Mercurial > jdk8-mips64-public > langtools / changeset

     1.1 --- a/src/share/classes/com/sun/tools/javac/comp/Infer.java	Fri Apr 18 23:50:41 2014 +0100
     1.2 +++ b/src/share/classes/com/sun/tools/javac/comp/Infer.java	Fri Apr 18 23:58:05 2014 +0100
     1.3 @@ -516,6 +516,32 @@
     1.4          /** max number of incorporation rounds */
     1.5          static final int MAX_INCORPORATION_STEPS = 100;
     1.6  
     1.7 +    /* If for two types t and s there is a least upper bound that is a
     1.8 +     * parameterized type G, then there exists a supertype of 't' of the form
     1.9 +     * G<T1, ..., Tn> and a supertype of 's' of the form G<S1, ..., Sn>
    1.10 +     * which will be returned by this method. If no such supertypes exists then
    1.11 +     * null is returned.
    1.12 +     *
    1.13 +     * As an example for the following input:
    1.14 +     *
    1.15 +     * t = java.util.ArrayList<java.lang.String>
    1.16 +     * s = java.util.List<T>
    1.17 +     *
    1.18 +     * we get this ouput:
    1.19 +     *
    1.20 +     * Pair[java.util.List<java.lang.String>,java.util.List<T>]
    1.21 +     */
    1.22 +    private Pair<Type, Type> getParameterizedSupers(Type t, Type s) {
    1.23 +        Type lubResult = types.lub(t, s);
    1.24 +        if (lubResult == syms.errType || lubResult == syms.botType ||
    1.25 +                !lubResult.isParameterized()) {
    1.26 +            return null;
    1.27 +        }
    1.28 +        Type asSuperOfT = types.asSuper(t, lubResult.tsym);
    1.29 +        Type asSuperOfS = types.asSuper(s, lubResult.tsym);
    1.30 +        return new Pair<>(asSuperOfT, asSuperOfS);
    1.31 +    }
    1.32 +
    1.33      /**
    1.34       * This enumeration defines an entry point for doing inference variable
    1.35       * bound incorporation - it can be used to inject custom incorporation
    1.36 @@ -651,6 +677,53 @@
    1.37              }
    1.38          },
    1.39          /**
    1.40 +         * Given a bound set containing {@code alpha <: P<T>} and
    1.41 +         * {@code alpha <: P<S>} where P is a parameterized type,
    1.42 +         * perform {@code T = S} (which could lead to new bounds).
    1.43 +         */
    1.44 +        CROSS_UPPER_UPPER() {
    1.45 +            @Override
    1.46 +            public void apply(UndetVar uv, InferenceContext inferenceContext, Warner warn) {
    1.47 +                Infer infer = inferenceContext.infer();
    1.48 +                List<Type> boundList = uv.getBounds(InferenceBound.UPPER);
    1.49 +                List<Type> boundListTail = boundList.tail;
    1.50 +                while (boundList.nonEmpty()) {
    1.51 +                    List<Type> tmpTail = boundListTail;
    1.52 +                    while (tmpTail.nonEmpty()) {
    1.53 +                        Type b1 = boundList.head;
    1.54 +                        Type b2 = tmpTail.head;
    1.55 +                        if (b1 != b2) {
    1.56 +                            Pair<Type, Type> commonSupers = infer.getParameterizedSupers(b1, b2);
    1.57 +                            if (commonSupers != null) {
    1.58 +                                List<Type> allParamsSuperBound1 = commonSupers.fst.allparams();
    1.59 +                                List<Type> allParamsSuperBound2 = commonSupers.snd.allparams();
    1.60 +                                while (allParamsSuperBound1.nonEmpty() && allParamsSuperBound2.nonEmpty()) {
    1.61 +                                    //traverse the list of all params comparing them
    1.62 +                                    if (!allParamsSuperBound1.head.hasTag(WILDCARD) &&
    1.63 +                                        !allParamsSuperBound2.head.hasTag(WILDCARD)) {
    1.64 +                                        isSameType(inferenceContext.asUndetVar(allParamsSuperBound1.head),
    1.65 +                                            inferenceContext.asUndetVar(allParamsSuperBound2.head), infer);
    1.66 +                                    }
    1.67 +                                    allParamsSuperBound1 = allParamsSuperBound1.tail;
    1.68 +                                    allParamsSuperBound2 = allParamsSuperBound2.tail;
    1.69 +                                }
    1.70 +                                Assert.check(allParamsSuperBound1.isEmpty() && allParamsSuperBound2.isEmpty());
    1.71 +                            }
    1.72 +                        }
    1.73 +                        tmpTail = tmpTail.tail;
    1.74 +                    }
    1.75 +                    boundList = boundList.tail;
    1.76 +                    boundListTail = boundList.tail;
    1.77 +                }
    1.78 +            }
    1.79 +
    1.80 +            @Override
    1.81 +            boolean accepts(UndetVar uv, InferenceContext inferenceContext) {
    1.82 +                return !uv.isCaptured() &&
    1.83 +                        uv.getBounds(InferenceBound.UPPER).nonEmpty();
    1.84 +            }
    1.85 +        },
    1.86 +        /**
    1.87           * Given a bound set containing {@code alpha == S} and {@code alpha == T}
    1.88           * perform {@code S == T} (which could lead to new bounds).
