Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
//License from project: Apache License 

import java.io.File;

public class Main {
    public static String extension(String filename) {
        if (filename == null || filename.length() == 0) {
            return "";
        }
        // Ensure the last dot is after the last file separator
        int lastSep = filename.lastIndexOf(File.separatorChar);
        int lastDot;
        if (lastSep < 0) {
            lastDot = filename.lastIndexOf('.');
        } else {
            lastDot = filename.substring(lastSep + 1).lastIndexOf('.');
            if (lastDot >= 0) {
                lastDot += lastSep + 1;
            }
        }

        if (lastDot >= 0 && lastDot > lastSep) {
            return filename.substring(lastDot + 1).toLowerCase();
        }

        return "";
    }
}