throw new RuntimeException("Test exception in listener");
            }
        });

        try {
            factory.destroyObject(pooledObject);
            fail("Should propagate exception from listener");
        } catch (Exception e) {
            assertTrue(e.getMessage().contains("Test exception"));
        }
    }

    /**

    }

    @Test
    public void testContentException() {
        CurlResponse response = new CurlResponse();
        Exception exception = new IOException("Test exception");

        response.setContentException(exception);

        assertSame(exception, response.getContentException());
    }

    @Test
    public void testHeaders() {
        CurlResponse response = new CurlResponse();

/**
 * Classes and futures used in {@link FuturesGetCheckedTest} and {@link FuturesGetUncheckedTest}.
 */
@GwtCompatible
@NullUnmarked
final class FuturesGetCheckedInputs {
  static final Exception CHECKED_EXCEPTION = new Exception("mymessage");
  static final Future<String> FAILED_FUTURE_CHECKED_EXCEPTION =
      immediateFailedFuture(CHECKED_EXCEPTION);
  static final RuntimeException UNCHECKED_EXCEPTION = new RuntimeException("mymessage");

    public void testGet() throws Exception {
        final BeanMap map = new BeanMap();
        map.put("aaa", 1);
        map.put("bbb", 2);
        assertThat(map.get("aaa"), is((Object) 1));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testGet_NotContains() throws Exception {
        exception.expect(IllegalKeyOfBeanMapException.class);

{* ../../docs_src/handling_errors/tutorial002.py hl[14] *}

## Install custom exception handlers { #install-custom-exception-handlers }

You can add custom exception handlers with <a href="https://www.starlette.io/exceptions/" class="external-link" target="_blank">the same exception utilities from Starlette</a>.

Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

import org.codelibs.core.lang.ClassUtil;
import org.junit.Test;

/**
 * @author koichik
 */
public class TraverserUtilTest {

    /**
     * @throws Exception
     */
    @Test
    public void testFromClass_FileSystem() throws Exception {
        final Traverser traverser = TraversalUtil.getTraverser(DummyTest.class);
        assertThat(traverser, is(notNullValue()));

/**
 * Base class for all maven exceptions carrying {@link BuilderProblem}s.
 *
 * @since 4.0.0
 */
@Experimental
public abstract class MavenBuilderException extends MavenException {

    /**
     * The collection of problems associated with this exception.
     */
    private final ProblemCollector<BuilderProblem> problems;

    /**
     * Constructs a new exception with the specified message and cause.

        assertThat(out.getNotify(), is("closed"));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testCloseNull() throws Exception {
        CloseableUtil.close((OutputStream) null);
    }

    /**
     * @throws Exception
     */
    @Test
    public void testClose_noThrowIOException() throws Exception {
        final OutputStream out = new IOExceptionOccurOutputStream();

        return buf;
    }

    /**
     * Appends exception information to the buffer.
     *
     * @param buf the string buffer to append to
     * @param exception the exception to append
     * @return the updated buffer
     */
    protected StringBuilder appendException(final StringBuilder buf, final Exception exception) {
        try (ByteArrayOutputStream baos = new ByteArrayOutputStream();

        // Then: Remove should throw UnsupportedOperationException
        UnsupportedOperationException exception = assertThrows(UnsupportedOperationException.class, iterator::remove);
        assertEquals("remove", exception.getMessage());
    }

    @Test
    @DisplayName("Close should be idempotent")
    void testClose_Idempotent() throws Exception {
        // Given: A valid iterator setup