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String == and equals() doubt

Shiva Mohan
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Joined: Jan 05, 2006
Posts: 479

I thought it would output false true.But it gave true

(i==j)---------I and j are references having same value but different object references.Then how come it will produce true.Please explain it for me.
Ryan McGuire
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Joined: Feb 18, 2005
Posts: 1025
The problem isn't with your understanding of == and equals(); it's a question of what you're printing out.

So let's say i and j are two different objects. That means that the condition in your first if would be false. Therefore you print the boolean value of i!=j, as opposed to the String "i!=j". Since i is NOT == j, the expression i!=j is true. That's what gets printed: "true".

You can collapse that first if/else with its two println() statements into just a single...

You have a similar problem with the second if. Let's say i="Ryan" and j="Shiva". The expression in the if will be false, so it goes to the else part. There it prints out the value of the expression !i.equals(j). Since i.equals(j) is false, NOT i.equals(j) is true. So "true" gets printed.

Just replace that whole if/then with...

[ March 29, 2006: Message edited by: Ryan McGuire ]
I agree. Here's the link:
subject: String == and equals() doubt