How to use expectMessage method of org.junit.rules.ExpectedException class

Best junit code snippet using org.junit.rules.ExpectedException.expectMessage

ExpectedException`org.junit.rules.ExpectedException`

The ExpectedException is a rule which helps scripts to verify that the script throws the specific exception or not

Code Snippets

Here are code snippets that can help you understand more how developers are using

Source:ExpectedExceptionTest.java

...120        public ExpectedException thrown = none();121        @Test122        public void throwsNullPointerExceptionWithMessage() {123            thrown.expect(NullPointerException.class);124            thrown.expectMessage(ARBITRARY_MESSAGE);125            throw new NullPointerException(ARBITRARY_MESSAGE + "something else");126        }127    }128    public static class ThrowExceptionWithWrongType {129        @Rule130        public ExpectedException thrown = none();131        @Test132        public void throwsNullPointerException() {133            thrown.expect(NullPointerException.class);134            throw new IllegalArgumentException();135        }136    }137    public static class HasWrongMessage {138        @Rule139        public ExpectedException thrown = none();140        @Test141        public void throwsNullPointerException() {142            thrown.expectMessage("expectedMessage");143            throw new IllegalArgumentException("actualMessage");144        }145    }146    public static class ThrowNoExceptionButExpectExceptionWithType {147        @Rule148        public ExpectedException thrown = none();149        @Test150        public void doesntThrowNullPointerException() {151            thrown.expect(NullPointerException.class);152        }153    }154    public static class WronglyExpectsExceptionMessage {155        @Rule156        public ExpectedException thrown = none();157        @Test158        public void doesntThrowAnything() {159            thrown.expectMessage("anything!");160        }161    }162    public static class ExpectsSubstring {163        @Rule164        public ExpectedException thrown = none();165        @Test166        public void throwsMore() {167            thrown.expectMessage("anything!");168            throw new NullPointerException(169                    "This could throw anything! (as long as it has the right substring)");170        }171    }172    public static class ExpectsSubstringNullMessage {173        @Rule174        public ExpectedException thrown = none();175        @Test176        public void throwsMore() {177            thrown.expectMessage("anything!");178            throw new NullPointerException();179        }180    }181    public static class ExpectsMessageMatcher {182        @Rule183        public ExpectedException thrown = none();184        @Test185        public void throwsMore() {186            thrown.expectMessage(startsWith(ARBITRARY_MESSAGE));187            throw new NullPointerException(ARBITRARY_MESSAGE + "!");188        }189    }190    public static class ExpectedMessageMatcherFails {191        @Rule192        public ExpectedException thrown = none();193        @Test194        public void throwsMore() {195            thrown.expectMessage(equalTo("Wrong start"));196            throw new NullPointerException("Back!");197        }198    }199    public static class ExpectsMatcher {200        @Rule201        public ExpectedException thrown = none();202        @Test203        public void throwsMore() {204            thrown.expect(any(Exception.class));205            throw new NullPointerException("Ack!");206        }207    }208    public static class ExpectsMultipleMatchers {209        @Rule210        public ExpectedException thrown = none();211        @Test212        public void throwsMore() {213            thrown.expect(IllegalArgumentException.class);214            thrown.expectMessage("Ack!");215            throw new NullPointerException("Ack!");216        }217    }218    //https://github.com/junit-team/junit4/pull/583219    public static class ExpectAssertionErrorWhichIsNotThrown {220        @Rule221        public ExpectedException thrown = none();222        @Test223        public void fails() {224            thrown.expect(AssertionError.class);225        }226    }227    public static class FailBeforeExpectingException {228        @Rule229        public ExpectedException thrown = none();230        @Test231        public void fails() {232            fail(ARBITRARY_MESSAGE);233            thrown.expect(IllegalArgumentException.class);234        }235    }236    public static class FailedAssumptionAndExpectException {237        @Rule238        public ExpectedException thrown = none();239        @Test240        public void failedAssumption() {241            assumeTrue(false);242            thrown.expect(NullPointerException.class);243        }244    }245    public static class ThrowExceptionWithMatchingCause {246        @Rule247        public ExpectedException thrown = none();248        @Test249        public void throwExceptionWithMatchingCause() {250            NullPointerException expectedCause = new NullPointerException("expected cause");251            thrown.expect(IllegalArgumentException.class);252            thrown.expectMessage("Ack!");253            thrown.expectCause(is(expectedCause));254            throw new IllegalArgumentException("Ack!", expectedCause);255        }256    }257    public static class ThrowExpectedNullCause {258        @Rule259        public ExpectedException thrown = none();260        @Test261        public void throwExpectedNullCause() {262            thrown.expect(IllegalArgumentException.class);263            thrown.expectMessage("Ack!");264            thrown.expectCause(nullValue(Throwable.class));265            throw new IllegalArgumentException("Ack!");266        }267    }268    public static class ThrowUnexpectedCause {269        @Rule270        public ExpectedException thrown = ExpectedException.none();271        @Test272        public void throwWithCause() {273            thrown.expect(IllegalArgumentException.class);274            thrown.expectMessage("Ack!");275            thrown.expectCause(is(new NullPointerException("expected cause")));276            throw new IllegalArgumentException("Ack!", new NullPointerException("an unexpected cause"));277        }278    }279    280    public static class UseNoCustomMessage {281        @Rule282        public ExpectedException thrown= ExpectedException.none();283        @Test284        public void noThrow() {285            thrown.expect(IllegalArgumentException.class);286        }287    }288    public static class UseCustomMessageWithPlaceHolder {...

