Java IO.pdf - Nguyen Dang Binh

Java I/O
complete list of the ASCII characters between 32 and 127 that must be encoded. For readers
not familiar with Macintosh files, let me emphasize that this is purely for use inside Java.
Native Macintosh code and the native Mac interface use the actual characters. As well as the
characters listed here, all the upper 128 characters with their high bit set—that is, characters
like and © and é—must be encoded. A little surprisingly, control characters between and 31
are not encoded.
Table 12.2. Hex-Encoded Characters in Macintosh Filenames
Character Encoded As Decimal Value
space %20 32
# %23 35
% %25 37
/ %2f 47
< %3c 60
= %3d 61
> %3e 62
? %3f 63
@ %40 64
[ %5b 91
\ %5c 92
] %5d 93
^ %5e 94
` %60 96
{ %7b 123
| %7c 124
} %7d 125
~ %7e 126
You probably don't need to know about the encoding at this level of detail unless you're trying
to manipulate filenames manually—for example, walking directories by looking for separator
characters rather than calling getParent(). The more you let Java do the work for you, the
better off you'll be. As long as you use the methods of the File class rather than parsing
pathnames directly as strings, this encoding scheme should be transparent.
12.2.2 Relative Versus Absolute Paths
There are two ways to reference a file, relative and absolute. Absolute addressing gives a
complete path to a file, starting with the disk or root of the filesystem and working its way
down. C:\PUBLIC\HTML\ JAVAFAQ\INDEX.HTM, Macintosh HD:
public:html:javafaq:index.htm, and /public/html/javafaq/index.htm are all examples of
absolute paths. Relative addressing does not use a complete path to a file; instead, it specifies
the path relative to the current working directory. A relative pathname may point to a file in
the current working directory by giving its name alone; other times it may point to a file in a
subdirectory of the current working directory by giving the name of the subdirectory and the
name of the file, and it may point to the parent of the current working directory with the
double period (..).
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