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Reading files from app engine project running in eclipse

I am trying to read a file stored in my computer from the app engine project which I am debugging in eclipse. But I am getting security exception with the following error:
java.security.AccessControlException: access denied ("java.io.FilePermission" ""D:\PROJECTS\LocBiz-AppEngine\war\Key\locbiz_key.json"" "read")
at java.security.AccessControlContext.checkPermission(Unknown Source)
at java.security.AccessController.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkPermission(Unknown Source)
How do I read the file?

Put the files you want to read on the classpath and use the class loader to read them in
Foo.class.getResource("myfile");
A Java App Engine application's access to the classes in the Java standard library is limited to the whitelisted classes.

Netbeans 7.3.1 Cannot establish a connection to jdbc:derby

Recently I'm working on this little project with Java EE and I need to use derby database , but every time I go to service->Database and try to connect to my jdbc:derby I get this error :
Unable to connect. Cannot establish a connection to jdbc:derby://localhost:1527//sample using org.apache.derby.jdbc.ClientDriver (java.netConnectException : Error connecting to server localhost on port 1527 with message Connection refused: connect.).
and this exception :
Wed Oct 29 15:05:26 EET 2014 : access denied ("java.net.SocketPermission" "localhost:1527" "listen,resolve")
java.security.AccessControlException: access denied ("java.net.SocketPermission" "localhost:1527" "listen,resolve")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:457)
at java.security.AccessController.checkPermission(AccessController.java:884)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.SecurityManager.checkListen(SecurityManager.java:1131)
at java.net.ServerSocket.bind(ServerSocket.java:374)
at java.net.ServerSocket.<init>(ServerSocket.java:237)
at javax.net.DefaultServerSocketFactory.createServerSocket(ServerSocketFactory.java:231)
at org.apache.derby.impl.drda.NetworkServerControlImpl.createServerSocket(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl.access$000(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl$1.run(Unknown Source)
at java.security.AccessControWed Oct 29 15:05:26 EET 2014 : access denied ("java.net.SocketPermission" "localhost:1527" "listen,resolve")
java.security.AccessControlException: access denied ("java.net.SocketPermission" "localhost:1527" "listen,resolve")
at java.security.AccessContrller.doPrivileged(Native Method)
at org.apache.derby.impl.drda.NetworkServerControlImpl.blockingStart(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl.executeWork(Unknown Source)
at org.apache.derby.drda.NetworkServerControl.maiolContext.checkPermission(AccessControlContext.java:457)
at java.security.AccessController.checkPermission(AccessController.java:884)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.SecurityManager.checkListen(SecurityManager.java:1131)
at java.net.ServerSocket.bind(ServerSocket.java:374)
at java.net.ServerSocket.<init>(ServerSocket.java:237)
at javax.net.DefaultServerSocketFactory.createServerSocket(ServerSocketFactory.java:231)
at org.apache.derby.impl.drda.NetworkServerControlImpl.createServerSocket(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl.access$000(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.derby.impl.drda.NetworkServerControlImpl.blockingStart(Unknown Source)
at org.apache.derby.impl.drda.NetworkServerControlImpl.executeWork(Unknown Source)
at org.apache.derby.drda.NetworkServerControl.main(Unknown Source)
n(Unknown Source)
Any ideas how to fix it?

Did you already try the hint from here http://wiki.netbeans.org/JavaDB_grant_permissions
JDK 7u51 comes with some security improvements which are causing problems with starting Java DB on this Java version.
When you try to start DB from NetBeans you will probably get the Exception:
java.security.AccessControlException: access denied ("java.net.SocketPermission" "localhost:1527" "listen,resolve")
The same exception you will get while starting using script /db/bin/startNetworkServer
Because there is no suitable way to fix it on the NetBeans side and this should be fixed on the side of the Java DB.
There are several ways how to deal with this problem. I will mention only the easiest way. You have to start DB manually from command line.
Start Java DB with -noSecurityManager argument.
<JDK 7u51 location>/db/bin/startNetworkServer -noSecurityManager

you need to add start page in project property.
Open Project property. Then choose tab run. Then add your project start page to relative URL text box. Mine is "/index.jsp".
Sorry if i have some mistake in english grammar.

Use applet in html?

