Naming convention for CFBundleSignature and CFBundleIdentifier
I am wondering how do I know what name I should give for my CFBundleSignature and CFBundleIdentifier.  I believe these are supposed to be unique identifier so do I have to somehow get these names from apple?  Say my app is called javaapp and comes from the website javaapp.  Should my CFBundleIdentifier be com.javaapp.javaapp?  What 4 letters should I use for my CFBundleSignature?  
Naming convention for CFBundleSignature and CFBundleIdentifier
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I am wondering how do I know what name I should give for my CFBundleSignature and CFBundleIdentifier.  I believe these are supposed to be unique identifier so do I have to somehow get these names from apple?  Say my app is called javaapp and comes from the website javaapp.  Should my CFBundleIdentifier be com.javaapp.javaapp?  What 4 letters should I use for my CFBundleSignature?  