Read file from local disk (little bit urgent, thanks)

Question

Hi all. We're facing a problem using a signed applet. We think it's a matter of versions of the java plugin. The fact is that with version 1.4.0 there's no problem on reading a local file from the applet. Not the same can be said when using version 1.4.2_0X. In fact the applet crashes throwing the following exception:
java.security.AccessControlException: access denied (java.io.FilePermission C:\Documents and Settings\rgallart\Mis documentos\aaa.rtf read)
     at java.security.AccessControlContext.checkPermission(Unknown Source)
     at java.security.AccessController.checkPermission(Unknown Source)
     at java.lang.SecurityManager.checkPermission(Unknown Source)
     at java.lang.SecurityManager.checkRead(Unknown Source)
     at java.io.FileInputStream.<init>(Unknown Source)
     at appletupload.AppletUpload.fitxerOk(AppletUpload.java:265)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
     at java.lang.reflect.Method.invoke(Unknown Source)
     at sun.plugin.com.MethodDispatcher.invoke(Unknown Source)
     at sun.plugin.com.DispatchImpl.invokeImpl(Unknown Source)
     at sun.plugin.com.DispatchImpl$2.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at sun.plugin.com.DispatchImpl.invoke(Unknown Source)
java.lang.Exception: java.security.AccessControlException: access denied (java.io.FilePermission C:\Documents and Settings\rgallart\Mis documentos\aaa.rtf read)
     at sun.plugin.com.DispatchImpl.invokeImpl(Unknown Source)
     at sun.plugin.com.DispatchImpl$2.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at sun.plugin.com.DispatchImpl.invoke(Unknown Source)There was no need to configure any policy file in the local system with version 1.4.0 and also writing a file to disk works fine. Is it necessary to do so on higher versions?
Any help would be appreciated.
Thanks for your time.

Answer 1

Hola Ramon!
java.security.AccessControlException: access denied
(java.io.FilePermission C:\Documents and Settings\rgallart\Mis documentos\aaa.rtf read)I don't know much about signed applets, but I've seen this exception very
recently with my own work with unsigned applets.
If you put this in your policy file, all access problems should go away, whether your
applet is signed or unsigned. But this would apply to any applet that uses the
same policy file.
grant {
permission java.security.AllPermission;
If you want something less radical and more sophisticated, check out the syntax here: http://java.sun.com/j2se/1.3/docs/guide/security/PolicyFiles.html
Another way round the access problem is to locate the file to be accessed on the same
host as your applet, and open it as an url resource. This works with an unsigned applet
with default security, so it whould work with a signed applet too. (In my so called logic at least :)
I can post a code example of this here if you want one.
There was no need to configure any policy file in the
local system with version 1.4.0 and also writing a
file to disk works fine. Is it necessary to do so on
higher versions?Honestly, I don't know. But it looks that way, doesn't it?
Matilda