Windows 7 - Umbenennen von Dateien mit Präfixen variabler Länge

@echo off & setlocal enabledelayedexpansion
for /f "delims=- tokens=1,*" %%s in ('dir /b /a-d') do (  
	set "var=%%t"  
	if defined var (echo ren "%%s-%%t" "%%t") else (echo ren "-%%s" "%%s")  
	)
pause

import java.io.File;

public class start {
	public static void main(String args) {
		
		if(args.length < 2){
			System.err.println("Not enough start parameters");  
			System.exit(1);
		}
		if(!new File(args[1]).isDirectory()){
			System.err.println(args[1]);
			System.err.println("Given path is no folder");  
			System.exit(1);	
		}
		String preafix = args;
		String filePath = args[1];
		
		File path = new File(filePath);
		File allFiles = path.listFiles();
		
		for(int i = 0;allFiles.length > i;i++) {
			if(allFiles[i].isFile()){
				//Dateien
				if(allFiles[i].getName().toString().contains(preafix)){
					
					if(!new File(allFiles[i].getParent() + System.getProperty("file.separator") + allFiles[i].getName().split("-", 2)[1]).exists()) {  
						System.out.println("Rename: " + allFiles[i].getName() + " -> " + allFiles[i].getName().split("-", 2)[1]);  
						allFiles[i].renameTo(new File(allFiles[i].getParent() + System.getProperty("file.separator") + allFiles[i].getName().split("-", 2)[1]));  
					} else {
						System.err.println("Duplicated filename: " + allFiles[i].getName() +" # " + allFiles[i].getName().split("-", 2)[1]);  
					}
					
				} else {
					System.out.println("Ignore: " + allFiles[i].getName());  
				}
				
			} else {
				//Ordner
			}
		}
	}

}

Rename: 34g9un-blarg30333.TXT -> blarg30333.TXT
Rename: uhbeuw-moepMoep12121.TXT -> moepMoep12121.TXT
Rename: uhqqw543Dbeuw-BLAAblaa123.TXT -> BLAAblaa123.TXT

Ignore: BLAAblaa123.TXT
Ignore: blarg30333.TXT
Ignore: moepMoep12121.TXT

Ignore: BLAAblaa123.TXT
Duplicated filename: check-BLAAblaa123.TXT # BLAAblaa123.TXT