extension.getMaxFailures().convention(0);
        extension.getThreads().convention(1);
        extension.setRuleSetFiles(project.getLayout().files());
        extension.ruleSetsConvention(project.getProviders().provider(() -> ruleSetsConvention(extension)));
        conventionMappingOf(extension).map("targetJdk", () ->
            getDefaultTargetJdk(getJavaPluginExtension().getSourceCompatibility()));
        return extension;
    }

    }

    /**
     * The number of threads used by PMD.
     *
     * @since 7.5
     */
    public Property<Integer> getThreads() {
        return threads;
    }

    void ruleSetsConvention(Provider<List<String>> provider) {
        ruleSets.convention(provider);
    }