1.截取不带后缀的文件名 String resourceName=resourceSearchBean.getFileName(); 
if(StringHelper.isNotEmpty(resourceName)&&resourceName.length()>0); 
{ 
int dot = resourceName.lastIndexOf('.'); 
if ((dot >-1) && (dot < (resourceName.length()))) { 
return resourceName.substring(0, dot); 
} 
} 
2.截取文件后缀名  
public static String getExtensionName(String filename) { 
if ((filename != null) && (filename.length() > 0)) { 
int dot = filename.lastIndexOf('.'); 
if ((dot >-1) && (dot < (filename.length() - 1))) { 
return filename.substring(dot + 1); 
} 
} 
return filename; 
}