Question

I’m using the interface Predicate<T> from com.google.common.base (Google Guava)

But I don’t know how to have the equals() method works…

Why do I get false when I type something like this :

    Predicate<Object> PredicateD = new Predicate<Object>(){
          @Override public boolean apply(Object number) {
                return ((number instanceof Double) && (Math.floor((Double)number) == (Double)number));
            }    
    };

    Predicate<Object> PredicateM = new Predicate<Object>(){
          @Override public boolean apply(Object number) {
                return ((number instanceof Double) && (Math.floor((Double)number) == (Double)number));
            }    
    };

    System.out.println(PredicateD.equals(PredicateM));

Thanks in advance for your Help,

Answer 1

You’re creating two different anonymous inner classes, but neither of them is overriding equals, so you’ll get the default implementation, whereby any two non-equal references are considered non-equal.

As the values of PredicateD and PredicateM are different references, equals returns false.