I/O Objectives Questions

[Joel Carklin]

Hi All,
Tried posting this on the I/O streams group but got no response so matbe this is where I was supposed to ask, or maybe they're just stupid questions ??
Please can someone help me clarify the following exam objectives, all from Section 11 The java.io PACKAGE
Distinguish between conditions under which platform default encoding should be used and conditions under which a specific conversion should be used?

I have no idea when specific conversion should be used, rather than the default encoding? Unless it has something to do with
writing programs for languages other than english?

Select valid constructor arguments for FilterInputStream and
FilterOutputStream subclasses *from a list of classes in the java.io.package*

It's the part between the astrixes I am not sure about: The subclasses of the filter stream all accept either an InputStream or OutputStream (or any of their subclasses) as valid constructor arguments and in some cases a buffer size; does
'from a list of classes in the java.io.package' imply more than this? Am I missing something?

Describe the permanent effects on the file system of constructing and using FileInputStream, FileOutputStream, and RandomAccessFile objects.

Does this refer to using FileOutputStream, and RandomAccessFile to create actual files or directories on the actual filesystem? Is this a 'permanent effect'? What permanent effect does
FileInputStream have?
The following classes (among others) don't 'seem' to be covered in the exam objectives; does this mean we definitly will NOT get any questions relating specifically to them, or are the objectives not that specific, more like guidelines. (I understand that I have to know how to use them anyway,
but must I know their specifics for the exam?):
?Not covered in Objectives?
class java.io.PushbackInputStream
class java.io.ObjectInputStream
(implements java.io.ObjectInput,
java.io.Object Stream Constants)
class java.io.PipedInputStream
class java.io.SequenceInputStream
Thanks in advance
Joel

[Mapraputa Is]

Dylan Walsh's Exam Revision document is very useful (for I/O in particular): http://indigo.ie/~dywalsh/certification/index.htm
About classes you mentioned, I did not get any questions about them on the exam and I've never heart somebody gets them. If you know what they were designed for, that should be enough.