Migration Guide to Davisor Chart 4

Content

• Introduction
• New Features
• Changes in Chart XML
• Changes in JSP Tag Library
• Changes in Java API

This document serves as a guide when upgrading earlier versions of Davisor Chart to Davisor Chart 4. To learn more about the new features, we recommend that you see also the new Users' Guide and XML Reference.

There are significant architectural changes made for Davisor Chart 4, especially in data import. At the same time, the deprecated attributes were removed to keep the architecture clean. This means that Davisor Chart 4 is not backwards compatible. However, with the instructions in this document you should be able to do the migration easily.

The purpose of the changes was that the usage of Davisor Chart would be easier and more intuitive. Especially we have retought how to connect to data sources, because the integration into data sources is often the most time consuming part. We hope that the new data source interface will save an important amount of time for you.

Y-axis rotation direction for Real3D charts has been reversed. It is now the same as for isometric charts (see Axes in Users' Guide).

Point and Line Attributes

Data point visualizations (i.e. bars, columns, pie slices, points in scatter plot, shapes in line charts, stock chart symbols, etc.) are all now controlled by pointColor, pointPaint, pointShape, and pointStroke. In previous versions bars, columns, and pie slices took their rendering parameters from lineColor, linePaint, and lineStroke. The principle behind this change is that "point-something" defines how one data point will be visualized, when "line-something" defines the appearance of the lines adjancing data points. Those adjancing lines exist currently only in line and scatter charts and in their variations (like area chart).

In "bar", "column", and "pie" charts, change "line-paramters" to "point-parameters" as follows:

Old. Chart 3.x	New! Chart 4
lineColor	pointColor
linePaint	pointPaint
lineStroke	pointStroke

Other chart types have already been consistent with the principle described above.

Default Paints and Colors

The default color has earlier been always black and the default fill paint for data point visualizations has been null. In Chart 4 the default colors and fill paints are chart type specific. Typically the default outline color is still black, but in most cases the fill paint is a color palette named "default". In practice, this means that you do not need to give paint for bar, column, or pie chart to get suitable results. The changes in defaults are listed in the table below.

To let some area remain unfilled, use paint "null", "transparent", or some fully transparent paint like "white-0%".

Annotations

There is a new <annotation> tag to give hyperlink annotations and description texts. That possiblity has been since version 3.6, but now the old urlFromat and altFormat attributes are not available anymore. The <annotation> tag can be nested inside <plot> or <series> tags. The wanted URL is given by href attribute and description can be given using a nested <text> tag. All other attributes wanted to be appearing in the result can be given using nested <attr> tag. Macros, like "{.value}" or "{series1}", can be used in all annotation attributes.

The way annotation attributes are given in paints is also changed. Now the syntax is:

  paint: paint_definition "?" annotation
  paint_definition: as earlier, see e.g. Users' Guide
  annotation: annotation_attribute [ "&" annotation_attribute*]
  annotation_attribute: name "=" URL_encoded_value
  name: a valid XML attribute name, href and alt have well known meaning.
  URL_encoded_value: URL encoded value for the attribute. Will be decoded.

<area coords="..." href="index.html" alt="Home Page" onMouseOver="javascript:myfunc1()" />

The defaulting mechanism for annotations has been made uniform for all chart types. Now the order is the following:

1. annotation given in <series> tag
2. "url" and "alt" data channels
3. annotation given in <plot> tag
4. paint annotation

There are numerous changes in Davisor Chart Java API. For example, lots of deprecated constructors and methods have been removed. For example, methods getAddress(), getDescription(), and getTarget() of com.davisor.core.Annotated were deprecated for Chart 3.6. Now they are removed, and the getProperty(String) method need to be used instead with arguments "href", "alt", or "target" respectively.

One of the main changes is that com.davisor.graphics.chart.Chart has been changed from class to interface and most of its methods have been removed or changed. This affects for example to servlet coding:

Old. Chart 3.x	New! Chart 4
Chart chart = XMLDocHandler.createChart(); response.setContentType( chart.getAttributes().getEncoderType() ); chart.putImage( response.getOutputStream() );	Chart chart = XMLDocHandler.createChart(); response.setContentType( chart.getContentType() ); chart.putContent( response.getOutputStream() );