Some methods in other classes also return File objects, most notably the java.awt.FileDialog methods, which I will discuss shortly.
The File objects returned by these methods should conform to the conventions of the host operating system. For instance, the path separator character will be : on a Mac and on Windows.

public class File extends Object
implements Serializable, Comparable<File>	

The first name in an abstract pathname may be a directory name or, in the case of Microsoft Windows UNC pathnames, a hostname. Each subsequent name in an abstract pathname denotes a directory. The last name may denote either a directory or a file. The empty abstract pathname has no prefix and an empty name sequence. The conversion of a pathname string to or from an abstract pathname is inherently system-dependent. When an abstract pathname is converted into a pathname string, each name is separated from the next by a single copy of the default separator character.
The default name-separator character is defined by the system property file.separator, and is made available in the public static fields separator and separatorChar of this class. When a pathname string is converted into an abstract pathname, the names within it may be separated by the default name-separator character or by any other name-separator character that is supported by the underlying system.
A pathname, whether abstract or in string form, may be either absolute or relative. An absolute pathname is complete in that no other information is required in order to locate the file that it denotes.
A relative pathname, in contrast, must be interpreted in terms of information taken from some other pathname. By default the classes in the java.io package always resolve relative pathnames against the current user directory.
This directory is named by the system property user.dir, and is typically the directory in which the Java virtual machine was invoked.