Class HistogramMLParser

  • All Implemented Interfaces:
    XmlHandler

    public class HistogramMLParser
    extends PlotMLParser
    This class constructs a histogram from specifications in PlotML (Plot Markup Language), which is an XML language. This class supports extends the base class to ensure that the associated plotter is an instance of Histogram. It ignores unrecognized elements in the DTD. The class contains an instance of the Microstar Ælfred XML parser and implements callback methods to interpret the parsed XML. The way to use this class is to construct it with a reference to a Plot object and then call its parse() method.
    Since:
    Ptolemy II 0.4
    Version:
    $Id$
    Author:
    Edward A. Lee
    Pt.AcceptedRating:
    Red (cxh)
    Pt.ProposedRating:
    Red (eal)
    • Constructor Detail

      • HistogramMLParser

        public HistogramMLParser​(Histogram plot)
        Construct an parser to parse commands for the specified plot object.
        Parameters:
        plot - The plot object to which to apply the commands.
    • Method Detail

      • endElement

        public void endElement​(java.lang.String elementName)
                        throws java.lang.Exception
        End an element. Override the base class to ignore non-histogram operations. Ælfred will call this method at the end of each element (including EMPTY elements).
        Specified by:
        endElement in interface XmlHandler
        Overrides:
        endElement in class PlotMLParser
        Parameters:
        elementName - The element type name.
        Throws:
        java.lang.Exception - If thrown by the base class.
        See Also:
        XmlHandler.endElement(java.lang.String)
      • startElement

        public void startElement​(java.lang.String elementName)
                          throws XmlException
        Start an element. This is called at the beginning of each XML element. By the time it is called, all of the attributes for the element will already have been reported using the attribute() method. Unrecognized elements are ignored.
        Specified by:
        startElement in interface XmlHandler
        Overrides:
        startElement in class PlotMLParser
        Parameters:
        elementName - The element type name.
        Throws:
        XmlException - If the element produces an error in constructing the model.
        See Also:
        XmlHandler.startElement(java.lang.String)
      • _addPoint

        protected void _addPoint​(boolean connected,
                                 java.lang.String element)
                          throws java.lang.Exception
        Add a point based on the current attributes. The second argument is the element name, used for error reporting.
        Overrides:
        _addPoint in class PlotMLParser
        Parameters:
        connected - Ignored.
        element - The name of the element.
        Throws:
        java.lang.Exception - if thrown whil parsing the y attribute.