Module org.refcodes.jobbus
Package org.refcodes.jobbus

Class SimpleJobBus<CTX>

java.lang.Object
org.refcodes.jobbus.SimpleJobBus<CTX>
Type Parameters:
CTX - The context type to use, can by any component, service or POJO.
All Implemented Interfaces:
org.refcodes.component.FlushHandle<String>, org.refcodes.component.HandleLookup<String,​org.refcodes.command.Undoable<CTX,​?,​?>>, org.refcodes.component.ProgressHandle<String>, org.refcodes.component.ResetHandle<String>, JobBus<CTX,​String>
public class SimpleJobBus<CTX>
extends Object
implements JobBus<CTX,​String>
The SimpleJobBus is a ready to use implementation of a composite JobBus wrapping a JobBusDirectory (actually a JobBus is sufficient) and delegating the method calls to the wrapped instances. The JobBusDirectory is considered to be the master from which multiple JobBus instances can be derived. In case none JobBusDirectory is considered to be required, use the empty constructor which creates its internal JobBusDirectory.

In case you want to extend the SimpleJobBus with setting concrete parameters for the generic types, please also overwrite the hook method

  • Constructor Summary

    Constructors
    Constructor Description
    SimpleJobBus​(CTX aContext)
    Instantiates the SimpleJobBus with the provided context and and a pre-defined String objects generating HandleGenerator.
    SimpleJobBus​(JobBus<CTX,​String> aJobBus)
    Instantiates the SimpleJobBus by using the provided JobBus to which the method calls are delegated.

  • Method Summary

    Modifier and Type Method Description
    protected JobBus<CTX,​String> createJobBus​(CTX aContext)
    Hook method pre-implemented useful when extending this class.
    String execute​(org.refcodes.command.Undoable<CTX,​?,​?> aJob)
    Executes the given job.
    <RET,​ E extends Exception>
    void    		 execute​(org.refcodes.command.Undoable<CTX,​RET,​E> aJob, BiConsumer<RET,​E> aResultConsumer)
    Executes the given job and invokes the provides BiConsumer lambda (closure) upon finished execution.
    <RET,​ E extends Exception>
    void    		 execute​(org.refcodes.command.Undoable<CTX,​RET,​E> aJob, Consumer<RET> aResultConsumer)
    Executes the given job and invokes the provided Consumer lambda (closure) upon finished execution.
    void flush​(String aHandle)
    <E extends Exception>
    E    		 getException​(String aHandle)
    Returns the exception of the job in case it terminated with an error.
    float getProgress​(String aHandle)
    <RET> RET getResult​(String aHandle)
    Returns the result of the job as the result of executing the job.
    <JOB extends org.refcodes.command.Undoable<CTX,​ RET,​ ?>,​ RET>
    RET    		 getResult​(JOB aJob)
    Executes the job and waits for the job's result or an exception.
    <JOB extends org.refcodes.command.Undoable<CTX,​ RET,​ ?>,​ RET>
    RET    		 getResult​(JOB aJob, long aTimeoutInMs)
    Executes the job and waits for the job's result or an exception or till the timeout has been reached.
    boolean hasException​(String aHandle)
    Determines whether the job identified by the given handle ended with an exception (instead of a regular result).
    boolean hasFlush​(String aHandle)
    boolean hasHandle​(String aHandle)
    boolean hasProgress​(String aHandle)
    boolean hasReset​(String aHandle)
    boolean hasResult​(String aHandle)
    Determines whether the job identified by the given handle has a regular result (instead of an exception).
    boolean isExecuted​(String aHandle)
    Determines whether the job has been executed.
    org.refcodes.command.Undoable<CTX,​?,​?> lookupHandle​(String aHandle)
    org.refcodes.command.Undoable<CTX,​?,​?> removeHandle​(String aHandle)
    void reset​(String aHandle)
    void waitForExecution​(String aHandle)
    Waits till the job identified by the given handle finished execution by regularly terminating or by throwing an exception.
    void waitForExecution​(String aHandle, long aTimeoutInMs)
    Waits till the job identified by the given handle finished execution by regularly terminating or by throwing an exception or till the timeout has been reached.

