How to use NullPointerException method of org.assertj.core.api.throwable.ThrowableAssert_hasCause_Test class

Best Assertj code snippet using org.assertj.core.api.throwable.ThrowableAssert_hasCause_Test.NullPointerException

Source:ThrowableAssert_hasCause_Test.java

...21import org.junit.Test;22public class ThrowableAssert_hasCause_Test extends ThrowableAssertBaseTest {23  @Rule24  public ExpectedException thrown = none();25  private Throwable npe = new NullPointerException();26  @Override27  protected ThrowableAssert invoke_api_method() {28    return assertions.hasCause(npe);29  }30  @Override31  protected void verify_internal_effects() {32    verify(throwables).assertHasCause(getInfo(assertions), getActual(assertions), npe);33  }34  @Test35  public void should_fail_if_actual_and_expected_cause_have_different_types() {36    thrown.expectAssertionError("%n" +37                                "Expecting a cause with type:%n" +38                                "  <\"java.lang.NullPointerException\">%n" +39                                "but type was:%n" +40                                "  <\"java.lang.IllegalStateException\">.");41    assertThat(new IllegalArgumentException(new IllegalStateException())).hasCause(new NullPointerException());42  }43}...

NullPointerException

Using AI Code Generation

1    [javac]     assertThatNullPointerException().isThrownBy(() -> assertThatExceptionOfType(IOException.class).isThrownBy(() -> {2    [javac]   symbol:   method isThrownBy(ThrowingCallable)3    [javac] /home/runner/work/assertj-core/assertj-core/src/test/java/org/assertj/core/api/throwable/ThrowableAssert_hasCause_Test.java:46: error: method isThrownBy in class ThrowableAssert cannot be applied to given types;4    [javac]     assertThatNullPointerException().isThrownBy(() -> assertThatExceptionOfType(IOException.class).isThrownBy(() -> {5    [javac]   found: () -> {}6    [javac]     T extends Exception declared in method <T>isThrownBy(ThrowingCallable<T>)7    [javac] /home/runner/work/assertj-core/assertj-core/src/test/java/org/assertj/core/api/throwable/ThrowableAssert_hasCause_Test.java:46: error: method isThrownBy in class ThrowableAssert cannot be applied to given types;8    [javac]     assertThatNullPointerException().isThrownBy(() -> assertThatExceptionOfType(IOException.class).isThrownBy(() -> {9    [javac]   found: () -> {}10    [javac]     T extends Exception declared in method <T>isThrownBy(ThrowingCallable<T>)

NullPointerException

Using AI Code Generation

1import org.assertj.core.api.Assertions.assertThatThrownBy;2import org.junit.jupiter.api.Test;3public class ExceptionTest {4    void testException() {5        assertThatThrownBy(() -> {6            throw new NullPointerException();7        }).hasCause(new NullPointerException());8    }9}10In this article, we have seen how to use AssertJ to test exceptions. We have seen how to use the assertThatThrownBy() method to test whether the exception is thrown or not. We have also seen how to use the hasCause() method to test whether the exception thrown has the expected cause or not. If you have any queries or suggestions, please let me know in the comme

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