在生成的jar中打包所需的库正在加载属性文件，但提取所需的库未在加载属性文件

Question

（在生成的jar中打包所需的库）正在将我的属性文件加载到类路径中，但是（将所需的库提取到生成的jar中）却没有加载它。能否请我知道在提取时将属性文件加载到类路径中的正确方法（将所需的库提取到生成的jar中） 我的项目结构的PFB代码。project structure in STS IDE

public class ExcelReaderWithThread 
{

     static String timeStamp = new SimpleDateFormat("MM_dd_HH_mm").format(new java.util.Date());
     private static String Log_output;

     public static void main(String[] args) throws IOException, Exception 
     {

            int i=0,total_row_count=0;

        InputStream  in = ExcelReaderWithThread.class.getClassLoader().getResourceAsStream("app.properties");

        Properties prop = new Properties();
        prop.load(in);

            prop.getProperty("Source_File");
            prop.getProperty("Output_log_path");
            prop.getProperty("Threads");
            String t=prop.getProperty("Threads");
            int threads = Integer.parseInt(t);
            ExecutorService executor = Executors.newFixedThreadPool(threads);

            String Source_File =prop.getProperty("Source_File");
            String Output_path =prop.getProperty("Output_Path");
            String Output_fileName =prop.getProperty("Output_FileName");

            String log_name_1="output.csv";
            String log_name_2="Details.log";

            String Log_output_1= Output_path+timeStamp+"_"+log_name_1;
            String Log_output_2= Output_path+timeStamp+"_"+log_name_2;


            PrintStream logfile_1 = new PrintStream(new File(Log_output_1));
            PrintStream logfile_2= new PrintStream(new File(Log_output_2));

            Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
            long startTime = System.currentTimeMillis();
            File dir = new File(Source_File);
            File[] files = dir.listFiles();
            for (File file : files) 
            {
                i++;
                Runnable worker= new Writer(file);
                executor.execute(worker);
                logfile_2.println(file);
                System.setOut(logfile_2);



            }
            executor.shutdown();

            long stopTime = System.currentTimeMillis();
            System.out.print("Total number of file:"+i);
            System.setOut(logfile_1);

        }

}
class Writer implements Runnable
{


    File source;
    public Writer(File source) throws Exception 
    {
        this.source = source;



    }

    @Override
    public void run() 
    {
        try 
        {
            String content =  readFromFile(source.getAbsolutePath());
        } 

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

    static synchronized String readFromFile(String filename) throws Exception
    {
        String timeStamp = new SimpleDateFormat("MM_dd_HH_mm").format(new java.util.Date());


         String file_name = null;
         int  nu=0, total_row_count=0,count=0;
         StringBuilder sb = new StringBuilder();
         StringBuffer content = new StringBuffer();

        try 
        {
            Thread t1 = Thread.currentThread();
            File file= new File(filename);
            file.setWritable(true);
            FileInputStream inputStream = new FileInputStream(new File(filename));
            Workbook workbook = new XSSFWorkbook(inputStream);
            workbook.close();
            Sheet sheet = workbook.getSheetAt(0);
            nu= sheet.getLastRowNum();
            total_row_count += nu;
            file_name=file.getName();
            sb.append(file_name);
            sb.append(',');
            sb.append(nu);
            sb.append('\n');
            System.out.println(file_name+","+nu);



          } 

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


    return content.toString(); 


    }
}