1 /*

     2  * Copyright (c) 2014, 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 8067422

    27  * @summary Check that the lambda names are not unnecessarily unstable

    28  * @library /tools/lib

    29  * @build ToolBox

    30  * @run main TestNonSerializableLambdaNameStability

    31  */

    32 

    33 import com.sun.tools.classfile.ClassFile;

    34 import com.sun.tools.classfile.Method;

    35 import java.io.ByteArrayInputStream;

    36 import java.io.InputStream;

    37 import java.util.ArrayList;

    38 import java.util.List;

    39 import javax.tools.StandardLocation;

    40 

    41 public class TestNonSerializableLambdaNameStability {

    42 

    43     public static void main(String... args) throws Exception {

    44         new TestNonSerializableLambdaNameStability().run();

    45     }

    46 

    47     String lambdaSource = "public class L%d {\n" +

    48                           "    public static class A {\n" +

    49                           "        private Runnable r = () -> { };\n" +

    50                           "    }\n" +

    51                           "    public static class B {\n" +

    52                           "        private Runnable r = () -> { };\n" +

    53                           "    }\n" +

    54                           "    private Runnable r = () -> { };\n" +

    55                           "}\n";

    56 

    57     String expectedLambdaMethodName = "lambda$new$0";

    58 

    59     void run() throws Exception {

    60         List<String> sources = new ArrayList<>();

    61 

    62         for (int i = 0; i < 3; i++) {

    63             sources.add(String.format(lambdaSource, i));

    64         }

    65 

    66         ToolBox tb = new ToolBox();

    67 

    68         try (ToolBox.MemoryFileManager fm = new ToolBox.MemoryFileManager()) {

    69             tb.new JavacTask()

    70               .sources(sources.toArray(new String[sources.size()]))

    71               .fileManager(fm)

    72               .run();

    73 

    74             for (String file : fm.files.get(StandardLocation.CLASS_OUTPUT).keySet()) {

    75                 byte[] fileBytes = fm.getFileBytes(StandardLocation.CLASS_OUTPUT, file);

    76                 try (InputStream in = new ByteArrayInputStream(fileBytes)) {

    77                     boolean foundLambdaMethod = false;

    78                     ClassFile cf = ClassFile.read(in);

    79                     StringBuilder seenMethods = new StringBuilder();

    80                     String sep = "";

    81                     for (Method m : cf.methods) {

    82                         String methodName = m.getName(cf.constant_pool);

    83                         if (expectedLambdaMethodName.equals(methodName)) {

    84                             foundLambdaMethod = true;

    85                             break;

    86                         }

    87                         seenMethods.append(sep);

    88                         seenMethods.append(methodName);

    89                         sep = ", ";

    90                     }

    91 

    92                     if (!foundLambdaMethod) {

    93                         throw new AbstractMethodError("Did not find the lambda method, " +

    94                                                       "found methods: " + seenMethods.toString());

    95                     }

    96                 }

    97             }

    98         }

    99     }

   100 }