jdk8-mips64-public/langtools: test/tools/javac/lambda/GenericMethodRefImplClass.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) 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  */

    24 /*

    25  * @test

    26  * @bug 8009582

    27  * @summary Method reference generic constructor gives: IllegalArgumentException: Invalid lambda deserialization

    28  * @author  Robert Field

    29  * @run main GenericMethodRefImplClass

    30  */

    32 import java.io.*;

    33 import java.util.*;

    35 public class GenericMethodRefImplClass {

    37     static int assertionCount = 0;

    39     static void assertTrue(boolean cond) {

    40         assertionCount++;

    41         if (!cond)

    42             throw new AssertionError();

    43     }

    45     public static void main(String[] args) throws Exception {

    46         try {

    47             // Write lambdas out

    48             ByteArrayOutputStream baos = new ByteArrayOutputStream();

    49             ObjectOutput out = new ObjectOutputStream(baos);

    51             write(out, HashMap::new );

    52             out.flush();

    53             out.close();

    55             // Read them back

    56             ByteArrayInputStream bais =

    57                 new ByteArrayInputStream(baos.toByteArray());

    58             ObjectInputStream in = new ObjectInputStream(bais);

    59             readIt(in);

    60             in.close();

    61         } catch (IOException e) {

    62             e.printStackTrace();

    63             throw e;

    64         }

    65         assertTrue(assertionCount == 1);

    66     }

    68     static void write(ObjectOutput out, GenericMethodRefImplClassLSI lamb) throws IOException {

    69         out.writeObject(lamb);

    70     }

    72     static void readIt(ObjectInputStream in)  throws IOException, ClassNotFoundException {

    73         GenericMethodRefImplClassLSI ls = (GenericMethodRefImplClassLSI) in.readObject();

    74         Map result = ls.convert();

    75         assertTrue(result.getClass().getName().equals("java.util.HashMap"));

    76     }

    77 }

    79 interface GenericMethodRefImplClassLSI extends Serializable {

    80     Map convert();

    81 }

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

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

test/tools/javac/lambda/GenericMethodRefImplClass.java