面向对象的特征

String 和StringBuffer的区别

运行时异常与一般异常有何异同？

以下程序使用内部类实现线程，对j增减的时候没有考虑顺序问题。

-Object-oriented features of the difference between String and StringBuffer run-time anomalies and anomalies of the similarities in general? The following types of procedures to achieve the use of internal threads on j does not take time to change the order of the problem.