Best Assertj code snippet using org.assertj.core.api.Assertions.assertThatIOException
Source:PolygonIOTest.java  
...11import java.io.UnsupportedEncodingException;12import java.nio.charset.StandardCharsets;13import static org.assertj.core.api.Assertions.assertThat;14import static org.assertj.core.api.Assertions.assertThatCode;15import static org.assertj.core.api.Assertions.assertThatIOException;16/**17 * @author Marek Sabo18 */19public class PolygonIOTest {20    private static final String POLYGON_OK_TXT = "polygon-ok.txt";21    private static final String POLYGON_ERROR_TXT = "polygon-error.txt";22    private static final String POLYGON_OUT_TXT = "polygon-out.txt";23    private LabeledPolygon filledPolygon;24    private LabeledPolygon.Builder builder;25    @Before26    public void setUp() {27        builder = new LabeledPolygon.Builder();28        filledPolygon = new LabeledPolygon.Builder()29                .addVertex("a", new Vertex2D(-100, 0))30                .addVertex("b", new Vertex2D(0, -100))31                .addVertex("c", new Vertex2D(0, 100))32                .addVertex("d", new Vertex2D(-100, 200))33                .addVertex("e", new Vertex2D(-100, 200))34                .build();35    }36    @Test37    public void readCorrectFileDoesNotThrowException() {38        assertThatCode(() -> builder.read(new File(POLYGON_OK_TXT))).doesNotThrowAnyException();39    }40    @Test41    public void readCorrectStreamDoesNotThrowException() {42        assertThatCode(() -> builder.read(new FileInputStream(POLYGON_OK_TXT))).doesNotThrowAnyException();43    }44    @Test45    public void readInvalidFileThrowsException() {46        assertThatIOException().isThrownBy(() -> builder.read(new File(POLYGON_ERROR_TXT)));47    }48    @Test49    public void readInvalidStreamThrowsException() {50        assertThatIOException().isThrownBy(() -> builder.read(new FileInputStream(POLYGON_ERROR_TXT)));51    }52    @Test53    public void readInvalidStreamWrongCoordinate() throws UnsupportedEncodingException {54        // given55        String errorString = "1 2a XXX";56        // when57        InputStream stream = new ByteArrayInputStream(errorString.getBytes(StandardCharsets.UTF_8.name()));58        // then59        assertThatIOException().isThrownBy(() -> builder.read(stream));60    }61    @Test62    public void readInvalidStreamMissingParameter() throws UnsupportedEncodingException {63        // given64        String errorString = "1 2";65        // when66        InputStream stream = new ByteArrayInputStream(errorString.getBytes(StandardCharsets.UTF_8.name()));67        // then68        assertThatIOException().isThrownBy(() -> builder.read(stream));69    }70    @Test71    public void readInvalidStreamInvalidNumberFormat() throws UnsupportedEncodingException {72        // given73        String errorString = "1,1 2,1 name";74        // when75        InputStream stream = new ByteArrayInputStream(errorString.getBytes(StandardCharsets.UTF_8.name()));76        // then77        assertThatIOException().isThrownBy(() -> builder.read(stream));78    }79    @Test80    public void readValidStream() throws UnsupportedEncodingException {81        // given82        String errorString = "1 2 name with spaces";83        // when84        InputStream stream = new ByteArrayInputStream(errorString.getBytes(StandardCharsets.UTF_8.name()));85        // then86        assertThatCode(() -> builder.read(stream))87                .doesNotThrowAnyException();88    }89    @Test90    public void readCorrectFile() throws IOException {91        // when...assertThatIOException
Using AI Code Generation
1import static org.assertj.core.api.Assertions.assertThatIOException;2import java.io.File;3import java.io.IOException;4import org.junit.Test;5public class AssertJIOExceptionTest {6    public void whenIOExceptionThrown_thenAssertionSucceeds() {7        File file = new File("non_existent_file.txt");8        assertThatIOException().isThrownBy(() -> file.getCanonicalPath());9    }10}11at org.junit.Assert.assertEquals(Assert.java:115)12at org.junit.Assert.assertEquals(Assert.java:144)13at org.assertj.core.api.ThrowableAssert.catchThrowable(ThrowableAssert.java:62)14at org.assertj.core.api.AssertionsForClassTypes.catchThrowable(AssertionsForClassTypes.java:770)15at org.assertj.core.api.AssertionsForClassTypes.catchThrowable(AssertionsForClassTypes.java:785)16at org.assertj.core.api.Assertions.catchThrowable(Assertions.java:1121)17at org.assertj.core.api.Assertions.assertThatThrownBy(Assertions.java:1068)18at com.baeldung.assertj.AssertJIOExceptionTest.whenIOExceptionThrown_thenAssertionSucceeds(AssertJIOExceptionTest.java:13)assertThatIOException
Using AI Code Generation
1import static org.assertj.core.api.Assertions.assertThatIOException;2public class AssertJAssertions {3  public static void main(String[] args) {4    assertThatIOException().isThrownBy(() -> {5      throw new IOException("boom!");6    }).withMessage("boom!");7  }8}9import static org.assertj.core.api.Assertions.assertThatIOException;10public class AssertJAssertions {11  public static void main(String[] args) {12    assertThatIOException().isThrownBy(() -> {13      throw new IOException("boom!");14    }).withMessage("boom!");15  }16}assertThatIOException