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface org.refcodes.component.FlushHandle

    flushUnchecked

  • Constructor Details

    • SimpleJobBus

      public SimpleJobBus​(JobBus<CTX,​String> aJobBus)
      Instantiates the SimpleJobBus by using the provided JobBus to which the method calls are delegated. Usually this constructor is used when you created a master JobBusDirectory from which client JobBus instances are to be derived. In case you do not require a master JobBusDirectory, please use the constructor SimpleJobBus(Object), which constructs the JobBus delegate with the the provided context.
      Parameters:
      aJobBus - The JobBus to delegate the method calls to.

    • SimpleJobBus

      public SimpleJobBus​(CTX aContext)
      Instantiates the SimpleJobBus with the provided context and and a pre-defined String objects generating HandleGenerator. It is up to you which context (service, Component, POJO) you want to provide to a job (Undoable) when being executed.
      Parameters:
      aContext - The context which is passed to the job (Undoable) instances when being executed.

  • Method Details

    • hasHandle

      public boolean hasHandle​(String aHandle)
      Specified by:
      hasHandle in interface org.refcodes.component.HandleLookup<String,​org.refcodes.command.Undoable<CTX,​?,​?>>

    • hasProgress

      public boolean hasProgress​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      hasProgress in interface org.refcodes.component.ProgressHandle<CTX>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException

    • hasReset

      public boolean hasReset​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      hasReset in interface org.refcodes.component.ResetHandle<CTX>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException

    • hasFlush

      public boolean hasFlush​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      hasFlush in interface org.refcodes.component.FlushHandle<CTX>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException

    • getProgress

      public float getProgress​(String aHandle) throws org.refcodes.component.UnsupportedHandleOperationRuntimeException, org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      getProgress in interface org.refcodes.component.ProgressHandle<CTX>
      Throws:
      org.refcodes.component.UnsupportedHandleOperationRuntimeException
      org.refcodes.component.UnknownHandleRuntimeException

    • lookupHandle

      public org.refcodes.command.Undoable<CTX,​?,​?> lookupHandle​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      lookupHandle in interface org.refcodes.component.HandleLookup<String,​org.refcodes.command.Undoable<CTX,​?,​?>>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException

    • reset

      public void reset​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.component.UnsupportedHandleOperationRuntimeException
      Specified by:
      reset in interface org.refcodes.component.ResetHandle<CTX>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException
      org.refcodes.component.UnsupportedHandleOperationRuntimeException

    • flush

      public void flush​(String aHandle) throws IOException, org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.component.UnsupportedHandleOperationRuntimeException
      Specified by:
      flush in interface org.refcodes.component.FlushHandle<CTX>
      Throws:
      IOException
      org.refcodes.component.UnknownHandleRuntimeException
      org.refcodes.component.UnsupportedHandleOperationRuntimeException

    • removeHandle

      public org.refcodes.command.Undoable<CTX,​?,​?> removeHandle​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Specified by:
      removeHandle in interface org.refcodes.component.HandleLookup<String,​org.refcodes.command.Undoable<CTX,​?,​?>>
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException

    • execute

      public String execute​(org.refcodes.command.Undoable<CTX,​?,​?> aJob)
      Executes the given job. By double dispatch the job's execute method is invoked. The Job is provided with a service-bus to be able to perform its task. This is an implementation of the command pattern.
      Specified by:
      execute in interface JobBus<CTX,​String>
      Parameters:
      aJob - The job to be executed.
      Returns:
      The handle associated with the provided job.

    • execute

      public <RET,​ E extends Exception> void execute​(org.refcodes.command.Undoable<CTX,​RET,​E> aJob, Consumer<RET> aResultConsumer)
      Executes the given job and invokes the provided Consumer lambda (closure) upon finished execution. The parameter is passed in case we have an ordinary result, an exceptual situation is "ignored" as the Consumer will not be invoked in such a case. In case you have to take action upon an exceptional situation, then use the JobBus.execute(Undoable, BiConsumer) method.
      Specified by:
      execute in interface JobBus<CTX,​String>
      Type Parameters:
      RET - the generic type
      E - the element type
      Parameters:
      aJob - The job to be executed.
      aResultConsumer - The Consumer lambda to be invoked upon finished execution.

