Assume, for example, that an ESB communicates with more than one back-end service provider (which, of course, is virtually always the case), and that different providers have different timeouts.
例如，假设一个ESB与多个后端服务提供程序通信(当然，事实总是这样)，不同的提供程序有不同的超时。
This article assumes that the back-end database, in this case DB2, is already installed and in-use.
本文假设后端数据库（在这里是 DB2）已经安装好了。
The standard for compiler design is to break it in two modules: the front end that reads and decodes the input file, and the back end that produces the code or, in this case, the table class.
编译器的设计标准是将其分成两个模块：前端和后端，前端读取输入文件并对该文件进行解码，后端生成代码，或者在这种情况下生成 table 类。
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