如何获得文件扩展名

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问题描述：  有一个String类型:String imageName = "zy.jpg"; 请问我如何截取"."后面的后辍名.

解法一：我的解法，使用正则表达式

package csdnTest;import java.util.regex.*;public class CSDNTest {public static void main(String[] ss){String s="abc.jpg";//String regex=".+?//.(.+)";这种写法也是可以的，但我认为没有后面的精确String regex=".+?//.([a-zA-z]+)";Pattern pt=Pattern.compile(regex);Matcher mt=pt.matcher(s);if(mt.find()){System.out.println(mt.group(1));}}}

解法二：

System.out.println(imageName.substring(imageName.lastIndexOf('.')+1));

 

或者

String FileType=imageName.substring(imageName.lastIndexOf('.')+1,imageName.length());

 

 

 

 

 

 

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