    1.89           */

     2.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     2.2 +++ b/test/tools/javac/T8029002/MultipleUpperBoundsIncorporationTest.java	Fri Apr 18 23:58:05 2014 +0100
     2.3 @@ -0,0 +1,72 @@
     2.4 +/*
     2.5 + * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
     2.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     2.7 + *
     2.8 + * This code is free software; you can redistribute it and/or modify it
     2.9 + * under the terms of the GNU General Public License version 2 only, as
    2.10 + * published by the Free Software Foundation.
    2.11 + *
    2.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
    2.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    2.14 + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    2.15 + * version 2 for more details (a copy is included in the LICENSE file that
    2.16 + * accompanied this code).
    2.17 + *
    2.18 + * You should have received a copy of the GNU General Public License version
    2.19 + * 2 along with this work; if not, write to the Free Software Foundation,
    2.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    2.21 + *
    2.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    2.23 + * or visit www.oracle.com if you need additional information or have any
    2.24 + * questions.
    2.25 + */
    2.26 +
    2.27 +/*
    2.28 + * @test
    2.29 + * @bug 8029002
    2.30 + * @summary javac should take multiple upper bounds into account in incorporation
    2.31 + * @compile MultipleUpperBoundsIncorporationTest.java
    2.32 + */
    2.33 +
    2.34 +import java.util.ArrayList;
    2.35 +import java.util.List;
    2.36 +
    2.37 +public class MultipleUpperBoundsIncorporationTest {
    2.38 +
    2.39 +    static class TestCase1 {
    2.40 +        interface Task<E extends Exception> {}
    2.41 +
    2.42 +        class Comparator<T> {}
    2.43 +
    2.44 +        class CustomException extends Exception {}
    2.45 +
    2.46 +        class TaskQueue<E extends Exception, T extends Task<E>> {}
    2.47 +
    2.48 +        abstract class Test {
    2.49 +            abstract <E extends Exception, T extends Task<E>> TaskQueue<E, T> create(Comparator<? super T> comparator);
    2.50 +
    2.51 +            void f(Comparator<Task<CustomException>> comp) {
    2.52 +                TaskQueue<CustomException, Task<CustomException>> queue = create(comp);
    2.53 +                queue.getClass();
    2.54 +            }
    2.55 +        }
    2.56 +    }
    2.57 +
    2.58 +    static class TestCase2 {
    2.59 +        public <T, E extends List<T>> E typedNull() {
    2.60 +            return null;
    2.61 +        }
    2.62 +
    2.63 +        public void call() {
    2.64 +            ArrayList<String> list = typedNull();
    2.65 +        }
    2.66 +    }
    2.67 +
    2.68 +    static class TestCase3 {
    2.69 +        interface I extends Iterable<String> {}
    2.70 +
    2.71 +        <T, Exp extends Iterable<T>> Exp typedNull() { return null; }
    2.72 +        I i = typedNull();
    2.73 +    }
    2.74 +
    2.75 +}