1.2. EspressChart Components

EspressChart is composed of four main components:

Chart Designer

The Chart Designer is an interactive application that allows users to create and edit charts in a visual point and click environment. It can be run locally as a application or loaded as a JNLP(More about Applets in JNLP: Section 2.6 - Run Applets As JNLP). Most chart properties can be easily set and modified in the designer without writing code. Finished charts can be exported directly to a number of static formats for viewing or printing. Charts can also be saved as template (.tpl) files. A template stores the chart attributes (colors, size, etc), but none of the chart data. Every time a template is loaded, it will retrieve the latest data from the source, allowing charts to be updated without programming. Templates can also be applied to other charts or chart objects (API), allowing formatting information to be carried from one chart to another.

Chart Viewer

Chart Viewer is a JNLP(More about Applets in JNLP: Section 2.6 - Run Applets As JNLP) 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 to link to another chart.

Chart API

Chart API is an easy-to-use application programming interface that enables you to create, customize, and deploy charts within your application (and JNLPMore about Applets in JNLP: Section 2.6 - Run Applets As JNLP), on either the server-side or the client-side. It provides a Java package to a set of advanced two and three-dimensional charting library functions. Charts can be constructed with as little as one line of code.

EspressManager

EspressManager provides a back end to EspressChart. It provides the functions required to accessing and querying databases. When using the Chart Designer, EspressManager provides a seamless connection between the query utilities and the database. EspressManager also provides data buffering, file I/O, and user authentication. Although EspressManager is required when running the Chart Designer, charts can be deployed using the API or the Chart Viewer without using it.