/*
* Copyright (c) 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 7062745
* @summary Regression: difference in overload resolution when two methods are maximally specific
*/
import com.sun.source.util.JavacTask;
import java.net.URI;
import java.util.Arrays;
import javax.tools.Diagnostic;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.ToolProvider;
public class GenericOverrideTest {
static int checkCount = 0;
enum SignatureKind {
NON_GENERIC(""),
GENERIC("<X>");
String paramStr;
private SignatureKind(String paramStr) {
this.paramStr = paramStr;
}
}
enum ReturnTypeKind {
LIST("List"),
ARRAYLIST("ArrayList");
String retStr;
private ReturnTypeKind(String retStr) {
this.retStr = retStr;
}
boolean moreSpecificThan(ReturnTypeKind that) {
switch (this) {
case LIST:
return that == this;
case ARRAYLIST:
return that == LIST || that == ARRAYLIST;
default: throw new AssertionError("Unexpected ret kind: " + this);
}
}
}
enum TypeArgumentKind {
NONE(""),
UNBOUND("<?>"),
INTEGER("<Number>"),
NUMBER("<Integer>"),
TYPEVAR("<X>");
String typeargStr;
private TypeArgumentKind(String typeargStr) {
this.typeargStr = typeargStr;
}
boolean compatibleWith(SignatureKind sig) {
switch (this) {
case TYPEVAR: return sig != SignatureKind.NON_GENERIC;
default: return true;
}
}
boolean moreSpecificThan(TypeArgumentKind that, boolean strict) {
switch (this) {
case NONE:
return that == this || !strict;
case UNBOUND:
return that == this || that == NONE;
case INTEGER:
case NUMBER:
case TYPEVAR:
return that == this || that == NONE || that == UNBOUND;
default: throw new AssertionError("Unexpected typearg kind: " + this);
}
}
boolean assignableTo(TypeArgumentKind that, SignatureKind sig) {
switch (this) {
case NONE:
//this case needs to workaround to javac's impl of 15.12.2.8 being too strict
//ideally should be just 'return true' (see 7067746)
return sig == SignatureKind.NON_GENERIC || that == NONE;
case UNBOUND:
return that == this || that == NONE;
case INTEGER:
case NUMBER:
return that == this || that == NONE || that == UNBOUND;
case TYPEVAR:
return true;
default: throw new AssertionError("Unexpected typearg kind: " + this);
}
}
}
public static void main(String... args) throws Exception {
//create default shared JavaCompiler - reused across multiple compilations
JavaCompiler comp = ToolProvider.getSystemJavaCompiler();
StandardJavaFileManager fm = comp.getStandardFileManager(null, null, null);
for (SignatureKind sig1 : SignatureKind.values()) {
for (ReturnTypeKind rt1 : ReturnTypeKind.values()) {
for (TypeArgumentKind ta1 : TypeArgumentKind.values()) {
if (!ta1.compatibleWith(sig1)) continue;
for (SignatureKind sig2 : SignatureKind.values()) {
for (ReturnTypeKind rt2 : ReturnTypeKind.values()) {
for (TypeArgumentKind ta2 : TypeArgumentKind.values()) {
if (!ta2.compatibleWith(sig2)) continue;
for (ReturnTypeKind rt3 : ReturnTypeKind.values()) {
for (TypeArgumentKind ta3 : TypeArgumentKind.values()) {
if (!ta3.compatibleWith(SignatureKind.NON_GENERIC)) continue;
new GenericOverrideTest(sig1, rt1, ta1, sig2, rt2, ta2, rt3, ta3).run(comp, fm);
}
}
}
}
}
}
}
}
System.out.println("Total check executed: " + checkCount);
}
SignatureKind sig1, sig2;
ReturnTypeKind rt1, rt2, rt3;
TypeArgumentKind ta1, ta2, ta3;
JavaSource source;
DiagnosticChecker diagChecker;
GenericOverrideTest(SignatureKind sig1, ReturnTypeKind rt1, TypeArgumentKind ta1,
SignatureKind sig2, ReturnTypeKind rt2, TypeArgumentKind ta2, ReturnTypeKind rt3, TypeArgumentKind ta3) {
this.sig1 = sig1;
this.sig2 = sig2;
this.rt1 = rt1;
this.rt2 = rt2;
this.rt3 = rt3;
this.ta1 = ta1;
this.ta2 = ta2;
this.ta3 = ta3;
this.source = new JavaSource();
this.diagChecker = new DiagnosticChecker();
}
class JavaSource extends SimpleJavaFileObject {
String template = "import java.util.*;\n" +
"interface A { #S1 #R1#TA1 m(); }\n" +
"interface B { #S2 #R2#TA2 m(); }\n" +
"interface AB extends A, B {}\n" +
"class Test {\n" +
" void test(AB ab) { #R3#TA3 n = ab.m(); }\n" +
"}";
String source;
public JavaSource() {
super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
source = template.replace("#S1", sig1.paramStr).
