I've used final keyword with class, method, fieldsbut this the first i'm seeing something like this
final Customer c=new Customer();
could anyone help me to get what is the use of this?
Asked
Active
Viewed 213 times
-1
Venkatesh Ayyavu
- 11
- 1
-
https://docs.oracle.com/javase/tutorial/java/javaOO/classvars.html – Suresh Atta Sep 26 '15 at 18:01
-
@sᴜʀᴇsʜᴀᴛᴛᴀ what you cannot change/reassign is the value of `c`. – Luiggi Mendoza Sep 26 '15 at 18:02
-
Declaring a variable as `final` will never allow it to be re-instanced. So in this case, the code `c = SomeOtherCustomerObject;` would throw an error. – CollinD Sep 26 '15 at 18:02
-
@LuiggiMendoza Ok. There you go. – Suresh Atta Sep 26 '15 at 18:03
1 Answers
1
it is constant reference - you cannot change its value it can be assigned only once when being defined
an example:
final String string = "initial value";
string += " some new content"; //here compiler will raise an error due to you cannot change final value
m.antkowicz
- 13,268
- 18
- 37
-
can't we create clone object using c!! i'd tried but throws java.lang.CloneNotSupportedException – Venkatesh Ayyavu Sep 26 '15 at 18:33
-
it seems to be not about **final** but Customer class. Due to [CloneNotSupportedException reference](http://docs.oracle.com/javase/7/docs/api/java/lang/CloneNotSupportedException.html) - "Thrown to indicate that the clone method in class Object has been called to clone an object, but that the object's class does not implement the Cloneable interface." – m.antkowicz Sep 26 '15 at 18:56