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Deleting Characters

Allen Thomas

Joined: Jul 02, 2002
Posts: 29
Would anyone know how to check for special characters (excluding some of the characters) in a String? For example: The String I am parsing is 1. MAINT & SVC*-7?8 and I want to find all the characters that I want to delete (see code below) and not have to right a huge case statement. Is there any already made java method that would check for special characters? So the sample string I want to keep the '.' and the '?'.
Keep in mind that the string could also contain many other characters that are accepted and not accepted.
Here is my code:

Thanks for your help.
[ August 15, 2002: Message edited by: Jim Yingst ]
Jim Yingst

Joined: Jan 30, 2000
Posts: 18671
Well, I guess it really depends what you mean by "special". The Character class has some methods you might find useful, like isLetter(), isNumber(), etc - using these may be shorter than listing all the letters/numbers/whatever. Or for a much more powerful and flexible toolset, check out the java.util.regex package. You can probably find a whole different way to approach the problem there.
If you do get stuck writing a case statement, it needn't be that bad. You've already got a fair amount of needless duplication in your code. For example if two different characters are processed the same way, you don't need to make separate case blocks for them - you can put them together, like # and & below:

Also, I'm guessing deleteCharacter is going to be a horribly inefficient method that creates a whole new String every time you want to delete a character. A smoother approach might be to create a StringBuffer. Instead of deleteing certain characters, you write your method to write all the other characters to the buffer. Then when you're done, use toString() to extract the boffer contents:

I have no idea what you're trying to do with the indexes, so I left them alone. But I suspect you're going to cause an infinite loop if you're not careful, so consider what you want to do here carefully. Good luck...
[ August 20, 2002: Message edited by: Jim Yingst ]

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John Dale
Ranch Hand

Joined: Feb 22, 2001
Posts: 399
Is this what you want done?
Allen Thomas

Joined: Jul 02, 2002
Posts: 29
Jim and John
Thank you so much for your great advice and help. I implemented both of your techniques in some capacity.
I agree. Here's the link:
subject: Deleting Characters