Class Predicates

java.lang.Object
org.parboiled.common.Predicates

public final class Predicates extends Object
  • Method Summary

    Modifier and Type
    Method
    Description
    static <T> Predicate<T>
    Returns a predicate that always evaluates to false.
    static <T> Predicate<T>
    Returns a predicate that always evaluates to true.
    static <T> Predicate<T>
    and(Collection<? extends Predicate<? super T>> components)
    Returns a predicate that evaluates to true if each of its components evaluates to true.
    static <T> Predicate<T>
    and(Predicate<? super T>... components)
    Returns a predicate that evaluates to true if each of its components evaluates to true.
    static <T> Predicate<T>
    and(Predicate<? super T> first, Predicate<? super T> second)
    Returns a predicate that evaluates to true if both of its components evaluate to true.
    static <T> Predicate<T>
    equalTo(T target)
    Returns a predicate that evaluates to true if the object being tested equals() the given target or both are null.
    static <T> Predicate<T>
    in(Collection<? extends T> target)
    Returns a predicate that evaluates to true if the object reference being tested is a member of the given collection.
    instanceOf(Class<?> clazz)
    Returns a predicate that evaluates to true if the object being tested is an instance of the given class.
    static <T> Predicate<T>
    Returns a predicate that evaluates to true if the object reference being tested is null.
    static <T> Predicate<T>
    not(Predicate<T> predicate)
    Returns a predicate that evaluates to true if the given predicate evaluates to false.
    static <T> Predicate<T>
    Returns a predicate that evaluates to true if the object reference being tested is not null.
    static <T> Predicate<T>
    or(Collection<? extends Predicate<? super T>> components)
    Returns a predicate that evaluates to true if any one of its components evaluates to true.
    static <T> Predicate<T>
    or(Predicate<? super T>... components)
    Returns a predicate that evaluates to true if any one of its components evaluates to true.
    static <T> Predicate<T>
    or(Predicate<? super T> first, Predicate<? super T> second)
    Returns a predicate that evaluates to true if either of its components evaluates to true.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Method Details

    • alwaysTrue

      public static <T> Predicate<T> alwaysTrue()
      Returns a predicate that always evaluates to true.
      Returns:
      a predicate
    • alwaysFalse

      public static <T> Predicate<T> alwaysFalse()
      Returns a predicate that always evaluates to false.
      Returns:
      a predicate
    • isNull

      public static <T> Predicate<T> isNull()
      Returns a predicate that evaluates to true if the object reference being tested is null.
      Returns:
      a predicate
    • notNull

      public static <T> Predicate<T> notNull()
      Returns a predicate that evaluates to true if the object reference being tested is not null.
      Returns:
      a predicate
    • not

      public static <T> Predicate<T> not(Predicate<T> predicate)
      Returns a predicate that evaluates to true if the given predicate evaluates to false.
      Parameters:
      predicate - the inner predicate
      Returns:
      a predicate
    • and

      public static <T> Predicate<T> and(Collection<? extends Predicate<? super T>> components)
      Returns a predicate that evaluates to true if each of its components evaluates to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as a false predicate is found. It defensively copies the iterable passed in, so future changes to it won't alter the behavior of this predicate. If components is empty, the returned predicate will always evaluate to true.
      Parameters:
      components - the components
      Returns:
      a predicate
    • and

      public static <T> Predicate<T> and(Predicate<? super T>... components)
      Returns a predicate that evaluates to true if each of its components evaluates to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as a false predicate is found. It defensively copies the array passed in, so future changes to it won't alter the behavior of this predicate. If components is empty, the returned predicate will always evaluate to true.
      Parameters:
      components - the components
      Returns:
      a predicate
    • and

      public static <T> Predicate<T> and(Predicate<? super T> first, Predicate<? super T> second)
      Returns a predicate that evaluates to true if both of its components evaluate to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as a false predicate is found.
      Parameters:
      first - the first
      second - the second
      Returns:
      a predicate
    • or

      public static <T> Predicate<T> or(Collection<? extends Predicate<? super T>> components)
      Returns a predicate that evaluates to true if any one of its components evaluates to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as as soon as a true predicate is found. It defensively copies the iterable passed in, so future changes to it won't alter the behavior of this predicate. If components is empty, the returned predicate will always evaluate to false.
      Parameters:
      components - the components
      Returns:
      a predicate
    • or

      public static <T> Predicate<T> or(Predicate<? super T>... components)
      Returns a predicate that evaluates to true if any one of its components evaluates to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as as soon as a true predicate is found. It defensively copies the array passed in, so future changes to it won't alter the behavior of this predicate. If components is empty, the returned predicate will always evaluate to false.
      Parameters:
      components - the components
      Returns:
      a predicate
    • or

      public static <T> Predicate<T> or(Predicate<? super T> first, Predicate<? super T> second)
      Returns a predicate that evaluates to true if either of its components evaluates to true. The components are evaluated in order, and evaluation will be "short-circuited" as soon as as soon as a true predicate is found.
      Parameters:
      first - the first
      second - the second
      Returns:
      a predicate
    • equalTo

      public static <T> Predicate<T> equalTo(T target)
      Returns a predicate that evaluates to true if the object being tested equals() the given target or both are null.
      Parameters:
      target - the target
      Returns:
      a predicate
    • instanceOf

      public static Predicate<Object> instanceOf(Class<?> clazz)
      Returns a predicate that evaluates to true if the object being tested is an instance of the given class. If the object being tested is null this predicate evaluates to false.

      Parameters:
      clazz - the clazz
      Returns:
      a predicate
    • in

      public static <T> Predicate<T> in(Collection<? extends T> target)
      Returns a predicate that evaluates to true if the object reference being tested is a member of the given collection. It does not defensively copy the collection passed in, so future changes to it will alter the behavior of the predicate.

      This method can technically accept any Collection<?>, but using a typed collection helps prevent bugs. This approach doesn't block any potential users since it is always possible to use Predicates.<Object>in().

      Parameters:
      target - the collection that may contain the function input
      Returns:
      a predicate