# HG changeset patch # User darcy # Date 1360618661 28800 # Node ID d9a83ab628536934ba2718e269486662bf30b101 # Parent 55f55d4f5f9f8e6f9914fa4b7b849673b3a6875f 8007574: Provide isFunctionalInterface in javax.lang.model Reviewed-by: jjg diff -r 55f55d4f5f9f -r d9a83ab62853 langtools/src/share/classes/com/sun/tools/javac/model/JavacElements.java --- a/langtools/src/share/classes/com/sun/tools/javac/model/JavacElements.java Fri Feb 08 17:35:16 2013 -0800 +++ b/langtools/src/share/classes/com/sun/tools/javac/model/JavacElements.java Mon Feb 11 13:37:41 2013 -0800 @@ -760,6 +760,16 @@ return names.fromString(cs.toString()); } + @Override + public boolean isFunctionalInterface(TypeElement element) { + if (element.getKind() != ElementKind.INTERFACE) + return false; + else { + TypeSymbol tsym = cast(TypeSymbol.class, element); + return types.isFunctionalInterface(tsym); + } + } + /** * Returns the tree node and compilation unit corresponding to this * element, or null if they can't be found. diff -r 55f55d4f5f9f -r d9a83ab62853 langtools/src/share/classes/javax/lang/model/element/TypeElement.java --- a/langtools/src/share/classes/javax/lang/model/element/TypeElement.java Fri Feb 08 17:35:16 2013 -0800 +++ b/langtools/src/share/classes/javax/lang/model/element/TypeElement.java Mon Feb 11 13:37:41 2013 -0800 @@ -111,7 +111,6 @@ */ Name getQualifiedName(); - /** * Returns the simple name of this type element. * @@ -152,7 +151,6 @@ */ List getTypeParameters(); - /** * Returns the package of a top-level type and returns the * immediately lexically enclosing element for a {@linkplain diff -r 55f55d4f5f9f -r d9a83ab62853 langtools/src/share/classes/javax/lang/model/util/Elements.java --- a/langtools/src/share/classes/javax/lang/model/util/Elements.java Fri Feb 08 17:35:16 2013 -0800 +++ b/langtools/src/share/classes/javax/lang/model/util/Elements.java Mon Feb 11 13:37:41 2013 -0800 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2005, 2013, 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 @@ -249,4 +249,14 @@ * @param cs the character sequence to return as a name */ Name getName(CharSequence cs); + + /** + * Returns {@code true} if the type element is a functional interface, {@code false} otherwise. + * + * @param type the type element being examined + * @return {@code true} if the element is a functional interface, {@code false} otherwise + * @jls 9.8 Functional Interfaces + * @since 1.8 + */ + boolean isFunctionalInterface(TypeElement type); } diff -r 55f55d4f5f9f -r d9a83ab62853 langtools/test/tools/javac/processing/model/util/elements/TestIsFunctionalInterface.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/langtools/test/tools/javac/processing/model/util/elements/TestIsFunctionalInterface.java Mon Feb 11 13:37:41 2013 -0800 @@ -0,0 +1,115 @@ +/* + * Copyright (c) 2013, 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 8007574 + * @summary Test Elements.isFunctionalInterface + * @author Joseph D. Darcy + * @library /tools/javac/lib + * @build JavacTestingAbstractProcessor TestIsFunctionalInterface + * @compile -processor TestIsFunctionalInterface TestIsFunctionalInterface.java + */ + +import java.util.Set; +import javax.annotation.processing.*; +import javax.lang.model.SourceVersion; +import static javax.lang.model.SourceVersion.*; +import javax.lang.model.element.*; +import javax.lang.model.util.*; +import static javax.lang.model.util.ElementFilter.*; +import static javax.tools.Diagnostic.Kind.*; +import static javax.tools.StandardLocation.*; +import java.io.*; + +/** + * Test basic workings of Elements.isFunctionalInterface + */ +public class TestIsFunctionalInterface extends JavacTestingAbstractProcessor { + private int count = 0; + public boolean process(Set annotations, + RoundEnvironment roundEnv) { + if (!roundEnv.processingOver()) { + for(TypeElement type : typesIn(roundEnv.getElementsAnnotatedWith(ExpectedIsFunInt.class))) { + count++; + System.out.println(type); + if (elements.isFunctionalInterface(type) != + type.getAnnotation(ExpectedIsFunInt.class).value()) { + messager.printMessage(ERROR, + "Mismatch between expected and computed isFunctionalInterface", + type); + } + } + } else { + if (count <= 0) + messager.printMessage(ERROR, "No types with ExpectedIsFunInt processed."); + } + return true; + } +} + +@interface ExpectedIsFunInt { + boolean value(); +} + +// Examples below from the lambda specification documents. + +@ExpectedIsFunInt(false) // Equals is already an implicit member +interface Foo1 { boolean equals(Object obj); } + +@ExpectedIsFunInt(true) // Bar has one abstract non-Object method +interface Bar1 extends Foo1 { int compare(String o1, String o2); } + + +@ExpectedIsFunInt(true) // Comparator has one abstract non-Object method +interface LocalComparator { + boolean equals(Object obj); + int compare(T o1, T o2); +} + +@ExpectedIsFunInt(false) // Method Object.clone is not public +interface Foo2 { + int m(); + Object clone(); +} + +interface X1 { int m(Iterable arg); } +interface Y1 { int m(Iterable arg); } +@ExpectedIsFunInt(true) // Two methods, but they have the same signature +interface Z1 extends X1, Y1 {} + +interface X2 { Iterable m(Iterable arg); } +interface Y2 { Iterable m(Iterable arg); } +@ExpectedIsFunInt(true) // Y.m is a subsignature & return-type-substitutable +interface Z2 extends X2, Y2 {} + +interface Action { + T doit(); +} +@ExpectedIsFunInt(true) +interface LocalExecutor { T execute(Action a); } + +interface X5 { T execute(Action a); } +interface Y5 { S execute(Action a); } +@ExpectedIsFunInt(true) // Functional: signatures are "the same" +interface Exec5 extends X5, Y5 {}