1.InputStream input = ClassLoader.getSystemResourceAsStream(fileName);
InputStream input = XClass.class.getResourceAsStream(/fileName);
此時該文件在工程class目錄下,前面的會出問題
2.InputStream input = XClass.class.getResourceAsStream(fileName);
此時該文件和XClass在相同的目錄下
3.InputStream input = new FileInputStream(new File(path,fileName));
此時該文件在path下