Java Applet输出文件

Question

I am trying to create a Java Applet that outputs information to a text file located in the same directory as the java applet. I understand Java Applets are not ideal, but I have spent a great deal of time on this and if possible want to solve this through applets. Here is some of my code on how I could read code from a file into a text box. I assume it would be something similar to this, but outputted.

public void readFile() {
  String line;
  URL url = null;
  try {
     url = new URL(getCodeBase(), fileToRead);
  }
  catch(MalformedURLException e) {
  }
  try {
     InputStream in = url.openStream();
     BufferedReader bf = new BufferedReader
     (new InputStreamReader(in));
     strBuff = new StringBuffer();
     while((line = bf.readLine()) != null){
        strBuff.append(line + "\n");
     }
     a1.append("File Name : " + fileToRead + "\n");
     a1.append(strBuff.toString());
  }
  catch(IOException e) {
     e.printStackTrace();
  }
}

Answer 1

If you want an applet to store data on the local machine, from 6u10 the javax.jnlp.PersistenceService is available.

or on your local machine...

java.io.File file = new java.io.File(System.getProperty("user.home"), "yourfile.txt");

---

You must have it signed, otherwise...

Keep in mind that from an Applet, you cannot directly write to the server's file system. You can issue a request to the server that causes the server to write to its own file system, but an Applet does not have a way to write to a file system on a remote machine.

A signed Applet has every right to write to the local file system of the person running the Applet. If you are writing to the "current directory" (rather than an absolute full path), then make sure you know what directory the Applet is running in. Otherwise you may indeed create a file, but not be able to find it!

EDIT

Signed Applet Tutorial