Interface Predicate<T>

  • Type Parameters:
    T - The type of the predicate input.
    Functional Interface:
    This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

    @ConsumerType
    @FunctionalInterface
    public interface Predicate<T>
    A predicate that accepts a single argument and produces a boolean result.

    This is a functional interface and can be used as the assignment target for a lambda expression or method reference.

    • Method Summary

      All Methods Static Methods Instance Methods Abstract Methods Default Methods 
      Modifier and Type Method Description
      default Predicate<T> and​(Predicate<? super T> and)
      Compose this Predicate logical-AND the specified Predicate.
      static <T> java.util.function.Predicate<T> asJavaPredicate​(Predicate<T> wrapped)
      Returns a java.util.function.Predicate which wraps the specified Predicate and throws any thrown exceptions.
      static <T> java.util.function.Predicate<T> asJavaPredicateOrElse​(Predicate<T> wrapped, boolean orElse)
      Returns a java.util.function.Predicate which wraps the specified Predicate and the specified value.
      static <T> java.util.function.Predicate<T> asJavaPredicateOrElseGet​(Predicate<T> wrapped, java.util.function.BooleanSupplier orElseGet)
      Returns a java.util.function.Predicate which wraps the specified Predicate and the specified java.util.function.BooleanSupplier.
      static <T> Predicate<T> asPredicate​(java.util.function.Predicate<T> wrapped)
      Returns a Predicate which wraps the specified java.util.function.Predicate.
      default Predicate<T> negate()
      Return a Predicate which is the negation of this Predicate.
      default Predicate<T> or​(Predicate<? super T> or)
      Compose this Predicate logical-OR the specified Predicate.
      boolean test​(T t)
      Evaluates this predicate on the specified argument.
    • Method Detail

      • test

        boolean test​(T t)
              throws java.lang.Exception
        Evaluates this predicate on the specified argument.
        Parameters:
        t - The input to this predicate.
        Returns:
        true if the specified argument is accepted by this predicate; false otherwise.
        Throws:
        java.lang.Exception - An exception thrown by the method.
      • negate

        default Predicate<T> negate()
        Return a Predicate which is the negation of this Predicate.
        Returns:
        A Predicate which is the negation of this Predicate.
      • and

        default Predicate<T> and​(Predicate<? super T> and)
        Compose this Predicate logical-AND the specified Predicate.

        Short-circuiting is used, so the specified Predicate is not called if this Predicate returns false.

        Parameters:
        and - The Predicate to be called after this Predicate is called. Must not be null.
        Returns:
        A Predicate composed of this Predicate and the specified Predicate using logical-AND.
      • or

        default Predicate<T> or​(Predicate<? super T> or)
        Compose this Predicate logical-OR the specified Predicate.

        Short-circuiting is used, so the specified Predicate is not called if this Predicate returns true.

        Parameters:
        or - The Predicate to be called after this Predicate is called. Must not be null.
        Returns:
        A Predicate composed of this Predicate and the specified Predicate using logical-OR.
      • asJavaPredicate

        static <T> java.util.function.Predicate<T> asJavaPredicate​(Predicate<T> wrapped)
        Returns a java.util.function.Predicate which wraps the specified Predicate and throws any thrown exceptions.

        The returned java.util.function.Predicate will throw any exception thrown by the wrapped Predicate.

        Type Parameters:
        T - The type of the predicate input.
        Parameters:
        wrapped - The Predicate to wrap. Must not be null.
        Returns:
        A java.util.function.Predicate which wraps the specified Predicate.
      • asJavaPredicateOrElse

        static <T> java.util.function.Predicate<T> asJavaPredicateOrElse​(Predicate<T> wrapped,
                                                                         boolean orElse)
        Returns a java.util.function.Predicate which wraps the specified Predicate and the specified value.

        If the the specified Predicate throws an Exception, the the specified value is returned.

        Type Parameters:
        T - The type of the predicate input.
        Parameters:
        wrapped - The Predicate to wrap. Must not be null.
        orElse - The value to return if the specified Predicate throws an Exception.
        Returns:
        A java.util.function.Predicate which wraps the specified Predicate and the specified value.
      • asJavaPredicateOrElseGet

        static <T> java.util.function.Predicate<T> asJavaPredicateOrElseGet​(Predicate<T> wrapped,
                                                                            java.util.function.BooleanSupplier orElseGet)
        Returns a java.util.function.Predicate which wraps the specified Predicate and the specified java.util.function.BooleanSupplier.

        If the the specified Predicate throws an Exception, the value returned by the specified java.util.function.BooleanSupplier is returned.

        Type Parameters:
        T - The type of the predicate input.
        Parameters:
        wrapped - The Predicate to wrap. Must not be null.
        orElseGet - The java.util.function.BooleanSupplier to call for a return value if the specified Predicate throws an Exception.
        Returns:
        A java.util.function.Predicate which wraps the specified Predicate and the specified java.util.function.BooleanSupplier.
      • asPredicate

        static <T> Predicate<T> asPredicate​(java.util.function.Predicate<T> wrapped)
        Returns a Predicate which wraps the specified java.util.function.Predicate.
        Type Parameters:
        T - The type of the predicate input.
        Parameters:
        wrapped - The java.util.function.Predicate to wrap. Must not be null.
        Returns:
        A Predicate which wraps the specified java.util.function.Predicate.