Source:ServerProcessImplTest.java

...60  public void can_not_start_twice() throws Exception {61    prepareValidCommand("com.sonar.orchestrator.echo.SonarQubeEmulator");62    underTest.start();63    try {64      expectedException.expectMessage("Server is already started");65      expectedException.expect(IllegalStateException.class);66      underTest.start();67    } finally {68      underTest.stop();69    }70  }71  @Test72  public void can_stop_if_not_started() throws Exception {73    prepareValidCommand("com.sonar.orchestrator.echo.SonarQubeEmulator");74    underTest.start();75    underTest.stop();76    // following stops do not fail77    underTest.stop();78    underTest.stop();79  }80  @Test81  public void fail_if_command_can_not_be_executed() throws Exception {82    when(server.version()).thenReturn(Version.create("6.7"));83    // execute an invalid command from an invalid directory. That should fail.84    File invalidDir = temp.newFolder();85    when(server.getHome()).thenReturn(invalidDir);86    invalidDir.delete();87    when(commandLineFactory.create(server)).thenReturn(new CommandLine("command_does_not_exist"));88    expectedException.expectMessage("Can not execute command");89    underTest.start();90  }91  @Test92  public void fail_if_server_fails_to_start() throws Exception {93    prepareValidCommand("com.sonar.orchestrator.echo.Fail");94    expectedException.expect(IllegalStateException.class);95    expectedException.expectMessage("Server startup failure");96    underTest.start();97    verify(logWatcher).isStarted("starting");98    verify(logWatcher).isStarted("error");99    underTest.stop();100  }101  @Test102  public void fail_if_server_version_is_older_than_6_2() throws Exception {103    when(server.version()).thenReturn(Version.create("5.6"));104    expectedException.expect(IllegalStateException.class);105    expectedException.expectMessage("Minimum supported version of SonarQube is 6.2. Got 5.6.");106    underTest.start();107  }108  @Test109  public void fail_on_timeout_if_process_is_alive_but_not_correctly_started() throws IOException {110    prepareValidCommand("com.sonar.orchestrator.echo.Stuck");111    underTest.setStartupTimeout(1);112    // process is stuck, force kill. Let's reduce the regular stop command to113    // 1ms so that test does not wait for 5 minutes before force the kill114    underTest.setStopTimeout(1);115    expectedException.expectMessage("Server did not start in timely fashion");116    underTest.start();117    assertThat(underTest.isProcessAlive()).isFalse();118  }119  private void prepareValidCommand(String mainClass) throws IOException {120    when(server.version()).thenReturn(Version.create("6.7"));121    when(server.getHome()).thenReturn(new File("../echo/target"));122    File jar = TestModules.getFile("../echo/target", "echo-*.jar");123    when(logWatcher.isStarted("started")).thenReturn(true);124    when(commandLineFactory.create(server)).thenReturn(125      new CommandLine("java")126      .addArgument("-cp")127      .addArgument(jar.getCanonicalPath())128      .addArgument(mainClass)129    );...

