为什么考OCA
简单地说就是通过考试驱动学习，这样目的性强，学起来比较专注，高效。 针对考试的学习，有时候也是很有用的。引用下面的话：
That’s not to say that preparing for the exam won’t help you become a better Java programmer!
On the contrary, even the most experienced Java developers often claim that having to prepare for the certification exam made them for more knowledgeable and well-rounded programmers than they would have been without the exam-driven studying.
不管怎么说，已经预约好考试了，一个月之后拿下考试，目标是 100% 的正确率。
参考书的内容目录
- Declaration and Access Control
- Object Orientation
- Assignments
- Operators
- Flow Control and Exception
- Strings, Arrays, ArrayList, Dates, and Lambdas
阅读建议
- 留意那些 Two-Minute Drill 部分，多读几次。
- 重读所有 Exam Watch notes.
- 重做所有 Self Tests.
- 完成所有练习。
- 写很多很多 Java 代码。（不要用 IDE）
可是后来我选择了 Scott 和 Jeanne 的书，后面的文章有提到。