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i was almost worried

 
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i finally got a computer again after many years. i ran a program i wrote in 2004 and noticed a logic error
i tried a fix and compiled from the command line. the compiler compiled it but gave me a warning and said to recompile with -Xlint for details.
it turned out the warnings were almost all about generics (which didn't exist in 2004). not saying type, and then later casting.
what a relief.

on the less meaningless side, one warning i don't quite understand.
warning: [serial] serializable class Maze has no definition of serialVersionUID

any idea what that means?
 
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If a serializable class (a class the implements the Serializable marker interface) includes a static long variable named serialVersionUID, Java's serialization machinery uses it to identify class versions. It lets you make trivial changes to a class without breaking compatibility with old serialized data. Best practice is to define this variable in any serializable class. It's not an error to neglect it though.
 
Randall Twede
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thanks for the succinct, easy to understand answer Ernest.
i guess i somehow implemented serializable by either extending JFrame or implementing ActionListener.
public class Maze extends JFrame implements ActionListener.
 
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.. and welcome back, Randall!
 
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Sumit Bisht wrote:.. and welcome back, Randall!


 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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