Java Reference
In-Depth Information
standard input stream,
System.in
, is used after wrapping it in an
In-
putStreamReader
, which converts an input byte stream into an input char-
acter stream; if a filename is provided, an object of type
FileReader
is
created, which is a subclass of
Reader
.
The
for
loop counts the total number of characters in the file and the
number of spaces, using the
Character
class's
isWhitespace
method to
test whether a character is whitespace. At the end, the results are prin-
ted. Here is the output of the program when used on itself:
453 chars, 111 spaces
20.3.2.
Writer
The abstract class
Writer
provides a stream analogous to
OutputStream
but designed for use with characters instead of bytes. The methods of
Writer
essentially mirror those of
OutputStream
, but add some other use-
ful forms of
write
:
public void
write(int ch)
throws IOException
Writes
c
h as a character. The character is passed as an
int
but
only the lowest 16 bits of the integer are written. This method
blocks until the character is written.
public abstract void
write(char[] buf, int offset, int count)
throws
IOException
Writes part of an array of characters, starting at
buf[offset]
and writing
count
characters. This method blocks until the
characters have been written.
public void
write(char[] buf)
throws IOException
