GenericOverrideTest.java revision 1481:954541f13717 
1/*
2 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 * @test
26 * @bug 7062745
27 * @summary  Regression: difference in overload resolution when two methods
28 * are maximally specific
29 * @library ../../../lib
30 * @build JavacTestingAbstractThreadedTest
31 * @run main GenericOverrideTest
32 */
33
34import java.net.URI;
35import java.util.Arrays;
36import javax.tools.Diagnostic;
37import javax.tools.JavaFileObject;
38import javax.tools.SimpleJavaFileObject;
39import com.sun.source.util.JavacTask;
40
41public class GenericOverrideTest
42    extends JavacTestingAbstractThreadedTest
43    implements Runnable {
44
45    enum SignatureKind {
46        NON_GENERIC(""),
47        GENERIC("<X>");
48
49        String paramStr;
50
51        private SignatureKind(String paramStr) {
52            this.paramStr = paramStr;
53        }
54    }
55
56    enum ReturnTypeKind {
57        LIST("List"),
58        ARRAYLIST("ArrayList");
59
60        String retStr;
61
62        private ReturnTypeKind(String retStr) {
63            this.retStr = retStr;
64        }
65
66        boolean moreSpecificThan(ReturnTypeKind that) {
67            switch (this) {
68                case LIST:
69                    return that == this;
70                case ARRAYLIST:
71                    return that == LIST || that == ARRAYLIST;
72                default: throw new AssertionError("Unexpected ret kind: " + this);
73            }
74        }
75    }
76
77    enum TypeArgumentKind {
78        NONE(""),
79        UNBOUND("<?>"),
80        INTEGER("<Number>"),
81        NUMBER("<Integer>"),
82        TYPEVAR("<X>");
83
84        String typeargStr;
85
86        private TypeArgumentKind(String typeargStr) {
87            this.typeargStr = typeargStr;
88        }
89
90        boolean compatibleWith(SignatureKind sig) {
91            switch (this) {
92                case TYPEVAR: return sig != SignatureKind.NON_GENERIC;
93                default: return true;
94            }
95        }
96
97        boolean moreSpecificThan(TypeArgumentKind that, boolean strict) {
98            switch (this) {
99                case NONE:
100                    return that == this || !strict;
101                case UNBOUND:
102                    return that == this || that == NONE;
103                case INTEGER:
104                case NUMBER:
105                case TYPEVAR:
106                    return that == this || that == NONE || that == UNBOUND;
107                default: throw new AssertionError("Unexpected typearg kind: " + this);
108            }
109        }
110
111        boolean assignableTo(TypeArgumentKind that, SignatureKind sig) {
112            switch (this) {
113                case NONE:
114                    //this case needs to workaround to javac's impl of 15.12.2.8 being too strict
115                    //ideally should be just 'return true' (see 7067746)
116                    return sig == SignatureKind.NON_GENERIC || that == NONE;
117                case UNBOUND:
118                    return that == this || that == NONE;
119                case INTEGER:
120                case NUMBER:
121                    return that == this || that == NONE || that == UNBOUND;
122                case TYPEVAR:
123                    return true;
124                default: throw new AssertionError("Unexpected typearg kind: " + this);
125            }
126        }
127    }
128
129    public static void main(String... args) throws Exception {
130        for (SignatureKind sig1 : SignatureKind.values()) {
131            for (ReturnTypeKind rt1 : ReturnTypeKind.values()) {
132                for (TypeArgumentKind ta1 : TypeArgumentKind.values()) {
133                    if (!ta1.compatibleWith(sig1)) continue;
134                    for (SignatureKind sig2 : SignatureKind.values()) {
135                        for (ReturnTypeKind rt2 : ReturnTypeKind.values()) {
136                            for (TypeArgumentKind ta2 : TypeArgumentKind.values()) {
137                                if (!ta2.compatibleWith(sig2)) continue;
138                                for (ReturnTypeKind rt3 : ReturnTypeKind.values()) {
139                                    for (TypeArgumentKind ta3 : TypeArgumentKind.values()) {
140                                        if (!ta3.compatibleWith(SignatureKind.NON_GENERIC))
141                                            continue;
142                                        pool.execute(
143                                                new GenericOverrideTest(sig1,
144                                                rt1, ta1, sig2, rt2,
145                                                ta2, rt3, ta3));
146                                    }
147                                }
148                            }
149                        }
150                    }
151                }
152            }
153        }
154
155        checkAfterExec();
156    }
157
158    SignatureKind sig1, sig2;
159    ReturnTypeKind rt1, rt2, rt3;
160    TypeArgumentKind ta1, ta2, ta3;
161    JavaSource source;
162    DiagnosticChecker diagChecker;
163
164    GenericOverrideTest(SignatureKind sig1, ReturnTypeKind rt1, TypeArgumentKind ta1,
165            SignatureKind sig2, ReturnTypeKind rt2, TypeArgumentKind ta2,
166            ReturnTypeKind rt3, TypeArgumentKind ta3) {
167        this.sig1 = sig1;
168        this.sig2 = sig2;
169        this.rt1 = rt1;
170        this.rt2 = rt2;
171        this.rt3 = rt3;
172        this.ta1 = ta1;
173        this.ta2 = ta2;
174        this.ta3 = ta3;
175        this.source = new JavaSource();
176        this.diagChecker = new DiagnosticChecker();
177    }
178
179    class JavaSource extends SimpleJavaFileObject {
180
181        String template = "import java.util.*;\n" +
182                          "interface A { #S1 #R1#TA1 m(); }\n" +
183                          "interface B { #S2 #R2#TA2 m(); }\n" +
184                          "interface AB extends A, B {}\n" +
185                          "class Test {\n" +
186                          "  void test(AB ab) { #R3#TA3 n = ab.m(); }\n" +
187                          "}";
188
189        String source;
190
191        public JavaSource() {
192            super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
193            source = template.replace("#S1", sig1.paramStr).
