java method to get file extensions summary [regex and string interception]
- 2020-05-30 20:04:06
- OfStack
This article illustrates how java gets file extensions. I will share it with you for your reference as follows:
Problem description: there is 1 String type :String imageName = "zy.jpg "; How do I intercept the trailing name after "."?
Solution 1: use regular expressions
package csdnTest;
import java.util.regex.*;
public class CSDNTest
{
public static void main(String[] ss)
{
String s="abc.jpg";
//String regex=".+?//.(.+)"; That's fine, but I don't think it's as precise as that
String regex=".+?//.([a-zA-z]+)";
Pattern pt=Pattern.compile(regex);
Matcher mt=pt.matcher(s);
if(mt.find())
{
System.out.println(mt.group(1));
}
}
}
Solution 2:
System.out.println(imageName.substring(imageName.lastIndexOf('.')+1));
or
String FileType=imageName.substring(imageName.lastIndexOf('.')+1,imageName.length());
PS: here are two more handy regular expression tools for you to use:
JavaScript regular expression online testing tool:
http://tools.ofstack.com/regex/javascript
Online regular expression generation tool:
http://tools.ofstack.com/regex/create_reg
I hope this article is helpful for you to design java program.