Java IO.pdf - Nguyen Dang Binh

public StreamedTextArea(String text, int rows, int columns) {
this(text, rows, columns, SCROLLBARS_BOTH);
}
Java I/O
public StreamedTextArea(String text, int rows, int columns, int
scrollbars) {
super(text, rows, columns, scrollbars);
setEditable(false);
}
}
public OutputStream getOutputStream() {
return theOutput;
}
class TextAreaOutputStream extends OutputStream {
}
public synchronized void write(int b) {
// recall that the int should really just be a byte
b &= 0x000000FF;
}
// must convert byte to a char in order to append it
char c = (char) b;
append(String.valueOf(c));
public synchronized void write(byte[] data, int offset, int length) {
append(new String(data, offset, length));
}
The TextAreaOutputStream inner class is quite simple. It extends OutputStream and thus
must implement the abstract method write(). It also overrides the primary array write()
method to provide a more efficient implementation. To use this class, you simply add an
instance of it to a container like an applet or a window, much as you'd add a regular text area.
Next you invoke its getOutputStream() method to get a reference to the output stream for
the area, then use the usual write() methods to write into the text area. Often these steps will
take place at different times in different methods.
Figure 2.1 shows a program using a StreamedTextArea to display data downloaded from
http://www.oreilly.com/. The application in this picture will be developed in Chapter 5.
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