In most of our code, we generally use HashMap.
Most of the operation we do:
· Prepare HashMap to process.
· Process the HashMap.
· Retrieve data from Map.
Following use-case needs to be avoided:
Most of the time to avoid NPE (NullPointerException) code is getting handled in below way:
dataMap.contains(key) ? dataMap.get(key) : someObject;
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Avoid using above as it may impact performance because both below APIs do same operation:
· containsKey()
· get(key)
SO optimized code for avoiding redundant Map processing:
Object mappedValue = dataMap.get(key); // fetch only once (mappedValue == null) ? someObject: mappedValue;
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This is definitely useful for dealing bigger DataSet.
Also don't forget to use collection.clear(); if data is no more required.
III
Best Regards,
Abhjeet.
