Java IO.pdf - Nguyen Dang Binh

}
Java I/O
public int read(char[] text, int offset, int length) throws IOException {
}
int numRead = 0;
for (int i = offset; i < offset+length; i++) {
int temp = this.read();
if (temp == -1) break;
text[i] = (char) temp;
numRead++;
}
return numRead;
public long skip(long n) throws IOException {
}
char[] c = new char[(int) n];
int numSkipped = this.read(c);
return numSkipped;
15.11.2 The FilterWriter Class
The FilterWriter class has a single constructor and no other unique methods:
protected FilterWriter(Writer out)
The out argument is the writer to which this filter is chained. This reference is stored in a
protected field called out, to which text sent through this filter is written.
protected Writer out
Since FilterWriter is an abstract class, only subclasses may be instantiated. Therefore, it
doesn't matter that the constructor is protected, since it may only be invoked from subclass
constructors anyway. FilterWriter provides the usual collection of write(), close(), and
flush() methods:
public void write(int c) throws IOException
public void write(char[] text, int offset, int length) throws IOException
public void write(String s, int offset, int length) throws IOException
public void flush() throws IOException
public void close() throws IOException
These all simply invoke the equivalent method in the out field with the same arguments. For
example:
public void close() throws IOException {
out.close();
}
In general, each subclass will have to override at least the three write() methods to perform
the filtering.
There are no subclasses of FilterWriter in the core API. Example 15.8, SourceWriter, is
an example of a FilterWriter that converts Unicode text to \u-escaped ASCII. The big
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