1.InputStream input = ClassLoader.getSystemResourceAsStream(fileName); 
InputStream input = XClass.class.getResourceAsStream(/fileName);
此時(shí)該文件在工程class目錄下,前面的會(huì)出問題

2.InputStream input = XClass.class.getResourceAsStream(fileName);
此時(shí)該文件和XClass在相同的目錄下


3.InputStream input  = new FileInputStream(new File(path,fileName));
此時(shí)該文件在path下