Make my Program read/write to a local file

Hello,
I'm new to java but I have a workable program. I am trying to make the program read/write to a file. Right now all of my information is stored temp. so when my program crashes all of the info is lost. So if I could have it read/write to a local file then the information wouldn't get lost. Can someone please help me with this?
Thanks

http://java.sun.com/docs/books/tutorial/essential/io/index.html

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See iamge below.
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(I have split the image to save horizontal space).
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> All VMs are using dynamic disks (as recommended by Microsoft).
If this is a testing environment, it’s okay, but if this a production environment, it’s not recommended. Fixed VHDs are recommended for production instead of dynamically expanding or differencing VHDs.
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http://technet.microsoft.com/en-us/library/ee941151(v=WS.10).aspx
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Check that and modify cluster configuration, monitor it and give us feedback for further troubleshooting.
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Deployments and Tests in an iSCSI SAN
http://technet.microsoft.com/en-US/library/bb649502(v=SQL.90).aspx
Hope this helps!
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Make my Program read/write to a local file

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