Java 命名约定是否允许 `ClassName` 有两个首字母大写?

Does Java naming convension allow `AClassName` with two first capital letters?

我正在为 class 报告系统事件消息选择一个名称。可能的名称:

(1) SystemEventMessage //SystemEventMessageReportController 太长了
(2) EventMessage //与太阳发生冲突。plugin2.message.EventMessage
(3) Message //与多个classes
冲突 (4) EMessageSMessage // 首选方式

是否允许 class 名称如 EMessage?这个名字有什么潜在的问题?

这是一种常见的命名方式。 Java Swing 有核心 类 HBox, VBox, 等等

即使它被使用(正如 Victor 在他的回答中所写),也不意味着它被 Java code convemtions 推荐:

Class names should be nouns, in mixed case with the first letter of each internal word capitalized. Try to keep your class names simple and descriptive. Use whole words-avoid acronyms and abbreviations (unless the abbreviation is much more widely used than the long form, such as URL or HTML).