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== operator

 
budsy remo
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Hi again,

I know that the "==" operator chacks for two memory references being equal .
Now in the case of Strings if i make a String object as:


Then a String object would be created and a string literal will be placed in the memory pool .
Now if i create another String object as :


Now if a match is found in the pool then it's reference is directed to that literal in the memory pool.

Now my question is that why would something like this would hold false:

 
Campbell Ritchie
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I think we have an article on the Ranch, and there are lots of old threads, like this one, which has a link in the second post to that article. If that helps, all well; if it doesn't help, ask again
 
budsy remo
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i saw the thread but the problem is that it is returning false and not true .

String s = new String("ranch");
String s1 = new String("ranch") ;
System.out.printf(s==s1)

or something like

out.println(s=="ranch");

it should return true but it returns false

 
Henry Wong
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budsy remo wrote:i saw the thread but the problem is that it is returning false and not true .

String s = new String("ranch");
String s1 = new String("ranch") ;
System.out.printf(s==s1)

or something like

out.println(s=="ranch");

it should return true but it returns false



In the first case, you explicitly created two new strings. The JVM will honor that request, so you get two objects.

In the second case, you explicitly created a new string (actually one that you created earlier). The JVM will honor that request, so it should be different than the one created earlier for the string literals.

Henry
 
Campbell Ritchie
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I have found the article from the old thread I quoted: here it is It has an example very similar to yours in.
 
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