *
+ * @compile T6548436b.java
+ */
+
+public class T6548436b {
+
+    enum E { }
+
+    static void test(Enum<?> o) {
+        Object e = (E)o;
+    }
+}

langtools/test/tools/javac/cast/6548436/T6548436c.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6548436
+ * @summary Incorrect inconvertible types error
+ * @author Maurizio Cimadamore
+ *
+ * @compile T6548436c.java
+ */
+
+public class T6548436c {
+
+    interface A<T extends A<? super T>> { }
+
+    interface B extends A<B> { }
+
+    static void test(A<?> a) {
+        Object o = (B)a;
+    }
+}

langtools/test/tools/javac/cast/6548436/T6548436d.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6548436
+ * @summary Incorrect inconvertible types error
+ * @author Maurizio Cimadamore
+ *
+ * @compile/fail T6548436d.java
+ */
+
+public class T6548436d {
+
+    static class Base<E extends Comparable<E>> {}
+
+    static void test(Base<? extends Double> je) {
+        Object o = (Base<Integer>)je;
+    }
+}