Chart Return Mechanisms

To improve the level of responsiveness as well as enhancing support for different server architectures, Chart FX provides two ways of processing and returning charts to the browser. These mechanisms are provided by 2 methods: the getHtmlTag method and the getHtmlData method.

When a user hits a page containing the getHtmlTag method; a chart file is saved to disk and an HTML tag (IMG, OBJECT) is returned so the browser can know the location of the chart file on the web server. Finally a second trip back to the server is necessary to pull the chart from the server and display it on the page as a static image or an active component. One of getHtmlTag's greatest advantages is that charts can be easily integrated into your existing JSP pages and it allows support for automatic browser detection. However, saving a file to disk can take its toll on server performance.

On the other hand, the getHtmlData method prevents the chart file from being saved to disk by bit-streaming the chart directly to the browser; this process leads to fewer round-trips between the client and the server. However, integration into the JSP page is awkward because you must point to another JSP file that returns the bit-stream to the browser. Also, no browser detection is provided using this methodology, preventing your application from making "smart" decisions based on the user's browser capabilities.

In terms of performance, you will learn that although the getHtmlData method is processor intensive it allows developers to boost performance and scalability and it permits the use of Chart FX on intricate server architectures such as web farms.