    • execute

      public <RET,​ E extends Exception> void execute​(org.refcodes.command.Undoable<CTX,​RET,​E> aJob, BiConsumer<RET,​E> aResultConsumer)
      Executes the given job and invokes the provides BiConsumer lambda (closure) upon finished execution. The first parameter is passed in case we have an ordinary result, the second one is passed in case we have an exceptional situation. Either the one parameter or the other one is passed, never both of them at the same invocation! In case both arguments are null, then your job has returned null. Consider using the Optional to be returned by your job. Though consider that the Optional is NOT serializable which could cause problems with remote job execution! In case you do not have to take action upon an exceptional situation, then use the JobBus.execute(Undoable, Consumer) method.
      Specified by:
      execute in interface JobBus<CTX,​String>
      Type Parameters:
      RET - the generic type
      E - the element type
      Parameters:
      aJob - The job to be executed.
      aResultConsumer - The BiConsumer lambda to be invoked upon finished execution.
      See Also:
      "http://www.refcodes.org/blog/obliged_to_do_the_optional_or_is_it_optional"

    • waitForExecution

      public void waitForExecution​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Waits till the job identified by the given handle finished execution by regularly terminating or by throwing an exception. The handle my be used to determine if there was an exception or not and to retrieve the result or in case of an exception the exception object.
      Specified by:
      waitForExecution in interface JobBus<CTX,​String>
      Parameters:
      aHandle - The handle associated with the provided job.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.

    • waitForExecution

      public void waitForExecution​(String aHandle, long aTimeoutInMs) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.component.HandleTimeoutRuntimeException
      Waits till the job identified by the given handle finished execution by regularly terminating or by throwing an exception or till the timeout has been reached. In case the timeout has been reached before execution was finished, then a HandleTimeoutRuntimeException is thrown to abort the waiting loop. This is especially useful when a remote connection is used to managed a distributed JobBus infrastructure and due to connection issues, wait time would be endless. The handle my be used to determine if there was an exception or not and to retrieve the result or in case of an exception the exception object.
      Specified by:
      waitForExecution in interface JobBus<CTX,​String>
      Parameters:
      aHandle - The handle associated with the provided job.
      aTimeoutInMs - The timeout to wait at most even when execution did not finish. In case the timeout has been reached before execution was finished, then a HandleTimeoutRuntimeException is thrown to abort the waiting loop.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - Thrown in case the handle is not unknown.
      org.refcodes.component.HandleTimeoutRuntimeException - Thrown in case the timeout was reached before execution finished.

    • getResult

      public <JOB extends org.refcodes.command.Undoable<CTX,​ RET,​ ?>,​ RET> RET getResult​(JOB aJob) throws org.refcodes.command.NoResultAvailableRuntimeException
      Executes the job and waits for the job's result or an exception.
      Specified by:
      getResult in interface JobBus<CTX,​String>
      Type Parameters:
      JOB - the generic type
      RET - The return type of the Undoable's proceedings.
      Parameters:
      aJob - The job to execute
      Returns:
      The result of the job execution. In case the job does not produce a result by default ("void"), then the according exception is thrown. Make sure the job produces a result!
      Throws:
      org.refcodes.command.NoResultAvailableRuntimeException - in case a job has been executed which never delivers a result or which terminated with an exception. Use JobBus.hasException(Object) and JobBus.hasResult(Object) to clarify which state your Undoable (job) is in.

