Getting list of files in root directory

Question

I have seen many forum talking somewhat on this subject but I always see them using c: (for windows) as the example directory. I need to write this so that I can go to a Unix directory.
Example:
I want to go to the root directory from where I am....I would use runtime.exec(), right? But does the runtime actually go to that directory or just run the exec?
If there was a "name" such as c: in unix like windows it would be easier. But, I can not just say the name of the directory is / to get in there and check out the files. So, really what I want to do is if someone is not in the particular directory I want to be able to go to the root directory and check files there, then go to another directory and check the files there, etc.
I have a hard time explaining things so hopefully someone will get me.
Thanks.

Answer 1

But the trouble I am running in to is that I want the
root directory in Unix, which would be /. I can not
not just put that as the directory, can i?You can if you spell it out:
/export/home/thefunnyrootename
... or use:
String sysprop = System.getProperty("whatever property");
File f = new File(sysprop);... To determine which you want, SDK v1.3.1 docs for System.getProperty():
getProperties
public static Properties getProperties()
    Determines the current system properties.
    First, if there is a security manager, its checkPropertiesAccess
method is called with no arguments. This may result in a security
exception.
    The current set of system properties for use by the
getProperty(String) method is returned as a Properties object.
If there is no current set of system properties, a set of system
properties is first created and initialized. This set of system
properties always includes values for the following keys:
    Key Description of Associated Value
    java.version Java Runtime Environment version
    java.vendor Java Runtime Environment vendor
    java.vendor.url Java vendor URL
    java.home Java installation directory
    java.vm.specification.version Java Virtual Machine specification version
    java.vm.specification.vendor Java Virtual Machine specification vendor
    java.vm.specification.name Java Virtual Machine specification name
    java.vm.version Java Virtual Machine implementation version
    java.vm.vendor Java Virtual Machine implementation vendor
    java.vm.name Java Virtual Machine implementation name
    java.specification.version Java Runtime Environment specification version
    java.specification.vendor Java Runtime Environment specification vendor
    java.specification.name Java Runtime Environment specification name
    java.class.version Java class format version number
    java.class.path Java class path
    java.ext.dirs Path of extension directory or directories
    os.name Operating system name
    os.arch Operating system architecture
    os.version Operating system version
    file.separator File separator ("/" on UNIX)
    path.separator Path separator (":" on UNIX)
    line.separator Line separator ("\n" on UNIX)
    user.name User's account name
    user.home User's home directory
    user.dir User's current working directory
Note that even if the security manager does not permit the getProperties
operation, it may choose to permit the getProperty(String) operation.
Returns:
the system propertiesThrows:
SecurityException - if a security manager exists and its
checkPropertiesAccess method doesn't allow access to the system
properties.See Also:
setProperties(java.util.Properties), SecurityException,
SecurityManager.checkPropertiesAccess(), Properties~Bill