Package org.eclipse.scanning.device.composite

Class CompositeNexusScannable<N extends NXobject>

java.lang.Object
org.eclipse.scanning.api.AbstractNameable
org.eclipse.scanning.api.AbstractNameableTimeoutable
org.eclipse.scanning.api.AbstractScannable<DeviceValueMultiPosition>
org.eclipse.scanning.device.composite.CompositeNexusScannable<N>
Type Parameters:
N - the type of nexus object created for this scannable.
T - the type of object returned by getPosition(). Not normally used by this class
All Implemented Interfaces:
INexusDevice<N>, IActivatable, IBoundable<DeviceValueMultiPosition>, ILevel, INameable, IScanAttributeContainer, IScannable<DeviceValueMultiPosition>, ITimeoutable, ITolerable<DeviceValueMultiPosition>, IPositionListenable
public class CompositeNexusScannable<N extends NXobject> extends AbstractScannable<DeviceValueMultiPosition> implements INexusDevice<N>
A scannable that returns a nexus object created by combining the nexus objects of other scannables. This scannable should only be used as a per scan monitor, attempts to use it as a per point monitor will fail.

  • Constructor Details

    • CompositeNexusScannable

      public CompositeNexusScannable()

  • Method Details

    • getPosition

      public DeviceValueMultiPosition getPosition() throws ScanningException
      Description copied from interface: IBoundable
      The position is the value which should be: 1. Greater than or equal to the lower 2. Less than or equal to the upper. 3. One of the permitted values, if they are not null.
      Specified by:
      getPosition in interface IBoundable<N extends NXobject>
      Returns:
      Throws:
      ScanningException - if the position cannot be read for any reason

    • setPosition

      public DeviceValueMultiPosition setPosition(DeviceValueMultiPosition value, IPosition position) throws ScanningException
      Description copied from interface: IScannable
      Moves to the position required, blocking until it is complete. Similar to moveTo(...) in GDA8
      Specified by:
      setPosition in interface IScannable<N extends NXobject>
      Parameters:
      value - that this scalar should take.
      position - if within in a scan or null if not within a scan.
      Returns:
      the new position attained by the device, if known. (Saves additional call to getPosition()) If not know the demand value is returned. NOTE if null is returned the system will call getPosition() again.
      Throws:
      ScanningException

    • getNexusClass

      public NexusBaseClass getNexusClass()

    • setNexusClass

      public void setNexusClass(NexusBaseClass nexusClass)

    • getNexusCategory

      public NexusBaseClass getNexusCategory()

    • setNexusCategory

      public void setNexusCategory(NexusBaseClass nexusCategory)

    • getNexusProvider

      public NexusObjectProvider<N> getNexusProvider(NexusScanInfo info) throws NexusException
      Description copied from interface: INexusDevice
      Returns the object provider required for writing correct NeXus files.

      In this method you should prepare the LazyDatasets the device will fill during the scan. You can also write out static device metadata, which will not change during the scan.

      Use the methods on NexusNodeFactory to create a NeXus object which matches the device e.g. a NXdetector. final NXdetector detector = NexusNodeFactory.createNXdetector();

      On the detector object you can create LazyDatasets and keep references which you can later use during the scan to write data. e.g. imageData = detector.initializeLazyDataset(NXdetector.NX_DATA, info.getRank() + 2, Double.class); You should also set chunking on the LazyDatasets you create e.g. imageData.setChunking(info.createChunk(detectorXSize, detectorYSize));.

      In this method you can also write static metadata such as the detector exposure e.g. detector.setField("exposure_time", model.getExposure());. Or static datasets such as the image axis data detector.setDataset("image_x_axis", DatasetFactory.createLinearSpace(DoubleDataset.class, minX, maxX, xPoints)); For fields that are defined in the NXDL base class definition for the returned nexus object, a setXXX or setXXXScalar method may be used as appropriate, e.g. detector.setLocalName(DatasetFactory.createFromObject("my detector")); or detector.setLocalNameScalar("my detector");

      If this device is a 'metadata scannable', then the device should write its data at this point directly into the returned nexus object. This can be done with the NXobject.setField(String, Object) method, or the setXXXScalar methods for fields defined in the appropriate NXDL base class definition.

      The default implementation of this method throws UnsupportedOperationException. One of either this method or INexusDevice.getNexusProviders(NexusScanInfo) must be overridden to create and return the nexus object(s) for this INexusDevice.

      Specified by:
      getNexusProvider in interface INexusDevice<N extends NXobject>
      Parameters:
      info - information about the scan which can be useful when creating datasets e.g. info.getRank()
      Returns:
      The NXobject created using the nodeFactory to represent this device
      Throws:
      NexusException - if the nexus object could not be created for any reason

    • getChildNodes

      public List<ChildNode> getChildNodes()

    • setChildNodes

      public void setChildNodes(List<ChildNode> childNodes)

    • abort

      public void abort() throws UnsupportedOperationException
      Description copied from interface: IScannable
      Call to terminate a movement before it is complete, for example when ScannablePositioner#abort is called due to an exception with another IScannable's movement
      Specified by:
      abort in interface IScannable<N extends NXobject>
      Throws:
      UnsupportedOperationException