Package org.yamcs.studio.script

Class PVUtil

java.lang.Object
org.yamcs.studio.script.PVUtil
Direct Known Subclasses:
PVUtil
public class PVUtil extends Object
The utility class to facilitate Javascript programming for PV operation.

  • Constructor Details

    • PVUtil

      public PVUtil()

  • Method Details

    • createPV

      public static final IPV createPV(String name, AbstractBaseEditPart widget) throws Exception
      Create a PV and start it. PVListener can be added to the PV to monitor its value change, but please note that the listener is executed in non-UI thread. If the code need be executed in UI thread, please use ScriptUtil.execInUI(Runnable, AbstractBaseEditPart). The monitor's maximum update rate is 50hz. If the PV updates faster than this rate, some updates will be discarded.
      Parameters:
      name - name of the PV.
      widget - the reference widget. The PV will stop when the widget is deactivated, so it is not needed to stop the pv in script.
      Returns:
      the PV.
      Throws:
      Exception - the exception that might happen while creating the pv.

    • getDouble

      public static final double getDouble(IPV pv)
      Try to get a double number from the PV.

      Some applications only deal with numeric data, so they want to interprete integer, enum and double values all the same.

      Parameters:
      pv - the PV.
      Returns:
      A double, or Double.NaN in case the value type does not decode into a number, or Double.NEGATIVE_INFINITY if the value's severity indicates that there happens to be no useful value.

    • checkPVValue

      public static VType checkPVValue(IPV pv)
      Check PV for value
      Parameters:
      pv - PV
      Returns:
      Value of PV
      Throws:
      NullPointerException - if value is null

    • getLong

      public static final Long getLong(IPV pv)
      Try to get a long integer number from the PV.

      Some applications only deal with numeric data, so they want to interprete integer, enum and double values all the same.

      Parameters:
      pv - the PV.
      Returns:
      A long integer.

    • getDouble

      public static final double getDouble(IPV pv, int index)
      Try to get a double-typed array element from the Value.
      Parameters:
      pv - The PV.
      index - The array index, 0 ... getSize()-1.
      Returns:
      A double, or Double.NaN in case the value type does not decode into a number, or Double.NEGATIVE_INFINITY if the value's severity indicates that there happens to be no useful value.

    • getDoubleArray

      public static final double[] getDoubleArray(IPV pv)
      Try to get a double-typed array from the pv.
      Parameters:
      pv - the pv.
      Returns:
      A double array, or an empty double array in case the value type does not decode into a number, or if the value's severity indicates that there happens to be no useful value.

    • getStringArray

      public static final String[] getStringArray(IPV pv)
      Get string array from pv.
      Parameters:
      pv - The PV.
      Returns:
      String array. For string array, it's the actual strings. For numeric arrays, the numbers are formatted as strings. For enum array, the labels are returned. For scalar PVs, an array with a single string is returned.

    • getLongArray

      public static final long[] getLongArray(IPV pv)
      Try to get an integer-typed array from the pv.
      Returns:
      A long integer array, or an empty long integer array in case the value type does not decode into a number, or if the value's severity indicates that there happens to be no useful value.

    • getSize

      public static final double getSize(IPV pv)
      Get the size of the pv's value
      Returns:
      Array length of the pv value. 1 for scalars.

    • getString

      public static final String getString(IPV pv)
      Converts the given pv's value into a string representation. For string values, returns the value. For numeric (double and long) values, returns a non-localized string representation. Double values use a point as the decimal separator. For other types of values, the value's IValue#format() method is called and its result returned.
      Returns:
      a string representation of the value.

    • getTimeString

      public static final String getTimeString(IPV pv)
      Get the timestamp string of the pv
      Returns:
      the timestamp in string.

    • getTimeString

      public static final String getTimeString(IPV pv, String formatPattern)
      Get the timestamp string of the pv
      Parameters:
      pv - the Pv
      formatPattern - format pattern in the form of DateTimeFormatter
      Returns:
      the timestamp in string.

    • getTimeInMilliseconds

      public static final double getTimeInMilliseconds(IPV pv)
      Get milliseconds since epoch, i.e. 1 January 1970 0:00 UTC.

      Note that we always return milliseconds relative to this UTC epoch, even if the original control system data source might use a different epoch (example: EPICS uses 1990), because the 1970 epoch is most compatible with existing programming environments.

      Returns:
      milliseconds since 1970.

    • getSeverity

      public static final int getSeverity(IPV pv)
      Get severity of the pv as an integer value.
      Returns:
      0:OK; -1: Invalid or Undefined; 1: Major; 2:Minor.

    • getSeverityString

      public static final String getSeverityString(IPV pv)
      Get severity of the PV as a string.
      Parameters:
      pv - the PV.
      Returns:
      The string representation of the severity.

    • getStatus

      public static final String getStatus(IPV pv)
      Get the status text that might describe the severity specific to the type of PV.

      For a Yamcs parameter this can be the value LOW or HIGH.

      Returns:
      the status string.

    • getUnits

      public static String getUnits(IPV pv)
      Try to get the units from the PV.

    • writePV

      public static final void writePV(String pvName, Object value, int timeout)
      Write a PV in a background job. It will first creates and connects to the PV. After PV is connected, it will set the PV with the value. If it fails to write, an error dialog will pop up.
      Parameters:
      pvName - name of the PV.
      value - value to write.
      timeout - maximum time to try connection.

    • writePV

      public static final void writePV(String pvName, Object value)
      Write a PV in a background job. It will first creates and connects to the PV. After PV is connected, it will set the PV with the value. If it fails to write, an error dialog will pop up. The maximum time to try connection is 10 second.
      Parameters:
      pvName - name of the PV.
      value - value to write.

    • getLabels

      public static final String[] getLabels(IPV pv)
      Get the list of Enum values
      Parameters:
      pv - the PV.
      Returns:
      the list of values into a string array