Signed Applet Trouble.

Question

hi,
Lately have been working on signing of applets, now by default
applets are not allowed to access system resources, i.e files, etc,
for obvious reasons. So if one has to access these resources through
applet, the applet needs to be signed. Now i have signed the applet,
even after doing that when i try to access the files(most of them
are XML and property files), it gives me access denied error.
The weird part is that it works perfectly fine in JRE1.4.1_01,
where as it gives error in the later versions of Java i.e
JRE1.4.2_01 or for that matter even in the latest version i.e
JRE1.4.2_02.
So here i need to verify, that is this really a bug, or has Java
enhanced its security constraints.
In either case i need to find a consistent and optimized solution
for the same.Here in i have found a solution, using
Java.security.AccessController and its doPrivileged method.
Thanks in Advance
Regards
Vikram

Answer 1

This worked fine on my win 2k machine with 1.4.2_01:
HTML file (called test.htm):
<APPLET CODE="test.class" archive="sTest.jar" WIDTH=0 HEIGHT=0></APPLET>
Applet code (called test.java)"
import java.util.Properties;
import java.applet.Applet;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
public class test extends Applet implements Runnable {
            public test(){
                new Thread(this).start();
         public static void main(String argv1[]) {
              new test();
            public void run(){
                 try{
                      System.out.println(System.getProperty("java.version"));
                      System.out.println(System.getProperty("user.home"));
                     File fle = new File(System.getProperty("user.home") +
                          System.getProperty("file.separator") + "testFile.txt");
               System.out.println("Created file: " + fle.toString());
                        FileOutputStream outFile = new FileOutputStream(fle);
               outFile.write("hello, this is written".getBytes());
               System.out.println("Written to file: " + fle.toString());
               outFile.close();
                     FileInputStream inFile = new FileInputStream(fle);
               System.out.println("Opened file: " + fle.toString());
                     int b = inFile.read();
                  while(b!=-1){
                          System.out.print((char) b);
                          b = inFile.read();
               System.out.println("This was te content of file: " +
                    fle.toString());
                      inFile.close();
                 }catch(Exception e){
                      e.printStackTrace();
}The batchfile that signes the applet (password is password):
rem del *.cer
rem del *.com
rem del *.jar
rem del *.class
javac test.java
keytool -genkey -alias alias -keypass password -keystore keystore.com -storepass password
jar cf0 test.jar test.class
jarsigner -keystore keystore.com -signedjar sTest.jar test.jar alias -storepass password -keypass password
keytool -export -keystore keystore.com -alias alias -file test.cer -storepass password -keypass password
keytool -import -alias alias -file test.cer -keystore keystore.com -storepass password -keypass password
Output:
1.4.2_01
C:\Documents and Settings\user
Created file: C:\Documents and Settings\user\testFile.txt
Written to file: C:\Documents and Settings\user\testFile.txt
Opened file: C:\Documents and Settings\user\testFile.txt
hello, this is writtenThis was te content of file: C:\Documents and Settings\user\testFile.txt