Source:ExpectedException.java

...32    // This one saves a little typing :-)33    public void expect( Class<? extends Throwable> type, String substringOfMessage )34    {35        expect( type );36        expectMessage( substringOfMessage );37    }38    public void expectAssertionError( String message )39    {40        expect( AssertionError.class );41        expectMessage( message );42    }43    public void expectNullPointerException( String message )44    {45        expect( NullPointerException.class );46        expectMessage( message );47    }48    public void expect( Throwable error )49    {50        expect( error.getClass() );51        expectMessage( error.getMessage() );52    }53    public void expect( Class<? extends Throwable> type )54    {55        delegate.expect( type );56    }57    public void expectMessage( String message )58    {59        delegate.expectMessage( message );60    }61}

Source:TestRulesDemo.java

...33		customer.setCustName("Tom");34		customer.setCustAddress(new Address());35		36		thrown.expect(InvalidInitialAmountException.class);37		//thrown.expectMessage("Initial Amount Should be greater than 500.");38		//thrown.expectMessage("Not Null!");39		thrown.expectMessage("Initial Amount");40		acccountService.addAccount(customer, 100);41		42	}43	44	@Rule45	public Timeout timeout=new Timeout(100);46	@Test47	public void test_myLoop(){48		49		acccountService.myLoop();50	}5152}

Source:RepeatUntilExpectedExceptionRule.java

...13        Statement statement1 = createFromAnnotationWith(repeat, statement);14        Statement resultStatement = statement1 == null ? statement : statement1;15        return expectedException.apply(resultStatement, description);16    }17    public void expectMessage(Matcher<String> matcher) {18        expectedException.expectMessage(matcher);19    }20    public void expect(Class<? extends Throwable> type) {21        expectedException.expect(type);22    }23    public void expect(Matcher<?> matcher) {24        expectedException.expect(matcher);25    }26    public void expectMessage(String substring) {27        expectedException.expectMessage(substring);28    }29}...

expectMessage

Using AI Code Generation

1package com.javacodegeeks.junit;2import org.junit.Rule;3import org.junit.Test;4import org.junit.rules.ExpectedException;5public class ExpectedExceptionTest {6	public ExpectedException thrown = ExpectedException.none();7	public void shouldTestExceptionMessage() throws IndexOutOfBoundsException {8		final String[] strArray = new String[] { "a", "b", "c" };9		thrown.expect(IndexOutOfBoundsException.class);10		thrown.expectMessage("Index: 3, Size: 3");11		final String str = strArray[3];12	}13}14	at org.junit.Assert.assertEquals(Assert.java:115)15	at org.junit.Assert.assertEquals(Assert.java:144)16	at org.junit.rules.ExpectedException.handleException(ExpectedException.java:217)17	at org.junit.rules.ExpectedException.access$000(ExpectedException.java:63)18	at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:153)19	at org.junit.rules.RunRules.evaluate(RunRules.java:20)20	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)21	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)22	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)23	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)24	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)25	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)26	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)27	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)28	at org.junit.runners.ParentRunner.run(ParentRunner.java:309)29	at org.junit.runner.JUnitCore.run(JUnitCore.java:160)30	at org.junit.runner.JUnitCore.run(JUnitCore.java:138)31	at org.junit.runner.JUnitCore.runMain(JUnitCore.java:117)32	at org.junit.runner.JUnitCore.main(JUnitCore.java:96)

