ProServe Chart Tags

The KavaChart tag library is usually the best set of tools for adding charts to your Java Server Pages. Chart tags look like this:

This simple tag is replaced by an "IMG" reference or an "OBJECT" reference that points to the actual image. The tag library hides rendering details, data management, load balancing, and so on, making your page source easy to work with.

1. Implement a "DataProvider" class to supply chart data.
2. Use the Chart Wizard or a text editor to create a style definition
3. Add the chart tag to your JSP.

That's it. ProServe tags and their attributes let you switch from images to SVG or Flash© or HTML tables, implement automatic load-balancing, add localization support using your existing resource bundles, make use of shared data sources, sessions, connection pools and so on.

Feel free to experiment with the tag library samples to see how these tags can work in your own application.

KavaChart ProServe and JSP Scriptlets

JSP Scriptlets are a popular way to use Java to add dynamic content to web pages. KavaChart ProServe objects can be used directly in a scriptlet to add a chart:

1. Create a ProServe object instance
2. Set some style properties
3. Add some data
4. Retrieve the chart for use in an <IMG> tag.

KavaChart ProServe In a Servlet

You can also use KavaChart ProServe objects to build your own servlets. This approach lets you build your own "black box" chart generator that will generate a chart from within any page. For this demonstration, we mapped our own "ChartServlet" class to the name "KavaChart", so we can generate a chart by just opening the URL "KavaChart", like this. By adding additional parameters to the URL, we can make a more complex chart.

While this approach offers some advantages, it also has some significant disadvantages: servlets generally have a single content-type, which means you won't be able to use KavaChart's drilldown hyperlinks and tooltips. Servlets created this way are also inherently less flexible than tag and scriptlet approaches, although that rigid approach can sometimes be advantageous. For example, if you want to add chart images to tooltip labels, the chart servlet can be a very effective tool.

If you want to combine the data management and image streaming advantages of a servlet with the flexibility and drilldown features of a scriptlet, the ProServe Chart Tag collection is probably the best approach.

KavaChart PHP

If you'd rather build your charts using PHP, these samples and documentation will guide you. Even though you'll still need access to a Java-enabled server somewhere, KavaChart PHP lets you build charts in pure PHP.

KavaChart JavaScript

Kavachart can be used together with JavaScript to build dynamic content into Web 2.0 style applications. These examples show how you can use asynchronous calls to a data source and a KavaChart servlet to update your web pages without refresh.

KavaChart Chart Wizard

We've created a Chart Wizard to assist you in adding KavaChart output to your application. You can use this tool to create styles for your charts or even complete servlets, JSPs and Applet definitions.

If you're a KavaChart licensee with a current maintenance subscription, you can access a Java WebStart version of the Wizard that lets you save and recall chart definitions, and combine your own data sources into the wizard's user interface for the most realistic chart modelling possible.

KavaChart Sampler

The samples demonstrated on these pages cover the most popular chart types and the most common usage techniques, but KavaChart ProServe includes an extensive library of chart types you can use to build your applications. Some of the more uncommon chart types include bubble charts, gantt charts, twin axis charts, and various financial charts.

Since KavaChart can produce an almost limitless variety of chart types, we've organized these samples into 4 collections:

• Basic Charts
• Time Series Charts
• Timeseries Charts
• Specialized Charts

All these charts are used the same way as other ProServe chart types, but some have specialized properties or data requirements. When deciding which chart is most appropriate for your application, please don't hesitate to contact us. In addition to our many years of experience creating data-driven graphics software, we have a staff of design professionals available to make recommendations on the best visual approaches to communicating your data.