Using AI Code Generation
1import java.io.File;2import java.io.IOException;3import java.nio.file.Files;4import java.nio.file.Path;5import java.nio.file.Paths;6import org.assertj.core.api.Assertions;7public class AssertJAssertionsTest {8	public static void main(String[] args) {9		Path path = Paths.get("C:\\Users\\user\\Desktop\\test.txt");10		File file = path.toFile();11		Assertions.assertThat(file).exists();12		try {13			Files.deleteIfExists(path);14		} catch (IOException e) {15			Assertions.assertThatIOException().isThrownBy(() -> {16				Files.deleteIfExists(path);17			}).withMessage("C:\\Users\\user\\Desktop\\test.txt (The system cannot find the file specified)");18		}19	}20}21Expected :C:\Users\user\Desktop\test.txt (The system cannot find the file specified)22Actual   :C:\Users\user\Desktop\test.txt (The process cannot access the file because it is being used by another process)23Method Description assertThat(Object actual) Creates a new instance of <code>ObjectAssert</code>. assertThat(boolean actual) Creates a new instance of <code>BooleanAssert</code>. assertThat(Boolean actual) Creates a new instance of <code>BooleanAssert</code>. assertThat(boolean[] actual) Creates a new instance of <code>BooleanArrayAssert</code>. assertThat(Boolean[] actual) Creates a new instance of <code>BooleanArrayAssert</code>. assertThat(byte actual) Creates a new instance of <code>ByteAssert</code>. assertThat(Byte actual) Creates a new instance of <code>ByteAssert</code>. assertThat(byte[] actual) Creates a new instance of <code>ByteArrayAssert</code>. assertThat(Byte[] actual) Creates a new instance of <code>ByteArrayAssert</code>. assertThat(char actual) Creates a new instance of <code>CharacterAssert</code>. assertThat(Character actual) Creates a new instance of <code>CharacterAssert</code>. assertThat(char[] actual) Creates a new instance of <code>CharArrayAssert</code>. assertThat(Character[] actual) Creates a new instance of <code>CharArrayAssert</code>. assertThat(double actual) Creates a new instance of <codeassertThatIOException
Using AI Code Generation
1import org.assertj.core.api.Assertions;2import org.junit.jupiter.api.Test;3import java.io.IOException;4import java.util.function.Supplier;5public class AssertJAssertionsTest {6    public void assertThatIOExceptionTest() {7        Supplier<String> supplier = () -> {8            throw new IOException("Test IOException");9        };10        Assertions.assertThatIOException().isThrownBy(supplier);11    }12}13Related Posts: AssertJ - assertThatThrownBy() method in Assertions class14AssertJ - assertThatIllegalArgumentException() method in Assertions class15AssertJ - assertThatNullPointerException() method in Assertions class16AssertJ - assertThatIllegalStateException() method in Assertions class17AssertJ - assertThatExceptionOfType() method in Assertions class18AssertJ - assertThatNoException() method in Assertions class19AssertJ - assertThatThrownBy() method in ThrowableAssert class20AssertJ - assertThatIllegalArgumentException() method in ThrowableAssert class21AssertJ - assertThatNullPointerException() method in ThrowableAssert class22AssertJ - assertThatIllegalStateException() method in ThrowableAssert class23AssertJ - assertThatExceptionOfType() method in ThrowableAssert class24AssertJ - assertThatNoException() method in ThrowableAssert class25AssertJ - assertThatIllegalArgumentException() method in ThrowableAssert.ThrowingCallable class26AssertJ - assertThatNullPointerException() method in ThrowableAssert.ThrowingCallable class27AssertJ - assertThatIllegalStateException() method in ThrowableAssert.ThrowingCallable class28AssertJ - assertThatExceptionOfType() method in ThrowableAssert.ThrowingCallable class29AssertJ - assertThatNoException() method in ThrowableAssert.ThrowingCallable class30AssertJ - assertThatIllegalArgumentException() method in ThrowableAssert.ThrowingCallable class31AssertJ - assertThatNullPointerException() method in ThrowableAssert.ThrowingCallable class32AssertJ - assertThatIllegalStateException() method in ThrowableAssert.ThrowingCallable class33AssertJ - assertThatExceptionOfType() method in ThrowableAssert.ThrowingCallable class34AssertJ - assertThatNoException() method in ThrowableAssert.ThrowingCallable class35AssertJ - assertThatIllegalArgumentException() method in ThrowableAssert.ThrowingCallable class36AssertJ - assertThatNullPointerException() method in ThrowableAssert.ThrowingCallable class37AssertJ - assertThatIllegalStateException() method in ThrowableAssert.ThrowingCallable class38AssertJ - assertThatExceptionOfType() method in ThrowableAssert.ThrowingCallable class39AssertJ - assertThatNoException() method in ThrowableAssert.ThLearn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.
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