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sorting by a primitive int field

 
saima kanwal
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I am trying to sort my array list using comparator. please review my code and solve my problem. I want to sort my array list by int type isbn number of book. My code is as follows:




And it does not compile because I am using the compare to method with int. How am i going to compare int (primitive)? please modify my code.

saima.
 
Christophe Verré
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Hint: The Integer class is comparable
 
Ankit Garg
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In the above statement, isbn is a primitive so you can't call compareTo method on it. But since it is a primitive, you can use comparison operator on it. So if you see the source code of Integer class, the compareTo method is implemented like this

You can implement your compareTo method in the same way too. To make it even simpler, you can just write
 
I agree. Here's the link: http://aspose.com/file-tools
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