Structural Things
Anactive class
is a class whose objects own one or more processes or threads and therefore can initiate control activity. An active class is just like a class except that its objects represent elements whose behavior is concurrent with other elements. Graphically, an active
class is rendered as a class with double lines on the left and right; it usually includes its name, attributes, and operations.
活动类是类的对象拥有一个或多个过程或线程，而且可以启动控制活动．活动类的对象表现某个元素的行为与其它元素同时发生的事件，除此以外它与类很相似．在图形表现上，活动类同类一样是个矩形框，与类的图形不同的是，代表活动类的矩形框的左右两侧是双线条；它通常包含名称，属性和操作．
Acomponent
is a modular part of the system design that hides its implementation behind a set of external interface. Within a system, components sharing the same interfaces can be substituted while preserving the same logical behavior. The implementation of a component
can be expressed by wiring together parts and connectors; the parts can include smaller components. Graphically, a component is rendered like a class with a special icon in the upper right corner.
组件是系统设计期间模块化的部分，它的具体实现被封装 ，对外只提供外部接口集．在系统里面，组件中有着同样逻辑行为的接口可以相互替换．组件的实现可以通过连接在一起的部分和连接器表达出来；这个连接部分允许包含更小的组件．图形表现上，组件是由一个矩形框表示，矩形框的右上角带有一个特殊图标来标识出该图形是代表着一个组件．
The remaining two elements -- artifacts and nodes -- are also different. They represent physical things, whereas the previous five things represent conceptual
or logical things.
剩下工件和结点这两个元素，它们的不同点在于它们代表着物理元件，前面介绍的五个元件都代表着概念上或是逻辑上的元件．
UML的基础元件之架构元件(三)