Package uk.ac.starlink.ttools.plottask

Class TablePointSequence

  • All Implemented Interfaces:
    PointSequence
    public abstract class TablePointSequence
extends java.lang.Object
implements PointSequence
    PointSequence abstract superclass implementation for getting sequential plot data from a table.
    Since:
    13 Aug 2008
    Author:
    Mark Taylor

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void close()
      Call when this sequence is no longer required.
      protected java.lang.Object evaluate​(gnu.jel.CompiledExpression compex)
      Convenience method which evaluates an Object-valued compiled expression.
      protected double evaluateDouble​(gnu.jel.CompiledExpression compex)
      Convenience method which evaluates a numeric-valued compiled expression.
      java.lang.String getLabel()
      Returns any text label associated with the current point.
      boolean isIncluded​(int iset)
      Indicates whether the current row is included in the given subset.
      boolean next()
      Attempts to advance the current row to the next one.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • TablePointSequence

        protected TablePointSequence​(SequentialJELRowReader rseq,
                             java.lang.String labelExpr,
                             java.lang.String[] setExprs)
                      throws gnu.jel.CompilationException
        Constructor.
        Parameters:
        rseq - row sequence representing the table which contains the actual data
        labelExpr - JEL expression for text labellling each point; may be null for no label; may have any type (converted to string before use)
        setExprs - nset-element array of boolean-valued JEL expressions giving per-set point inclusion status
        Throws:
        gnu.jel.CompilationException

    • Method Detail

      • next

        public boolean next()
        Description copied from interface: PointSequence
        Attempts to advance the current row to the next one. If true is returned the attempt has been successful, and if false is returned there are no more rows in this sequence. Since the initial position of this sequence is before the first row, this method must be called before calling any of the data access methods.
        Specified by:
        next in interface PointSequence
        Returns:
        true if row advance has succeeded, false for end of sequence

      • getLabel

        public java.lang.String getLabel()
        Description copied from interface: PointSequence
        Returns any text label associated with the current point.
        Specified by:
        getLabel in interface PointSequence
        Returns:
        text label, or null

      • isIncluded

        public boolean isIncluded​(int iset)
        Description copied from interface: PointSequence
        Indicates whether the current row is included in the given subset.
        Specified by:
        isIncluded in interface PointSequence
        Returns:
        true iff set iset is included

      • close

        public void close()
        Description copied from interface: PointSequence
        Call when this sequence is no longer required.
        Specified by:
        close in interface PointSequence

      • evaluate

        protected java.lang.Object evaluate​(gnu.jel.CompiledExpression compex)
        Convenience method which evaluates an Object-valued compiled expression. Any resulting exceptions are rethrown as PlotDataExceptions.
        Parameters:
        compex - compiled expression
        Returns:
        expression value

      • evaluateDouble

        protected double evaluateDouble​(gnu.jel.CompiledExpression compex)
        Convenience method which evaluates a numeric-valued compiled expression. Any resulting exceptions are rethrown as PlotDataExceptions.
        Parameters:
        compex - compiled expression
        Returns:
        expression value