Package de.esoco.coroutine.step

Class Condition<I,​O>

  • All Implemented Interfaces:
    de.esoco.lib.property.Fluent<CoroutineStep<I,​O>>, org.obrel.core.FluentRelatable<CoroutineStep<I,​O>>, org.obrel.core.Relatable
    public class Condition<I,​O>
extends CoroutineStep<I,​O>
    A Coroutine step that test a logical expression in the form of a Predicate or BiPredicate and executes certain steps (which may be a subroutines) based on the boolean result.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static <I,​O>
      Condition<I,​O>      		 doIf​(java.util.function.BiPredicate<? super I,​Continuation<?>> fCondition, CoroutineStep<I,​O> rRunIfTrue)
      Tests a logical condition and executes a certain step if the condition is TRUE.
      static <I,​O>
      Condition<I,​O>      		 doIf​(java.util.function.Predicate<? super I> fCondition, CoroutineStep<I,​O> rRunIfTrue)
      Tests a logical condition and executes a certain step if the condition is TRUE.
      static <I,​O>
      Condition<I,​O>      		 doIfElse​(java.util.function.BiPredicate<? super I,​Continuation<?>> fCondition, CoroutineStep<I,​O> rRunIfTrue, CoroutineStep<I,​O> rRunIfFalse)
      Tests a logical condition and executes certain steps if the condition is either TRUE or FALSE.
      static <I,​O>
      Condition<I,​O>      		 doIfElse​(java.util.function.Predicate<? super I> fCondition, CoroutineStep<I,​O> rRunIfTrue, CoroutineStep<I,​O> rRunIfFalse)
      Tests a logical condition and executes certain steps if the condition is either TRUE or FALSE.
      protected O execute​(I input, Continuation<?> continuation)
      This method must be implemented by subclasses to provide the actual functionality of this step.
      Condition<I,​O> orElse​(CoroutineStep<I,​O> rRunIfFalse)
      Returns a new instance with the condition and TRUE step of this and a certain step to execute if the condition is FALSE.
      void runAsync​(java.util.concurrent.CompletableFuture<I> previousExecution, CoroutineStep<O,​?> nextStep, Continuation<?> continuation)
      Runs this execution step asynchronously as a continuation of a previous code execution in a CompletableFuture and proceeds to the next step afterwards.

      • Methods inherited from class org.obrel.core.RelatedObject

        deleteRelation, get, getRelation, getRelations, notifyRelationListeners, readRelations, relationsEqual, relationsHashCode, relationsString, set, set, transform, writeRelations

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface de.esoco.lib.property.Fluent

        _with

      • Methods inherited from interface org.obrel.core.FluentRelatable

        with, with, with

      • Methods inherited from interface org.obrel.core.Relatable

        deleteRelation, deleteRelation, deleteRelations, get, getAll, getOption, getRelation, getRelationCount, getRelations, getRelations, hasFlag, hasRelation, hasRelations, init, set, set, set, set, set, setOption, streamRelations, transform

    • Constructor Detail

      • Condition

        public Condition​(java.util.function.BiPredicate<? super I,​Continuation<?>> pCondition,
                 CoroutineStep<I,​O> rRunIfTrue,
                 CoroutineStep<I,​O> rRunIfFalse)
        Creates a new instance.
        Parameters:
        pCondition - The condition to test
        rRunIfTrue - The step to run if the condition is TRUE
        rRunIfFalse - The step to run if the condition is FALSE

    • Method Detail

      • doIf

        public static <I,​O> Condition<I,​O> doIf​(java.util.function.Predicate<? super I> fCondition,
                                                    CoroutineStep<I,​O> rRunIfTrue)
        Tests a logical condition and executes a certain step if the condition is TRUE. To create a condition that also runs a step if the condition is FALSE either a subsequent call to orElse(CoroutineStep) or the alternative method doIfElse(Predicate, CoroutineStep, CoroutineStep)can be used. If no 'else' step is set the coroutine will terminate if the condition is not met.

        This variant expects a unary predicate that only receives the input value. If the Continuation needs to be tested too the method doIf(BiPredicate, CoroutineStep) can be used instead.

