Use Operator == for String Comparison

Hi,
I would like to know more about the impact of using operator == in String Comparison.
From the reference I get, it state this :
"Operator (==) compares two object addresses to see whether it refers to the same object."
I've tested it with 2 codes as below :
Code 1:
          String Pass1 = "cosmo";
          String Pass2 = "cosmo";
if (Pass1==Pass2)
               System.out.println("1&2:same");
          else
               System.out.println("1&2:not same");
Output : 1&2:same
Code 2:
          String Pass3 = new String("cosmo");
          String Pass4 = new String("cosmo");
          if (Pass3==Pass4)
               System.out.println("3&4:same");
          else
               System.out.println("3&4:not same");
Output : 3&4:not same
Can anyone kindly explain why is the result so? If operator == compares the addresses, isn't it that the 1st code should also have the output :"1&2:not same".

Can anyone kindly explain why is the result so?It's an implementation artifact. Strings are pooled internally and because of that any String literal will be represented by exactly one object reference.
Knowledge of this shouldn't be utilized though. It's safer to follow the basic rule: Use == to compare object references and equals to compare object values, such as String literals.

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Revision: 18053
Revision: 18053
Author:   [email protected]
Date:     2010-10-07 03:27:37 -0700 (Thu, 07 Oct 2010)
Log Message:
BLZ-571: Use of wrong operator in string comparison in flex.messaging.VersionInfo.java
Updated the code to use the right operator.
Check-in Tests: PASS
QA: Yes
Ticket Links:
    http://bugs.adobe.com/jira/browse/BLZ-571
Modified Paths:
    blazeds/trunk/modules/core/src/flex/messaging/VersionInfo.java

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