Download An Introduction to ECharts: The Concise User Manual

1.1
History
ECharts was originally developed at AT&T Labs–Research to support
an advanced telecommunications project which evolved into a nationwide commercial product offering [3]. Currently ECharts is used in a
number of new research projects at AT&T.
1.2
Why Use ECharts?
An ECharts machine is a specification of event-driven behavior. Application domains that will benefit from using ECharts are telecommunications, web applications, user interfaces, . . . really any application
domain where a system responds to events occurring in its environment.
ECharts isn’t meant to be a stand-alone programming language.
ECharts specifies a program’s control flow in response to events received from the environment. To specify data operations, ECharts
machines rely on host language statements embedded in the machine,
for example, Java. Furthermore, an ECharts machine only constitutes
a program unit in a larger host language program, it isn’t necessarily
a program’s locus of control.
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Developing an ECharts Machine
The ECharts SDK (System Development Kit) is split into two major
components: (1) a translator and (2) a runtime system. The translator
translates an ECharts machine into a host language program module,
for example, Java. The runtime system is a host language library
comprising the ECharts machine interpreter, that is, the code that
actually executes the machine. The runtime system library is linked
with the compiled ECharts machine modules and other compiled host
language modules to form an executable program. For information on
building the ECharts SDK see Appendix A.
2.1
Hello World!
Here’s an example of how to program, compile, and run the canonical
“Hello World!” program as an ECharts machine. In this example and
all subsequent examples, we employ Java as the ECharts host language.
First, create the ECharts machine itself in a file examples/Example0001.ech. If you feel like cheating a bit, you’ll find this
file and all other example files mentioned in this document in the runtime/java/src/examples directory of the ECharts SDK.
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