的Java - 运行JAR拒绝加载文件在同一目录

Question

快速之一。我试图部署一个程序，它在以下代码中生效。我想读取一个名为，properties的属性文件。

Properties props = new Properties(); 
InputStream is; 
// First try - loading from the current directory 
try { 
    File f = new File("properties"); 
    is = new FileInputStream(f); 
} catch (FileNotFoundException fnfe) { 
    fnfe.printStackTrace(System.err); 
    is = null; 
} 
try { 
    if (is == null) { 
     // Try loading from classpath 
     is = getClass().getResourceAsStream("properties"); 
    } 
    //Load properties from the file (if found), else crash and burn. 
    props.load(is); 
} catch (IOException e) { 
    e.printStackTrace(System.err); 
} 

当我通过Netbeans运行程序时，一切顺利。

当我单独运行JAR时，虽然有，但我得到两个例外。

java.io.FileNotFoundException: properties (The system cannot find the file specified) 
     at java.io.FileInputStream.open(Native Method) 
     at java.io.FileInputStream.<init>(Unknown Source) 
     . 
     . 
     .   
Exception in Application start method 
Exception in Application stop method 
java.lang.reflect.InvocationTargetException 
     . 
     . 
     . 
     (exception during props.load(is) because is == null) 

我从“dist”文件夹运行文件。我已经尝试将属性文件放在jar文件夹内，没有结果。通常，properties文件位于根项目文件夹中。

任何想法？

Answer 1

你读文件作为资源（getResourceAsStream("properties");）。所以它必须在类路径中。也许在jar或直接添加到类路径的目录中。

坛子是一个zip文件，这样就可以用7zip的打开它，例如添加属性文件的罐子根级别，然后重试。

Answer 2

多亏了意见，我建立了基于罐子的当前运行目录的绝对路径生成。道具给你，伙计们。

private String relativizer(String file) { 
    URL url = RobotikosAnomologitos.class.getProtectionDomain().getCodeSource().getLocation(); 
    String urlString = url.toString(); 
    int firstSlash = urlString.indexOf("/"); 
    int targetSlash = urlString.lastIndexOf("/", urlString.length() - 2) + 1; 

    return urlString.substring(firstSlash, targetSlash) + file; 
} 

所以我的新文件阅读结构为：

 Properties props = new Properties(); 
     InputStream is; 
     // First try - loading from the current directory 
     try { 
      File f = new File("properties"); 
      is = new FileInputStream(f); 
     } catch (FileNotFoundException fnfe) { 
      fnfe.printStackTrace(System.err); 
      is = null; 
     } 
     try { 
      if (is == null) { 
       // Try loading from classpath 
       String pathToProps = relativizer("properties");  
       is = new FileInputStream(new File(pathToProps)); 
       //is = getClass().getResourceAsStream(pathToProps); 
      } 
      //Load properties from the file (if found), else crash and burn. 
      props.load(is); 
     } catch (IOException e) { 
      e.printStackTrace(System.err); 
     } 
     // Finally parse the properties. 
     //code here, bla bla