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  */

    23 

    24 /*

    25  * @test

    26  * @bug 7020047

    27  * @summary Test null handling of try-with-resources statement

    28  */

    29 

    30 public class TwrNullTests {

    31     /*

    32      * Each try-with-resources statement generates two calls to the

    33      * close method for each resource: one for when there is a primary

    34      * exception present and the second for when a primary exception

    35      * is absent.  The null handling of both cases needs to be

    36      * checked.

    37      */

    38     public static void main(String... args) {

    39         testNormalCompletion();

    40         testNoSuppression();

    41     }

    42 

    43     /*

    44      * Verify empty try-with-resources on a null resource completes

    45      * normally; no NPE from the generated close call.

    46      */

    47     private static void testNormalCompletion() {

    48         try(AutoCloseable resource = null) {

    49             return; // Nothing to see here, move along.

    50         } catch (Exception e) {

    51             throw new AssertionError("Should not be reached", e);

    52         }

    53     }

    54 

    55     /*

    56      * Verify that a NPE on a null resource is <em>not</em> added as a

    57      * suppressed exception to an exception from try block.

    58      */

    59     private static void testNoSuppression() {

    60         try(AutoCloseable resource = null) {

    61             throw new java.io.IOException();

    62         } catch(java.io.IOException ioe) {

    63             Throwable[] suppressed = ioe.getSuppressed();

    64             if (suppressed.length != 0) {

    65                 throw new AssertionError("Non-empty suppressed exceptions",

    66                                          ioe);

    67             }

    68         } catch (Exception e) {

    69             throw new AssertionError("Should not be reached", e);

    70         }

    71     }

    72 }