Thu, 30 Jul 2009 10:29:53 +0100
6827648: Extremely slow compilation time for visitor pattern code + generics
Summary: Javac unnecessarily recomputates type-substitutions multiple times
Reviewed-by: jjg
1 /*
2 * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 */
24 /*
25 * @test
26 * @bug 4916650
27 * @summary wildcards versus recursive F-bounds
28 * @author Peter von der Ahe
29 *
30 * @compile Capture5.java
31 */
33 package capture5;
35 interface R<T extends R<T>> {}
36 class A implements R<A> {}
37 class B<T> implements R<B<T>> {}
38 class C implements R<C> {}
40 class Recursive {
41 <t> t choose(t x, t y) {
42 return x;
43 }
44 void f(boolean b1, boolean b2, boolean b3, A a, B<String> b, C c) {
45 R<? extends R<? extends R<? extends R<? extends R<?>>>>> r = null;
46 r = b2 ? a : b;
47 r = b1 ? (b2 ? a : b) : (b3 ? b : c);
48 r = choose(a,c);
49 r = choose(choose(a,b), choose(b,c));
50 }
51 }