SLF4J与继承

Question

Say I have:

public abstract class Animal {
    // SLF4J
    private Logger logger = LoggerFactory.getLogger(Animal.class);

    // ...etc.

    public void setLogger(Logger logger) {
        this.logger = logger;
    }

    public Logger getLogger() {
        return this.logger;
    }
}

And:

public abstract class Dog extends Animal {
    // SLF4J
    private Logger logger = LoggerFactory.getLogger(Dog.class);

    // ...etc.

    public void setLogger(Logger logger) {
        this.logger = logger;
    }

    public Logger getLogger() {
        return this.logger;
    }
}

Then when I execute the following code:

Dog d1 = new Dog();
Animal a1 = new Dog();

1. Will d1 get a "Dog" logger or an "Animal" logger?
2. Will a1 get a "Dog" logger or an "Animal" logger?
3. Is there a better/cleaner/safer way to write this code so that Dog and Animal always get the correct logger?

Answer 1

d1 and a1 will have both types of loggers, ((Animal)d1).logger will be the Animal.class logger and d1.logger will be the Dog.class . Note you can't actually reference ((Animal)d1).logger out side of code in Animal class since Animal.logger is a private field.

The same will be true of a1 as well since its runtime type is Dog