StringUtils.isNumeric is undefined method [duplicate]

Question

I have imported that library:

import org.apache.commons.codec.binary.StringUtils;

And tried to use some of methods, but failed:

StringUtils.isNumeric("2398sdf");

IDE keep saying me that, method is undefined. What is wrong here?

Well what makes you think it should be present? I can't see it in the documentation: commons.apache.org/proper/commons-codec/apidocs/org/apache/… — Jon Skeet
– Jon Skeet, Commented Mar 1, 2016 at 9:05
Did you download the jar with StringUtils ? .. See stackoverflow.com/questions/8660151/… — DTH
– DTH, Commented Mar 1, 2016 at 10:55

Jon Skeet · Accepted Answer · 2016-03-01 09:09:33Z

3

You're using the wrong StringUtils class. You're importing org.apache.commons.codec.binary.StringUtils, but it looks like you want org.apache.commons.lang.StringUtils or org.apache.commons.lang3.StringUtils. The first of these doesn't have an isNumeric method, whereas both of the lang-based ones do.

Obviously this means you'll need the "commons lang" library to be in your classpath. (Which class you import will depend on which version you use.)

answered Mar 1, 2016 at 9:06

Jon Skeet

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2 Comments

Heck, you can have this answer :(

Eclipse confused me, thank you for the answer @JonSkeet)

Robert Kock · Accepted Answer · 2016-03-01 09:07:54Z

3

The StringUtils.isNumeric method is defined in the package org.apache.commons.lang3 and not in the one you specified.

answered Mar 1, 2016 at 9:07

Robert Kock

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