The EspressChart toolkit is composed of four major components.
Chart Designer
Chart Designer is an interactive front-end application that provides users with tools for generating a wide variety of charts based on data from database queries, Excel spreadsheets, XML files, SOAP, text files, or Java classes. Its point and click interface allows charts to be created quickly with an almost infinite degree of flexibility.
Chart Designer is written in 100% pure Java. It can run as an applet in any Web browser with the Java plug-in. Chart Designer is also available as an application version for running in a standalone environment. Chart Designer allows you to view the chart from different viewpoints and to position the chart at any desired angle.
Chart Designer can also be completely customized to run within different application environments. A user-configurable Chart Designer can be launched using the Chart API. Users can control the menu and toolbar options, as well as the file i/o functions. In addition, the Chart Designer can be fully internationalized to support any foreign language.
A chart may be exported to a number of different binary formats for viewing or printing as a static image. A chart can also be stored in the .tpl format that saves the attributes of the chart (colors, size, etc.) but without the associated data. Each time a template, .tpl, file is loaded into a browser, the data is dynamically loaded from the data source. Hence, charts can be continuously updated without any programming. In addition, saving charts as templates enables users to produce charts with a consistent look and feel. Charts may also be stored in XML format or using another proprietary format, .pac which stores chart attributes as well as chart data, background images etc. Charts saved in either .tpl or .pac formats can be viewed through the Chart Viewer Java applet. EspressChart also allows the generated charts to be saved/exported using standard formats such as GIF, JPEG, PNG, WMF, SVG, Flash etc.
Chart Viewer
Chart Viewer is an lightweight applet that allows charts to be viewed remotely. It enables viewers to rotate, resize, zoom, and pan a chart. Viewers can click on individual data points to either recover the data associated with the data point, or link to another chart. Essentially, Chart Viewer provides full user interaction on the chart.
EspressManager
EspressManager serves as the "back-end" to the Chart Designer and Viewer applets. When running as an applet, EspressManager handles the data access and file i/o activities on the server side. In addition, EspressManager provides database connection and data buffering.
Chart API
Chart API,written in 100% pure Java, provides a sophisticated yet easy-to-use Java package to a set of advanced two and three-dimensional charting library functions. High-performance three-dimensional graphics algorithms are employed to allow visualization and manipulation of the chart (pan, zoom, xyz-scale, rotate, translate etc.) in real time. You can use as little as one line of code to plot a chart. It supports JDBC-ODBC connectivity to retrieve data from any database directly. Other data sources supported are Excel spreadsheets, XML files, SOAP, text files, or Java classes. Chart API can be used in applets as well as in servlets/JSP(JavaServer Pages) applications.
