CODEWITHSUNDEEP
javastringinteger
user793623
user793623

Reputation:

Integer vs. String decision making in Java

I'm working on a program where user input is an array of mixed Strings and Integers. For Example:

dog 10 23 cat frog 22 elephant

I'm supposed to sort this array without changing the type of each index. So the output will be;

cat 10 22 dog elephant 23 frog

After reading the line from the console, I'm using a string tokenizer to go through each element. After that I'm trying to parseInt and if it throws an exception, I'm assuming that it is a string, otherwise it is an Integer. Is there a better way to figure out if a token is numerical or not?

Thank you.

Upvotes: 4

Views: 389

Answers (3)

joran
joran

Reputation: 2883

You can for example use 'StringUtils.isNumeric' to detect if a string is numerical

http://commons.apache.org/lang/api-2.3/org/apache/commons/lang/StringUtils.html

The drawback is that you have to include a library.

Upvotes: 0

Gowtham
Gowtham

Reputation: 1475

Relying on exceptions for program logic is considered poor practice because exceptions are slow. Instead, you can use regular expressions.

Matcher numericalMatcher = Pattern.compile("^-?\\d+$").matcher(token);
if( numericalMatcher.matches() ) {
   // Token is a number
} else {
   // Token is not a number
}

See http://docs.oracle.com/javase/1.6.0/docs/api/java/util/regex/Pattern.html and http://docs.oracle.com/javase/1.6.0/docs/api/java/util/regex/Matcher.html

Upvotes: 6

dash1e
dash1e

Reputation: 7807

Using parseInt is not a bad idea.

Alternatively you can use a regular expression but I believe your choice is more practical and simple.

Upvotes: 3

Related Questions