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NullPointerException: name can't be null  RSS feed

 
Ranch Hand
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Good day!
I have this code which I want to implement in an Applet and put in on a JSP page after.



But after running this program, I get this error:

java.lang.NullPointerException: name can't be null
at java.io.FilePermission.init(Unknown Source)
at java.io.FilePermission.<init>(Unknown Source)
at java.lang.SecurityManager.checkDelete(Unknown Source)
at javax.comm.CommPortIdentifier.getPortIdentifiers(CommPortIdentifier.java:70)
at com.amkor.stripmap.ReadWriteC.getPorts(ReadWriteC.java:38)
at com.amkor.stripmap.ReadWriteC.<init>(ReadWriteC.java:78)
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.applet.AppletPanel.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)


What is lacking in my code?

Thanks.
 
Rancher
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In order to perform socket I/O applets generally need to be signed; is that the case?

As an aside, you should remove the constructor, and move everything that's in it into an init() method.
[ October 19, 2007: Message edited by: Ulf Dittmer ]
 
Darren Alexandria
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thank you for your reply!

God bless!
 
It is sorta covered in the JavaRanch Style Guide.
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