194                    replace("#S2", sig2.paramStr).
195                    replace("#R1", rt1.retStr).
196                    replace("#R2", rt2.retStr).
197                    replace("#R3", rt3.retStr).
198                    replace("#TA1", ta1.typeargStr).
199                    replace("#TA2", ta2.typeargStr).
200                    replace("#TA3", ta3.typeargStr);
201        }
202
203        @Override
204        public CharSequence getCharContent(boolean ignoreEncodingErrors) {
205            return source;
206        }
207    }
208
209    @Override
210    public void run() {
211        JavacTask ct = (JavacTask)comp.getTask(null, fm.get(), diagChecker,
212                null, null, Arrays.asList(source));
213        try {
214            ct.analyze();
215        } catch (Throwable ex) {
216            throw new AssertionError("Error thrown when compiling the following code:\n" +
217                    source.getCharContent(true));
218        }
219        check();
220    }
221
222    void check() {
223        checkCount.incrementAndGet();
224
225        boolean errorExpected = false;
226        int mostSpecific = 0;
227
228        //first check that either |R1| <: |R2| or |R2| <: |R1|
229        if (rt1 != rt2) {
230            if (!rt1.moreSpecificThan(rt2) &&
231                    !rt2.moreSpecificThan(rt1)) {
232                errorExpected = true;
233            } else {
234                mostSpecific = rt1.moreSpecificThan(rt2) ? 1 : 2;
235            }
236        }
237
238        //check that either TA1 <= TA2 or TA2 <= TA1 (unless most specific return found above is raw)
239        if (!errorExpected) {
240            if (ta1 != ta2) {
241                boolean useStrictCheck = ta1.moreSpecificThan(ta2, true) ||
242                        ta2.moreSpecificThan(ta1, true);
243                if (!ta1.moreSpecificThan(ta2, useStrictCheck) &&
244                        !ta2.moreSpecificThan(ta1, useStrictCheck)) {
245                    errorExpected = true;
246                } else {
247                    int mostSpecific2 = ta1.moreSpecificThan(ta2, useStrictCheck) ? 1 : 2;
248                    if (mostSpecific != 0 && mostSpecific2 != mostSpecific) {
249                        errorExpected = mostSpecific == 1 ?
250                                ta1 != TypeArgumentKind.NONE :
251                                ta2 != TypeArgumentKind.NONE;
252                    } else {
253                        mostSpecific = mostSpecific2;
254                    }
255                }
256            } else if (mostSpecific == 0) {
257                //when no signature is better than the other, an arbitrary choice
258                //must be made - javac always picks the second signature
259                mostSpecific = 2;
260            }
261        }
262
263        //finally, check that most specific return type is compatible with expected type
264        if (!errorExpected) {
265            ReturnTypeKind msrt = mostSpecific == 1 ? rt1 : rt2;
266            TypeArgumentKind msta = mostSpecific == 1 ? ta1 : ta2;
267            SignatureKind mssig = mostSpecific == 1 ? sig1 : sig2;
268
269            if (!msrt.moreSpecificThan(rt3) ||
270                    !msta.assignableTo(ta3, mssig)) {
271                errorExpected = true;
272            }
273        }
274
275        if (errorExpected != diagChecker.errorFound) {
276            throw new Error("invalid diagnostics for source:\n" +
277                source.getCharContent(true) +
278                "\nFound error: " + diagChecker.errorFound +
279                "\nExpected error: " + errorExpected);
280        }
281    }
282
283    static class DiagnosticChecker
284        implements javax.tools.DiagnosticListener<JavaFileObject> {
285
286        boolean errorFound;
287
288        public void report(Diagnostic<? extends JavaFileObject> diagnostic) {
289            if (diagnostic.getKind() == Diagnostic.Kind.ERROR) {
290                errorFound = true;
291            }
292        }
293    }
294
295}
296