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They had given one progam
final HashMap hm=new HashMap();
public void show()
{
hm.put("name",value);
}
in this prg here the final hashtable value can be changed in
put method,its the prg run?

Question Posted / abhinav mutreja

Answer Posted / abhinav mutreja

Thats Correct that contents of the HashMap can be changed
even if HashMap is declared as final.
If you contents also should not get changed then you can use

Map hm = Collections.unmodifiableMap(new HashMap());
here if you do
hm.put(1,"Hi");

then it would give Runtime Exception :-
Exception in thread "main"
java.lang.UnsupportedOperationException
at java.util.Collections$UnmodifiableMap.put
(Unknown Source)

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