I would like to use this applet this applet in a html document. In the example on this site they use :
<applet code="de.wim.outldd.examples.DragDropTest_Applet"
width="150" height="150" alt="Applet1" archive="soutldd.jar">
</applet>
It does not work when I try it. My HTML document is in the middle of the extracted directory. How can I use the applet in html, somebody please try this.
THe error in the console
java.lang.RuntimeException: java.lang.ExceptionInInitializerError
at sun.plugin2.applet.Plugin2Manager.createApplet(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ExceptionInInitializerError
at de.wim.outldd.OutlookDD.init(OutlookDD.java:73)
at de.wim.outldd.examples.DragDropTest_Applet$1.run(DragDropTest_Applet.java:29)
at java.security.AccessController.doPrivileged(Native Method)
at de.wim.outldd.examples.DragDropTest_Applet.<init>(DragDropTest_Applet.java:26)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$12.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.security.AccessControlException: access denied (java.util.PropertyPermission java.io.tmpdir 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.checkPropertyAccess(Unknown Source)
at java.lang.System.getProperty(Unknown Source)
at de.wim.outldd.OutlDDNativeLib.loadDllFromResource(OutlDDNativeLib.java:135)
at de.wim.outldd.OutlDDNativeLib.loadDll(OutlDDNativeLib.java:104)
at de.wim.outldd.OutlDDNativeLib.<clinit>(OutlDDNativeLib.java:62)
... 19 more
Exception: java.lang.RuntimeException: java.lang.ExceptionInInitializerError

Your applet is trying to read the temp directory value from the java.io.tmpdir system property which is previleged. Applets run in a sandbox environment with restricted permissions beacause of security reasons. To fix it, override the default security policy to allow your applet to read the property by setting the property permission - java.util.PropertyPermission, on the property. To override default permissions define the policy in your user home's .java.policy file. It is recommended that you edit your user specific policy file and not the global policy file under your JRE security directory. Refer the template below:
grant codeBase "<code base>" {
permission <type> "<target>", "<actions>";
permission <type> "<target>", "<actions>";
...
};
For eg.
grant codeBase "http://geosim.cs.vt.edu/geosim/-" {
permission java.util.PropertyPermission "java.io.tmpdir", "read";
...
};
Edited:
I noticed that you already have the applet link specified in your post at the top. So, I am giving a step by step guide to get you started.
Here you go -
Copy $JRE_HOME/lib/security/java.policy file to your user home (on windows it is c:\users\< user name>) as .java.policy file. Please note the preceding "." in the file name.
Add the following lines to the end of .java.policy file:
grant codeBase "http://www.wilutions.com/outldd/-" {
permission java.security.AllPermission;
};
Run the applet in an appletviewer as follows and see if it works.
appletviewer http://www.wilutions.com/outldd/example.html
Please note that I am specifying all permissions to the applet for sake the of geting you started but it is potentially insecure to grant all permmissions. You should grant only the required permissions. So, I leave it to you to figure it out.

Have you followed the guide found here and are you sure the specified paths are correct in relation to your directory/html page?
Also what about applet JAR file soutldd.jar path is this correct?

go to Java preferences->advance and turn Java console on so that you can see what is happening on loading your applet in HTML.
in windows
java preferences: control panel -> java

Java - How to get permission in Java Web Start

Hi managed to create the jar and .jnlp files for my Java application but running into trouble when it runs. Launches okay with Java Web Start but I think I need to do something
extra as normally when I run it it doesn't ask for permission to access the HD for file I/O.
Would appreciate some help and advise to know what to do to get the permission rights i.e. what do I have to do is it something I have to do to all my classes not sure. The error
message I get in Java Web Start is as below.
Exception in thread "AWT-EventQueue-0" java.security.AccessControlException:
access denied (java.io.FilePermission StockDatabase;Stocks.dat 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.File.exists(Unknown Source)
at StockCodeDatabase.<init>(OptraderSA.java:782)
at OptraderSA.actionPerformed(OptraderSA.java:136)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.AbstractButton.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(Unknown Source)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(Unkno

You need to sign your JNLP file and configure the <security> element, as discussed here.

Add the following to your JNLP:
<security>
<all-permissions/>
</security>
This will pop a dialogue asking the user the give the necessary permission to your app.

If you want access to the file system you need to change your JNLP file to include:
<security><all-permissions/></security>
This requires you to also sign your jar files.
Another option is to package the file inside the jar as a resource and you don't have to do all that.

A quick way to solve java.security.AccessControlException

I have an applet which have to read a file from server. But I receive the following exception
java.security.AccessControlException: access denied (java.io.FilePermission \kb1.xml 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.File.isDirectory(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.connect(Unknown Source)
at sun.net.www.protocol.file.FileURLConnection.getInputStream(Unknown Source)
...
I tried to put a java.policy.applet file with permission granted for reading but it doesn't work.
I need a quick way to solve this problem. I have to specify that for making this applet I used java 6.

You said you want to read a file on the server, but the exception is caused by trying to read a file on the client (the machine that is running the applet).
You cannot read files from the server directly. You need to access them via HTTP or put them into the applet's jar file and load it from there.