@Override
    public Optional<Boolean> failAtEnd() {
        return returnFirstPresentOrEmpty(MavenOptions::failAtEnd);
    }

    @Override
    public Optional<Boolean> failNever() {
        return returnFirstPresentOrEmpty(MavenOptions::failNever);
    }

    @Override
    public Optional<Boolean> resume() {
        return returnFirstPresentOrEmpty(MavenOptions::resume);
    }

    @Override

            return MavenExecutionRequest.REACTOR_FAIL_FAST;
        } else if (mavenOptions.failAtEnd().isPresent()) {
            return MavenExecutionRequest.REACTOR_FAIL_AT_END;
        } else if (mavenOptions.failNever().isPresent()) {
            return MavenExecutionRequest.REACTOR_FAIL_NEVER;
        } else {
            return MavenExecutionRequest.REACTOR_FAIL_FAST;
        }
    }

            cmdAndArguments.add("--fail-fast");
        }
        if (mavenOptions.failAtEnd().orElse(false)) {
            cmdAndArguments.add("--fail-at-end");
        }
        if (mavenOptions.failNever().orElse(false)) {
            cmdAndArguments.add("--fail-never");
        }
        if (mavenOptions.resume().orElse(false)) {
            cmdAndArguments.add("--resume");
        }

     *
     * @return an {@link Optional} containing true if the build should never fail, false if it should fail normally, or empty if not specified
     */
    @Nonnull
    Optional<Boolean> failNever();

    /**
     * Indicates whether Maven should resume from the last failed project in a previous build.
     *

            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    public Optional<Boolean> failNever() {
        if (commandLine.hasOption(CLIManager.FAIL_NEVER)) {
            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    public Optional<Boolean> resume() {

                || FAIL_AT_END.equals(failureBehavior)
                || FAIL_NEVER.equals(failureBehavior)) {
            this.failureBehavior = failureBehavior;
        } else {
            throw new IllegalArgumentException("Invalid failure behavior (must be one of: '" + FAIL_FAST + "', '"
                    + FAIL_AT_END + "', '" + FAIL_NEVER + "').");
        }
    }

    public String getFailureBehavior() {

    public static final String FAIL_FAST = "ff";

    public static final String FAIL_ON_SEVERITY = "fos";

    public static final String FAIL_AT_END = "fae";

    public static final String FAIL_NEVER = "fn";

    public static final String RESUME = "r";

    public static final String RESUME_FROM = "rf";

    public static final String PROJECT_LIST = "pl";

    // ----------------------------------------------------------------------

    String REACTOR_FAIL_FAST = "FAIL_FAST";

    String REACTOR_FAIL_AT_END = "FAIL_AT_END";

    String REACTOR_FAIL_NEVER = "FAIL_NEVER";

    // ----------------------------------------------------------------------
    // Reactor Make Mode
    // ----------------------------------------------------------------------

                                  nullable: true
                                  type: boolean
                                failover:
                                  description: 'Optional: only one of distribute,
                                    failover or failoverPriority can be set.'
                                  items:
                                    properties:

        } else if (commandLine.hasOption(CLIManager.FAIL_AT_END)) {
            return MavenExecutionRequest.REACTOR_FAIL_AT_END;
        } else if (commandLine.hasOption(CLIManager.FAIL_NEVER)) {
            return MavenExecutionRequest.REACTOR_FAIL_NEVER;
        } else {
            // this is the default behavior.
            return MavenExecutionRequest.REACTOR_FAIL_FAST;
        }
    }