1 /*
   2  * Copyright (c) 2016, 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 import java.util.regex.Pattern;
  25 
  26 import static java.util.Objects.requireNonNull;
  27 
  28 //
  29 // A set of testing utility functions
  30 //
  31 public final class TestKit {
  32 
  33     private TestKit() { }
  34 
  35     public static void assertNotThrows(ThrowingProcedure code) {
  36         requireNonNull(code, "code");
  37         assertNotThrows(() -> {
  38             code.run();
  39             return null;
  40         });
  41     }
  42 
  43     public static <V> V assertNotThrows(ThrowingFunction<V> code) {
  44         requireNonNull(code, "code");
  45         try {
  46             return code.run();
  47         } catch (Throwable t) {
  48             throw new RuntimeException("Expected to run normally, but threw "
  49                     + t.getClass().getCanonicalName(), t);
  50         }
  51     }
  52 
  53     public static <T extends Throwable> T assertThrows(Class<? extends T> clazz,
  54                                                        ThrowingProcedure code) {
  55         requireNonNull(clazz, "clazz");
  56         requireNonNull(code, "code");
  57         try {
  58             code.run();
  59         } catch (Throwable t) {
  60             if (clazz.isInstance(t)) {
  61                 return clazz.cast(t);
  62             }
  63             throw new RuntimeException("Expected to catch an exception of type "
  64                     + clazz.getCanonicalName() + ", but caught "
  65                     + t.getClass().getCanonicalName(), t);
  66 
  67         }
  68         throw new RuntimeException("Expected to catch an exception of type "
  69                 + clazz.getCanonicalName() + ", but caught nothing");
  70     }
  71 
  72     public interface ThrowingProcedure {
  73         void run() throws Throwable;
  74     }
  75 
  76     public interface ThrowingFunction<V> {
  77         V run() throws Throwable;
  78     }
  79 
  80     // The rationale behind asking for a regex is to not pollute variable names
  81     // space in the scope of assertion: if it's something as simple as checking
  82     // a message, we can do it inside
  83     public static <T extends Throwable> T assertThrows(Class<? extends T> clazz,
  84                                                        String messageRegex,
  85                                                        ThrowingProcedure code) {
  86         requireNonNull(messageRegex, "messagePattern");
  87         T t = assertThrows(clazz, code);
  88         String m = t.getMessage();
  89         if (m == null) {
  90             throw new RuntimeException(String.format(
  91                     "Expected exception message to match the regex '%s', " +
  92                             "but the message was null", messageRegex), t);
  93         }
  94         if (!Pattern.matches(messageRegex, m)) {
  95             throw new RuntimeException(String.format(
  96                     "Expected exception message to match the regex '%s', " +
  97                             "actual message: %s", messageRegex, m), t);
  98         }
  99         return t;
 100     }
 101 }