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Amruth Puppala
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Joined: Jul 14, 2008
Posts: 295
In Scanner we have methods nextInt(), nextFloat().

What is the exact purpose of these methods we have next() method to use rite.

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Sagar Rohankar
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Joined: Feb 19, 2008
Posts: 2904

This methods actually works on Regular expression , If your input which you expect to be a series of integers, then you can scan them using nextInt() , which definitely returns only int and rest of input type is ignored , same for nextFloat(),


next() is kind of generics !, It can take any kind of input no matter , what you scan !

This topic helps you to understand this concept better !

Hope this Helps !
[ July 31, 2008: Message edited by: Sagar Rohankar ]

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Amruth Puppala
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Joined: Jul 14, 2008
Posts: 295

If My iput is "abc 2000 xyz 5000".

If I use nextInt() 1st, what happens can't it find directly 2000 instead of "abc"?

Becuase abc is a string so I thought I will retrun next int i.e 2000. But it is thowing exception.

Please expain me nit clear about nextInt().
[ August 01, 2008: Message edited by: Chintu sirivennela ]
Sumit Bisht
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Joined: Jul 02, 2008
Posts: 331

Well Chintu! you are not checking firstly for the occurrence of an int
Please use :
int i=scanner.nextInt();
If you simply use next(), it'll give you everything with space as a default delimiter
Ralph Jaus
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Joined: Apr 27, 2008
Posts: 342
nextInt() takes the next token and tries to convert it into an integer. If the token doesn't represent an int, an exception is thrown. Therefore, before using nextInt() you should apply hasNextInt(). This method checks whether the next token really represents an int.

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Amruth Puppala
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Joined: Jul 14, 2008
Posts: 295
Thanks for good response
I agree. Here's the link:
subject: Scanner
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