expectMessage

Using AI Code Generation

1import org.junit.Rule;2import org.junit.Test;3import org.junit.rules.ExpectedException;4public class ExpectedExceptionTest {5	public ExpectedException thrown = ExpectedException.none();6	public void throwsNothing() {7	}8	public void throwsNullPointerException() {9		thrown.expect(NullPointerException.class);10		throw new NullPointerException();11	}12	public void throwsNullPointerExceptionWithMessage() {13		thrown.expect(NullPointerException.class);14		thrown.expectMessage("Hello");15		throw new NullPointerException("Hello");16	}17}

expectMessage

Using AI Code Generation

1import org.junit.Rule;2import org.junit.Test;3import org.junit.rules.ExpectedException;4public class TestExceptionMessage {5    public ExpectedException thrown = ExpectedException.none();6    public void testExceptionMessage() throws IndexOutOfBoundsException {7        final String[] array = new String[1];8        thrown.expect(IndexOutOfBoundsException.class);9        thrown.expectMessage("Index: 1, Size: 1");10        final String element = array[1];11    }12}13    at org.junit.Assert.assertEquals(Assert.java:115)14    at org.junit.Assert.assertEquals(Assert.java:144)15    at org.junit.rules.ExpectedException.access$001(ExpectedException.java:94)16    at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:109)17    at org.junit.rules.RunRules.evaluate(RunRules.java:20)18    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)19    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)20    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)21    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)22    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)23    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)24    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)25    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)26    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)27    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)28    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:117)29    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:234)30    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:74)

expectMessage

Using AI Code Generation

1public void testGetMessage() {2    expectedException.expectMessage("Hello");3    expectedException.expectMessage("World");4    throw new IllegalArgumentException("Hello World");5}6public void testGetMessage() {7    MatcherAssert.assertThat("Hello World", CoreMatchers.containsString("Hello"));8    MatcherAssert.assertThat("Hello World", CoreMatchers.containsString("World"));9}10public void testGetMessage() {11    Exception exception = assertThrows(IllegalArgumentException.class, () -> {12        throw new IllegalArgumentException("Hello World");13    });14    assertEquals("Hello World", exception.getMessage());15}16public void testGetMessage() {17    Exception exception = assertThrows(IllegalArgumentException.class, () -> {18        throw new IllegalArgumentException("Hello World");19    });20    assertEquals("Hello World", exception.getMessage());21}22@Test(expectedExceptions = IllegalArgumentException.class, expectedExceptionsMessageRegExp = "Hello World")23public void testGetMessage() {24    throw new IllegalArgumentException("Hello World");25}26def "test getMessage"() {27    throw new IllegalArgumentException("Hello World")28    e << thrown()29}30public void testGetMessage() {31    Exception exception = assertThrows(IllegalArgumentException.class, () -> {32        throw new IllegalArgumentException("Hello World");33    });34    assertEquals("Hello World", exception.getMessage());35}

expectMessage

Using AI Code Generation

1    public void testExceptionMessage() {2        ExpectedException thrown = ExpectedException.none();3        thrown.expect(IllegalArgumentException.class);4        thrown.expectMessage("IllegalArgument");5        throw new IllegalArgumentException("IllegalArgument");6    }7    public void testExceptionMessageWithMatcher() {8        ExpectedException thrown = ExpectedException.none();9        thrown.expect(IllegalArgumentException.class);10        thrown.expectMessage(containsString("IllegalArgument"));11        throw new IllegalArgumentException("IllegalArgument");12    }13    public void testExceptionMessageWithMatcher2() {14        ExpectedException thrown = ExpectedException.none();15        thrown.expect(IllegalArgumentException.class);16        thrown.expectMessage(startsWith("Illegal"));17        throw new IllegalArgumentException("IllegalArgument");18    }19    public void testExceptionMessageWithMatcher3() {20        ExpectedException thrown = ExpectedException.none();21        thrown.expect(IllegalArgumentException.class);22        thrown.expectMessage(endsWith("Argument"));23        throw new IllegalArgumentException("IllegalArgument");24    }25    public void testExceptionMessageWithMatcher4() {26        ExpectedException thrown = ExpectedException.none();27        thrown.expect(IllegalArgumentException.class);28        thrown.expectMessage(both(containsString("Illegal")).and(containsString("Argument")));29        throw new IllegalArgumentException("IllegalArgument");

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