if no expanded-name, how to get file type(image/audio or video) by java

Question

if no expanded-name, how to get file type(image/audio or video) by java?

I want to write a function like this:

String getFileType(String filePath){
   // TODO:...
   return type;
}

Answer 1

Use the following code to get the extension of the file:-

public String getFileType(String fileName) {
        String extension = "";
        String extensionNew = "";
        int index = fileName.lastIndexOf(".");

        if (index > 0) {

            extension = fileName.substring(index + 1);
            extensionNew = fileName.substring(index); 
        }

        System.out.println("File extension is: " + extension);
        System.out.println("File extension new  is: " + extensionNew);
        return extensionNew;

    }

Otherwise, Apache Common IO is very popular API for file manipulations. Use the following link to download the jar. http://www.java2s.com/Code/Jar/c/Downloadcommonsio24jar.htm Download those jars, and finish it simple as follows:-

import org.apache.commons.io.FilenameUtils;

public class FileExtensionNew {

    public static void main(String[] args) {

        String extension = "";
        String extension2 = "";

        try {

            extension = FilenameUtils.getExtension("Hello.java");              // return ---> "java"
            extension2 = FilenameUtils.getExtension("home/java/Test.jar");    // return ---> "jar"

        } catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("File extension is: " + extension);
        System.out.println("File extension  is: " + extension2);
    }
} 

Hope, it will help you. Thanks!