java - 用实际类替换泛型

Question

如果我有一个适合泛型的类，有没有办法包装这种丑陋？

所以这

public HasOne aMethod(Class<? extends Model> clazz){

    HasOne<Customer> hasOne = injector.getInstance(Key.get(new TypeLiteral<HasOne<Customer>>() {
    }));

    return hasOne;
}

会变成这样的东西。（这显然不能编译）

public HasOne aMethod(Class<? extends Model> clazz){

    HasOne<clazz> hasOne = injector.getInstance(Key.get(new TypeLiteral<HasOne<clazz>>() {
    }));

    return hasOne;
}

Answer 1

为什么不

public <T extends Model> HasOne<T> aMethod(Class<T> clazz){

    HasOne<T> hasOne = injector.getInstance(Key.get(new TypeLiteral<HasOne<T>>() {
    }));

    return hasOne;
}

Answer 2

public <T extends Model> HasOne<T> aMethod(Class<T> clazz){
    HasOne<T> hasOne = injector.getInstance(Key.get(new TypeLiteral<HasOne<T>>() {
    }));
    return hasOne;
}

HasOne<Customer> customer = aMethod(Customer.class);