Tool in java to periodically scans a file hierarchy

[rammie singh]

Hi,

I want to develop a tool in java which periodically scans a file hierarchy and stores any changes which has happened in the file. This is an assignment given to us.
Following are the features this tool can provide

The tool allows the user to:

Build a history of all the files that have changed since the last time a scan was done

designate a snapshot as a FileSet - there should be the ability to sign FileSets and mark them as restore points or reference FileSets

allows me to compare the current scan with a FileSet to see what deltas exist

each file is signatured - using a hash algorithm (like MD5)

a copy of the file should be stored for future retrieval

each file should have a file_key that identifies it (except for zero length files or device files in UNIX - which will have to be treated specially)

each file that is stored should be encryptable so that it is not modifiable - this allows for repudiation and file validation

I tried searching a similar tool with sourcecode for reference but did not find one.
If any one can please guide if there is similar tool available and whose code can be referenced.Thanks.
Sorry if i have posted in wrong section. I was not sure where to exactly paste this query.

[Stephan van Hulst]

Personally I'm not aware of such a tool in Java. You might find some tools that do some of these separate tasks though, like a diff tool to make deltas. The rest sounds like you could implement it yourself with a few hints.

A few remarks:

rammie singh wrote:

each file is signatured - using a hash algorithm (like MD5)

This is not a signature, this is a hash. You can't use hash functions to sign a file, because you can't authenticate them.

each file that is stored should be encryptable so that it is not modifiable - this allows for repudiation and file validation

You don't want to encrypt files in order to achieve non-repudiation and validation. You need to digitally sign them.