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need help copying hashmaps

 
Greenhorn
Posts: 21
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hi all.
i need to have 2 hashmaps so i can write to a log file what the records look like "before" the update.
i have oldHashMap and newHashMap.

my problem is when i update newHashMap, and use OldHashMap to write to the log file, the "new" values are written to the log file.

what's the best way to copy (by value?) the values in oldhashMap to newHashMap.

I tried putAll() but did not work.

thanks.
 
Ranch Hand
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I think you would need to manually iterate through the contents of the old hash map, clone each item, and add each clone to the new hash map.
 
Rancher
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Look at cloning.
Your problem says that both hashmaps refer to the SAME set of objects. You need to make clones of the objects in the one hashmap and save the clones in the other.
 
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