replace("#S2", sig2.paramStr).
replace("#R1", rt1.retStr).
replace("#R2", rt2.retStr).
replace("#R3", rt3.retStr).
replace("#TA1", ta1.typeargStr).
replace("#TA2", ta2.typeargStr).
replace("#TA3", ta3.typeargStr);
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) {
return source;
}
}
void run(JavaCompiler tool, StandardJavaFileManager fm) throws Exception {
JavacTask ct = (JavacTask)tool.getTask(null, fm, diagChecker,
null, null, Arrays.asList(source));
try {
ct.analyze();
} catch (Throwable ex) {
throw new AssertionError("Error thron when compiling the following code:\n" + source.getCharContent(true));
}
check();
}
void check() {
checkCount++;
boolean errorExpected = false;
int mostSpecific = 0;
//first check that either |R1| <: |R2| or |R2| <: |R1|
if (rt1 != rt2) {
if (!rt1.moreSpecificThan(rt2) &&
!rt2.moreSpecificThan(rt1)) {
errorExpected = true;
} else {
mostSpecific = rt1.moreSpecificThan(rt2) ? 1 : 2;
}
}
//check that either TA1 <= TA2 or TA2 <= TA1 (unless most specific return found above is raw)
if (!errorExpected) {
if (ta1 != ta2) {
boolean useStrictCheck = ta1.moreSpecificThan(ta2, true) || ta2.moreSpecificThan(ta1, true);
if (!ta1.moreSpecificThan(ta2, useStrictCheck) &&
!ta2.moreSpecificThan(ta1, useStrictCheck)) {
errorExpected = true;
} else {
int mostSpecific2 = ta1.moreSpecificThan(ta2, useStrictCheck) ? 1 : 2;
if (mostSpecific != 0 && mostSpecific2 != mostSpecific) {
errorExpected = mostSpecific == 1 ? ta1 != TypeArgumentKind.NONE : ta2 != TypeArgumentKind.NONE;
} else {
mostSpecific = mostSpecific2;
}
}
} else if (mostSpecific == 0) {
//when no signature is better than the other, an arbitrary choice
//must be made - javac always picks the second signature
mostSpecific = 2;
}
}
//finally, check that most specific return type is compatible with expected type
if (!errorExpected) {
ReturnTypeKind msrt = mostSpecific == 1 ? rt1 : rt2;
TypeArgumentKind msta = mostSpecific == 1 ? ta1 : ta2;
SignatureKind mssig = mostSpecific == 1 ? sig1 : sig2;
if (!msrt.moreSpecificThan(rt3) ||
!msta.assignableTo(ta3, mssig)) {
errorExpected = true;
}
}
if (errorExpected != diagChecker.errorFound) {
throw new Error("invalid diagnostics for source:\n" +
source.getCharContent(true) +
"\nFound error: " + diagChecker.errorFound +
"\nExpected error: " + errorExpected);
}
}
static class DiagnosticChecker implements javax.tools.DiagnosticListener<JavaFileObject> {
boolean errorFound;
public void report(Diagnostic<? extends JavaFileObject> diagnostic) {
if (diagnostic.getKind() == Diagnostic.Kind.ERROR) {
errorFound = true;
}
}
}
}