Java/Security/Security Applet

Applet write file and policy file

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/**
 * By default, this applet raises a security exception, unless you configure
 * your policy to allow applets from its location to write to the file
 * "writetest".
 */
import java.applet.Applet;
import java.awt.Graphics;
import java.io.BufferedOutputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
public class WriteFile extends Applet {
  String myFile = "writetest";
  File f = new File(myFile);
  DataOutputStream dos;
  public void init() {
    String osname = System.getProperty("os.name");
  }
  public void paint(Graphics g) {
    try {
      dos = new DataOutputStream(new BufferedOutputStream(
          new FileOutputStream(myFile), 128));
      dos.writeChars("Cats can hypnotize you when you least expect it\n");
      dos.flush();
      g.drawString("Successfully wrote to the file named " + myFile
          + " -- go take a look at it!", 10, 10);
    } catch (SecurityException e) {
      g.drawString("writeFile: caught security exception: " + e, 10, 10);
    } catch (IOException ioe) {
      g.drawString("writeFile: caught i/o exception", 10, 10);
    }
  }
}