interface ParticleInt<O extends ParticleInt<O>>{
    O withSmt();
}

class Particle implements ParticleInt<Particle>{
    @Override
    public Particle withSmt() {
        return new Particle();
    }
}

class Particle2 implements ParticleInt<Particle2>{
    @Override
    public Particle2 withSmt() {
        return new Particle2();
    }
}

interface Executable<P extends ParticleInt<? extends ParticleInt>>{
    void setExecutableStrategy(ExecutableStrategy<P> s);
}

interface ExecutableStrategy<P extends ParticleInt<? extends ParticleInt>>{
    Stream<P> exec(List<P> l);
}

class Particle2Strat implements ExecutableStrategy<Particle2>{
    @Override
    public Stream<Particle2> exec(List<Particle2> l) {
        return l.stream().map(x -> x.withSmt());
    }
}

class ParticleStrat<P extends ParticleInt<? extends ParticleInt>> implements ExecutableStrategy<P>{
    @Override
    public Stream<P> exec(List<P> l) {
        return l.stream().map(x -> x.withSmt());
        // [44,38] incompatible types: inference variable R has incompatible bounds
        // equality constraints: P
        // [ERROR] lower bounds: capture#1 of ? extends ParticleInt
    }
}