    • getResult

      public <JOB extends org.refcodes.command.Undoable<CTX,​ RET,​ ?>,​ RET> RET getResult​(JOB aJob, long aTimeoutInMs) throws org.refcodes.command.NoResultAvailableRuntimeException, org.refcodes.component.HandleTimeoutRuntimeException
      Executes the job and waits for the job's result or an exception or till the timeout has been reached. In case the timeout has been reached before execution was finished, then a HandleTimeoutRuntimeException is thrown to abort the waiting loop. This is especially useful when a remote connection is used to managed a distributed JobBus infrastructure and due to connection issues, wait time would be endless.
      Specified by:
      getResult in interface JobBus<CTX,​String>
      Type Parameters:
      JOB - the generic type
      RET - The return type of the Undoable's proceedings.
      Parameters:
      aJob - The job to execute
      aTimeoutInMs - The timeout to wait at most even when execution did not finish. In case the timeout has been reached before execution was finished, then a HandleTimeoutRuntimeException is thrown to abort the waiting loop.
      Returns:
      The result of the job execution. In case the job does not produce a result by default ("void"), then the according exception is thrown. Make sure the job produces a result!
      Throws:
      org.refcodes.command.NoResultAvailableRuntimeException - in case a job has been executed which never delivers a result or which terminated with an exception. Use JobBus.hasException(Object) and JobBus.hasResult(Object) to clarify which state your Undoable (job) is in.
      org.refcodes.component.HandleTimeoutRuntimeException - the handle timeout runtime exception

    • isExecuted

      public boolean isExecuted​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException
      Determines whether the job has been executed.
      Specified by:
      isExecuted in interface JobBus<CTX,​String>
      Parameters:
      aHandle - The handle associated to the job in question.
      Returns:
      True if the job represented by the handle has been executed.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.

    • hasResult

      public boolean hasResult​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.command.NotYetExecutedRuntimeException
      Determines whether the job identified by the given handle has a regular result (instead of an exception). There may be jobs which do not have any result, i.e. check if the job has been executed and also check if there is a result or an exception before requesting the according information.
      Specified by:
      hasResult in interface JobBus<CTX,​String>
      Parameters:
      aHandle - The handle associated to the job in question.
      Returns:
      The result of the job.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.
      org.refcodes.command.NotYetExecutedRuntimeException - in case the job has not been executed yet

    • hasException

      public boolean hasException​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.command.NotYetExecutedRuntimeException
      Determines whether the job identified by the given handle ended with an exception (instead of a regular result). Most jobs do not have any exception, i.e. check if the job has been executed and also check if there is a result or an exception before requesting the according information.
      Specified by:
      hasException in interface JobBus<CTX,​String>
      Parameters:
      aHandle - The handle associated to the job in question.
      Returns:
      The exception of the job's execution.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.
      org.refcodes.command.NotYetExecutedRuntimeException - in case the job has not been executed yet.

    • getResult

      public <RET> RET getResult​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.command.NotYetExecutedRuntimeException, org.refcodes.command.NoResultAvailableRuntimeException
      Returns the result of the job as the result of executing the job.
      Specified by:
      getResult in interface JobBus<CTX,​String>
      Type Parameters:
      RET - As of convenience, the return type of the Undoable instance's proceedings. CAUTION: As the handle does not permit insight on the Undoable (job) instance's return type, you may end up with a class cast exception in case you do not make sure that the result is of the expected type RET.
      Parameters:
      aHandle - The handle associated to the job in question.
      Returns:
      The result after executing the job.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.
      org.refcodes.command.NotYetExecutedRuntimeException - in case the job has not been executed yet.
      org.refcodes.command.NoResultAvailableRuntimeException - in case the job did not provide a result after execution.

    • getException

      public <E extends Exception> E getException​(String aHandle) throws org.refcodes.component.UnknownHandleRuntimeException, org.refcodes.command.NotYetExecutedRuntimeException, org.refcodes.command.NoExceptionAvailableRuntimeException
      Returns the exception of the job in case it terminated with an error.
      Specified by:
      getException in interface JobBus<CTX,​String>
      Type Parameters:
      E - the element type
      Parameters:
      aHandle - The handle associated to the job in question.
      Returns:
      The exception after executing the job.
      Throws:
      org.refcodes.component.UnknownHandleRuntimeException - in case the handle is not unknown.
      org.refcodes.command.NotYetExecutedRuntimeException - in case the job has not been executed yet.
      org.refcodes.command.NoExceptionAvailableRuntimeException - in case the job did not provide an exception after execution.

    • createJobBus

      protected JobBus<CTX,​String> createJobBus​(CTX aContext)
      Hook method pre-implemented useful when extending this class.
      Parameters:
      aContext - The context to be passed to the job (Undoable) instances when being executed.
      Returns:
      The ready to use JobBus.