输入流为 null

Question

In a program I'm working on I have

String cwd;
String file_separator;

public ConfigLoader()
{
    cwd = get_cwd();
    file_separator = get_file_separator();

    try
    {
        Properties c = new Properties();

        InputStream in = this.getClass().getClassLoader().getResourceAsStream(cwd + 
            file_separator + "data" + file_separator + "configuration.properties");

        c.load(in);
    }
    except (Exception e) { e.printStackTrace(); }
}

public String get_file_separator()
{
    File f = new File("");
    return f.separator;
}

public String get_cwd()
{
    File cwd = new File("");
    return cwd.getAbsolutePath();
}

For some reason, though, c.load(in); causes a NullPointerException . The exception comes from in == NULL being true. I can't figure out why because

System.out.println(cwd + file_separator + "data" + file_separator +
    "configuration.properties");

prints

/users/labnet/st10/jjb127/workspace/Brewer-Client/data/configuration.properties

which is the location of the file I'm wanting to use.

Thoughts?

Answer 1

getResourceAsStream is meant to search for files on the classpath and not for accessing the local file system. You will have to use FileInputStream for this case.

InputStream in = new FileInputStream(cwd + 
    file_separator + "data" + file_separator + "configuration.properties");