Java applet writes to file on client, no signing necessary

Hi,
I wonder if this is a feature or bug:
I download and execute in my browser an unsigned applet/jar myCharts.jar from server. The applet references classes from package org.jfree.chart, which are not packed in myCharts.jar downloaded from server, but are locally stored on client in jre/lib/ext/jfreechart.jar (and therefore JVM running the applet loads and uses these local classes from local jar).
The applet can write the file to client disk without any problem using classes from locally loaded jfreechart.jar. If I merge both jars into a big one and load it through network, file write access is forbidden.
I am using JRE 1.5.0.3 for Windows and default java_policy file with 2 permissions added:
permission java.lang.RuntimePermission "accessDeclaredMembers";
permission java.lang.reflect.ReflectPermission "suppressAccessChecks";
Is it a bug, or feature ?
According to my opinion these 2 permissions should not result in applet ability to write files using locally loaded classes.
Thanks for your answer
Martin

The following is a duplicate posting in reponse to similar question:
http://forum.java.sun.com/thread.jsp?forum=4&thread=200482&start=0&range=30#735223
In short, you cannot write to a server without help from servier-side software such as a servlet, cgi, ASP, etc.
If you go with something like an Oracle database on your server, it's a non-issue because the seucirty aspects are taken care of for you.
V.V.

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Java applet writes to file on client, no signing necessary

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