我应该看起来更好。来自PrintWriter的javadoc：

I should have looked better. From the javadoc of PrintWriter:

此类中的方法永远不会抛出I / O
异常，尽管它的一些
建设者可以。客户可以通过调用{@link
#checkError checkError（）}来查询
是否有任何错误发生
。

Methods in this class never throw I/O exceptions, although some of its constructors may. The client may inquire as to whether any errors have occurred by invoking {@link #checkError checkError()}.