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String.intern()

Amit Punjwani
Ranch Hand

Joined: Jul 10, 2000
Posts: 50
Could anyone tell me what does the method intern() of the String class actually do? Can anyone explain it with an example?
Ajith Kallambella
Sheriff

Joined: Mar 17, 2000
Posts: 5782
Here is what the API documentation says about the intern() method

Returns a canonical representation for the string object.
A pool of strings, initially empty, is maintained privately by the class String.
When the intern method is invoked, if the pool already contains a string equal to this String object as determined by the equals(Object) method, then the string from the pool is returned. Otherwise, this String object is added to the pool and a reference to this String object is returned.
It follows that for any two strings s and t, s.intern() == t.intern() is true if and only if s.equals(t) is true.
All literal strings and string-valued constant expressions are interned. String literals are defined in �3.10.5 of the Java Language Specification
Returns:
a string that has the same contents as this string, but is guaranteed to be from a pool of unique strings.

I wrote a small program to help you understand this.

If you don't understand anything, feel free to ask for more
Good luck,
Ajith


Open Group Certified Distinguished IT Architect. Open Group Certified Master IT Architect. Sun Certified Architect (SCEA).
Amit Punjwani
Ranch Hand

Joined: Jul 10, 2000
Posts: 50
Thanx a lot Ajith that really helped
 
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