predicate.java

@FunctionalInterface
public Predicate<T> {
  
  void test(T t);
  
  // default method
  
  default Predicate<T> and(Predicate<? super T> other) {
    // more code here
  }
  
  default Predicate<T> or(Predicate<? super T> other) {
    // more code here
  }
  
  default Predicate<T> negate() {
    // more code here
  }
  
  // static
  
  static <T> Predicate<T> isEqual(Object o) {
    // more code here
  }
  
}