ExceptionHandler exceptionHandler = new DefaultExceptionHandler();
        ExceptionSummary exceptionSummary = exceptionHandler.handleException(mojoEx);

        String expectedReference = "http://cwiki.apache.org/confluence/display/MAVEN/ConnectException";
        assertEquals(expectedReference, exceptionSummary.getReference());
    }

    @Test

       *   cause if this Future has failed.
       *
       * - And this future *has* failed: This method is called only from handleException (through
       *   getOrInitSeenExceptions). handleException tried to call setException and failed, so
       *   either this Future was cancelled (which we ruled out with the isCancelled check above),

/**
 * Handler for exceptions thrown by event subscribers.
 *
 * @since 16.0
 */
public interface SubscriberExceptionHandler {
  /** Handles exceptions thrown by subscribers. */
  void handleException(Throwable exception, SubscriberExceptionContext context);

/**
 * Handler for exceptions thrown by event subscribers.
 *
 * @since 16.0
 */
public interface SubscriberExceptionHandler {
  /** Handles exceptions thrown by subscribers. */
  void handleException(Throwable exception, SubscriberExceptionContext context);

 */
package org.apache.maven.exception;

/**
 * Transform an exception into useful end-user message.
 *
 * @since 3.0-alpha-3
 */
public interface ExceptionHandler {
    ExceptionSummary handleException(Throwable e);

       *
       * Fortunately, exceptions rarely contain references to expensive resources.
       */

      //
      seenExceptionsLocal = newConcurrentHashSet();
      /*
       * Other handleException() callers may see this as soon as we publish it. We need to populate
       * it with the initial failure before we do, or else they may think that the initial failure
       * has never been seen before.
       */

                throw e;
            } catch (Exception e) {
                // other exceptions (including InvokerException but sans Exit, see above): we need to inform user
                throw handleException(context, e);
            }
        } finally {
            Thread.currentThread().setContextClassLoader(oldCL);
            System.setProperties(oldProps);
        }
    }

/**
 * Transform an exception into useful end-user message.
 */
@Named
@Singleton
public class DefaultExceptionHandler implements ExceptionHandler {
    @Override
    public ExceptionSummary handleException(Throwable exception) {
        return handle("", exception);
    }

    private ExceptionSummary handle(String message, Throwable exception) {

            List<MavenProject> failedProjects = new ArrayList<>();

            for (Throwable exception : result.getExceptions()) {
                ExceptionSummary summary = handler.handleException(exception);
                logSummary(context, summary, references, "");

                if (exception instanceof LifecycleExecutionException lifecycleExecutionException) {

            List<MavenProject> failedProjects = new ArrayList<>();

            for (Throwable exception : result.getExceptions()) {
                ExceptionSummary summary = handler.handleException(exception);

                logSummary(summary, references, "", cliRequest.showErrors);

                if (exception instanceof LifecycleExecutionException lifecycleExecutionException) {