Java File Extension Name Extract getFileExtension(File file)

Description

get File Extension

License

Open Source License

Declaration

public static String getFileExtension(File file) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.io.File;

public class Main {
    public static String getFileExtension(File file) {
        return getFileExtension(file.getPath());
    }//ww  w  .j  a v a 2  s  .  c o m

    public static String getFileExtension(String path) {
        int dot = indexOfDot(path);
        if (dot < 0) {
            return null;
        } else {
            return path.substring(dot + 1);
        }
    }

    private static int indexOfDot(String path) {
        int baseNameStart = path.lastIndexOf(File.separatorChar);
        if (baseNameStart < 0) {
            baseNameStart = 0;
        } else {
            ++baseNameStart;
        }

        int dot = -1;

        int pos = path.length();
        while ((pos = path.lastIndexOf('.', pos - 1)) > baseNameStart) {
            dot = pos;
        }

        return dot;
    }
}

Related

1. extractFileExtension(String path)
2. extractFileExtensionFromPath(String path)
3. getFileExtension(File f)
4. getFileExtension(File file)
5. getFileExtension(File file)
6. getFileExtension(File file)
7. getFileExtension(File file)
8. getFileExtension(File file)
9. getFileExtension(File file)