I provide this list both to illustrate the complexity of J2EE and to provide a crude map of the order in which you should proceed in learning these technologies. The important technologies are.

我提供这份清单既是为了解释J2EE的复杂性，也是为了提供一份帮助您继续学习这些技术的粗略的地图。

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To create a heat map, simply take any model of the system and shade or colour different areas of the model to indicate the ease or complexity of working on different each area.

要绘制热点图，任取一个系统模型，把模型中的每个区域用不同的颜色，以此来表明各个区域上工作的难易程度。

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This paper introduces a map sort algorithm with extra memory cost, its time complexity is o (n).

本文介绍了映射式排序算法，这种算法附加一定的存储开销，时间复杂性为O (N)。

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Researchers map such smiles to study where our emotions come from, their complexity and the impact they have on social relationships.

WSJ: Stress-Busting Smiles