jdk8-mips64-public/langtools: test/tools/javac/lambda/LambdaCapture02.java@c09b7234cded

8012556: Implement lambda methods on interfaces as static
8006140: Javac NPE compiling Lambda expression on initialization expression of static field in interface
Summary: Lambdas occurring in static contexts or those not needing instance information should be generated into static methods. This has long been the case for classes. However, as a work-around to the lack of support for statics on interfaces, interface lambda methods have been generated into default methods. For lambdas in interface static contexts (fields and static methods) this causes an NPE in javac because there is no 'this'. MethodHandles now support static methods on interfaces. This changeset allows lambda methods to be generated as static interface methods. An existing bug in Hotspot (8013875) is exposed in a test when the "-esa" flag is used. This test and another test that already exposed this bug have been marked with @ignore.
Reviewed-by: mcimadamore

     1 /*

     2  * Copyright (c) 2011, 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  */

    24 /*

    25  * @test

    26  * @bug 8003280

    27  * @summary Add lambda tests

    28  *  basic test for capture of non-mutable locals

    29  * @author  Brian Goetz

    30  * @author  Maurizio Cimadamore

    31  * @run main LambdaCapture02

    32  */

    34 public class LambdaCapture02 {

    36     static int assertionCount = 0;

    38     static void assertTrue(boolean cond) {

    39         assertionCount++;

    40         if (!cond)

    41             throw new AssertionError();

    42     }

    44     interface Tester {

    45         void test();

    46     }

    48     interface TU<T, U> {

    49         public T foo(U u);

    50     }

    52     public static <T, U> T exec(TU<T, U> lambda, U x) {

    53         return lambda.foo(x);

    54     }

    56     public Integer n = 5;

    58     //Simple local capture

    59     void test1() {

    60         final Integer N = 1;

    61         int res = LambdaCapture02.<Integer,Integer>exec((Integer x) -> x + N, 3);

    62         assertTrue(4 == res);

    63     }

    65     //Local capture with multiple scopes (anon class)

    66     void test2() {

    67         final Integer N = 1;

    68         new Tester() {

    69             public void test() {

    70                 final Integer M = 2;

    71                 int res = LambdaCapture02.<Integer,Integer>exec((Integer x) -> x + N + M, 3);

    72                 assertTrue(6 == res);

    73             }

    74         }.test();

    75     }

    77     //Local capture with multiple scopes (local class)

    78     void test3() {

    79         final Integer N = 1;

    80         class MyTester implements Tester {

    81             public void test() {

    82                 final Integer M = 2;

    83                 int res = LambdaCapture02.<Integer,Integer>exec((Integer x) -> x + N + M, 3);

    84                 assertTrue(6 == res);

    85             }

    86         }

    87         new MyTester().test();

    88     }

    90     //access to field from enclosing scope

    91     void test4() {

    92         final Integer N = 4;

    93         int res1 = LambdaCapture02.<Integer,Integer>exec((Integer x) -> x + n + N, 3);

    94         assertTrue(12 == res1);

    95         int res2 = LambdaCapture02.<Integer,Integer>exec((Integer x) -> x + LambdaCapture02.this.n + N, 3);

    96         assertTrue(12 == res2);

    97     }

    99     public static void main(String[] args) {

   100         LambdaCapture02 t = new LambdaCapture02();

   101         t.test1();

   102         t.test2();

   103         t.test3();

   104         t.test4();

   105         assertTrue(assertionCount == 5);

   106     }

   107 }

Mercurial > jdk8-mips64-public > langtools / file revision

test/tools/javac/lambda/LambdaCapture02.java@c09b7234cded

test/tools/javac/lambda/LambdaCapture02.java