import java.awt.*;
import java.awt.event.*;
import java.io.*;
public class RedirectedFrame extends Frame {
TextArea aTextArea = new TextArea();
PrintStream aPrintStream =
new PrintStream(
new FilteredStream(
new ByteArrayOutputStream()));
boolean logFile;
RedirectedFrame(boolean logFile) {
this.logFile = logFile;
System.setOut(aPrintStream);
System.setErr(aPrintStream);
setTitle("Error message");
setSize(500,300);
setLayout(new BorderLayout());
add("Center" , aTextArea);
displayLog();
addWindowListener
(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
dispose();
}
}
);
}
class FilteredStream extends FilterOutputStream {
public FilteredStream(OutputStream aStream) {
super(aStream);
}
public void write(byte b[]) throws IOException {
String aString = new String(b);
aTextArea.append(aString);
}
public void write(byte b[], int off, int len) throws IOException {
String aString = new String(b , off , len);
aTextArea.append(aString);
if (logFile) {
FileWriter aWriter = new FileWriter("error.log", true);
aWriter.write(aString);
aWriter.close();
}
}
}
public void displayLog() {
Dimension dim = getToolkit().getScreenSize();
Rectangle abounds = getBounds();
Dimension dd = getSize();
setLocation((dim.width - abounds.width) / 2,
(dim.height - abounds.height) / 2);
setVisible(true);
requestFocus();
}
public static void main(String s[]){
try {
// force an exception for demonstration purpose
Class.forName("unknown").newInstance();
}
catch (Exception e) {
// for applet, always RedirectedFrame(false)
RedirectedFrame r = new RedirectedFrame(true);
e.printStackTrace();
}
}
}