FooStarter.java

@HandlesTypes(Foo.class)
public class FooStarter implements ServletContainerInitializer {
    @Override
    public void onStartup(final Set<Class<?>> set, final ServletContext servletContext) {
        System.out.println(set.stream().map(Class::getName).collect(joining("\n", "\nClasses:\n\n", "\n\n")));
        if (set.stream()
                .filter(it -> it.isAnnotationPresent(Foo.class))
                .count() != set.size()) {
            throw new IllegalArgumentException("Invalid scanning");
        }
    }
}

/*
with foo:
*/
@Target({TYPE, FIELD})
@Retention(RUNTIME)
public @interface Foo {
}

/** and beans */
@Foo
public class OnClass {
}

public class OnField {
    @Foo
    private String name;
}