Does it make sense to define a final String in Java?

java string final
Campa picture Campa · Apr 19, 2012 · Viewed 57.9k times · Source

Possible Duplicate:
String and Final

From http://docs.oracle.com/javase/6/docs/api/java/lang/String.html I can read that:

Strings are constant; their values cannot be changed after they are created.

Does this mean that a final String does not really make sense in Java, in the sense that the final attribute is somehow redundant?

Answer

Mike Kwan picture Mike Kwan · Apr 19, 2012

The String object is immutable but what it is is actually a reference to a String object which could be changed.

For example:

String someString = "Lala";

You can reassign the value held by this variable (to make it reference a different string):

someString = "asdf";

However, with this:

final String someString = "Lala";

Then the above reassignment would not be possible and would result in a compile-time error.

Related questions

Why is the String class declared final in Java?

From when I learned that the class java.lang.String is declared as final in Java, I was wondering why that is. I didn't find any answer back then, but this post: How to create a replica of String class …

Read More
What are the benefits of using identical String literals instead of a final variable?

I've come across a class that includes multiple uses of a string literal, "foo". What I'd like to know, is what are the benefits and impact (in terms of object creation, memory usage and speed) of using this approach instead …

Read More
Comparing strings with == which are declared final in Java

I have a simple question about strings in Java. The following segment of simple code just concatenates two strings and then compares them with ==. String str1="str"; String str2="ing"; String concat=str1+str2; System.out.println(concat=="string"); The …

Read More