        Parameters:
        fCondition - The condition to test
        rRunIfTrue - The step to run if the condition is TRUE
        Returns:
        The new conditional step

      • doIf

        public static <I,​O> Condition<I,​O> doIf​(java.util.function.BiPredicate<? super I,​Continuation<?>> fCondition,
                                                    CoroutineStep<I,​O> rRunIfTrue)
        Tests a logical condition and executes a certain step if the condition is TRUE. To create a condition that also runs a step if the condition is FALSE either a subsequent call to orElse(CoroutineStep) or the alternative method doIfElse(Predicate, CoroutineStep, CoroutineStep)can be used. If no 'else' step is set the coroutine will terminate if the condition is not met.

        This variant expects a binary predicate that also receives the current Continuation. If a test of the input value is sufficient the method doIf(Predicate, CoroutineStep) can be used instead.

        Parameters:
        fCondition - The condition to test
        rRunIfTrue - The step to run if the condition is TRUE
        Returns:
        The new conditional step

      • doIfElse

        public static <I,​O> Condition<I,​O> doIfElse​(java.util.function.BiPredicate<? super I,​Continuation<?>> fCondition,
                                                        CoroutineStep<I,​O> rRunIfTrue,
                                                        CoroutineStep<I,​O> rRunIfFalse)
        Tests a logical condition and executes certain steps if the condition is either TRUE or FALSE. A semantic alternative is the factory method doIf(BiPredicate, CoroutineStep) in conjunction with the instance method orElse(CoroutineStep).

        This variant expects a binary predicate that also receives the current Continuation. If a test of the input value is sufficient the method doIfElse(Predicate, CoroutineStep, CoroutineStep) can be used instead.

        Parameters:
        fCondition - The condition to test
        rRunIfTrue - The step to run if the condition is TRUE
        rRunIfFalse - The step to run if the condition is FALSE
        Returns:
        The new conditional step

      • doIfElse

        public static <I,​O> Condition<I,​O> doIfElse​(java.util.function.Predicate<? super I> fCondition,
                                                        CoroutineStep<I,​O> rRunIfTrue,
                                                        CoroutineStep<I,​O> rRunIfFalse)
        Tests a logical condition and executes certain steps if the condition is either TRUE or FALSE. A semantic alternative is the factory method doIf(BiPredicate, CoroutineStep) in conjunction with the instance method orElse(CoroutineStep).

        This variant expects a unary predicate that only receives the input value. If the Continuation needs to be tested too the method doIf(BiPredicate, CoroutineStep) can be used instead.

        Parameters:
        fCondition - The condition to test
        rRunIfTrue - The step to run if the condition is TRUE
        rRunIfFalse - The step to run if the condition is FALSE
        Returns:
        The new conditional step

      • orElse

        public Condition<I,​O> orElse​(CoroutineStep<I,​O> rRunIfFalse)
        Returns a new instance with the condition and TRUE step of this and a certain step to execute if the condition is FALSE. This is just a semantic alternative to doIfElse(BiPredicate, CoroutineStep, CoroutineStep).
        Parameters:
        rRunIfFalse - The step to run if the condition is FALSE
        Returns:
        A new conditional step

      • runAsync

        public void runAsync​(java.util.concurrent.CompletableFuture<I> previousExecution,
                     CoroutineStep<O,​?> nextStep,
                     Continuation<?> continuation)
        Runs this execution step asynchronously as a continuation of a previous code execution in a CompletableFuture and proceeds to the next step afterwards.

        Subclasses that need to suspend the invocation of the next step until some condition is met (e.g. sending or receiving data has finished) need to override this method and create a Suspension by invoking Continuation.suspend(CoroutineStep, CoroutineStep) on the next step. If the condition that caused the suspension resolves the coroutine execution can be resumed by calling Suspension.resume(Object).

        Subclasses that override this method also need to handle errors by terminating any further execution (i.e. not resuming a suspension if such exists) and forwarding the causing exception to Continuation.fail(Throwable).

        Overrides:
        runAsync in class CoroutineStep<I,​O>
        Parameters:
        previousExecution - The future of the previous code execution
        nextStep - The next step to execute or NULL for none
        continuation - The continuation of the execution

      • execute

        protected O execute​(I input,
                    Continuation<?> continuation)
        This method must be implemented by subclasses to provide the actual functionality of this step.
        Specified by:
        execute in class CoroutineStep<I,​O>
        Parameters:
        input - The input value
        continuation - The continuation of the execution
        Returns:
        The result of the execution