Package org.apache.tinkerpop.gremlin.structure

Interface Property<V>

  • All Known Subinterfaces:
    VertexProperty<V>
    public interface Property<V>
    A Property denotes a key/value pair associated with an Edge. A property is much like a Java8 Optional in that a property can be not present (i.e. empty). The key of a property is always a String and the value of a property is an arbitrary Java object. Each underlying graph engine will typically have constraints on what Java objects are allowed to be used as values.
    Author:
    Marko A. Rodriguez (http://markorodriguez.com), Stephen Mallette (http://stephen.genoprime.com)

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Interface Description
      static class  Property.Exceptions
      Common exceptions to use with a property.

    • Method Detail

      • key

        String key()
        The key of the property.
        Returns:
        The property key

      • isPresent

        boolean isPresent()
        Whether the property is empty or not.
        Returns:
        True if the property exists, else false

      • ifPresent

        default void ifPresent​(Consumer<? super V> consumer)
        If the property is present, the consume the value as specified by the Consumer.
        Parameters:
        consumer - The consumer to process the existing value.

      • orElse

        default V orElse​(V otherValue)
        If the value is present, return the value, else return the provided value.
        Parameters:
        otherValue - The value to return if the property is not present
        Returns:
        A value

      • orElseGet

        default V orElseGet​(Supplier<? extends V> valueSupplier)
        If the value is present, return the value, else generate a value given the Supplier.
        Parameters:
        valueSupplier - The supplier to use to generate a value if the property is not present
        Returns:
        A value

      • orElseThrow

        default <E extends Throwable> V orElseThrow​(Supplier<? extends E> exceptionSupplier)
                                     throws E extends Throwable
        If the value is present, return the value, else throw the exception generated by the Supplier.
        Type Parameters:
        E - The exception type
        Parameters:
        exceptionSupplier - The supplier to generate an exception if the property is not present
        Returns:
        A value
        Throws:
        E - if the property is not present, the exception is thrown
        E extends Throwable

      • element

        Element element()
        Get the element that this property is associated with.
        Returns:
        The element associated with this property (i.e. Vertex, Edge, or VertexProperty).

      • remove

        void remove()
        Remove the property from the associated element.

      • empty

        static <V> Property<V> empty()
        Create an empty property that is not present.
        Type Parameters:
        V - The value class of the empty property
        Returns:
        A property that is not present