About Java's file.separator

The path separators under windows are not the same as the path separators under Linux, and when you use absolute paths directly, cross-platform bursts out "No such file or diretory" exceptions.

For example, to create a test.txt file under the temp directory, which should be written under Windows:
File File1 = new file ("C:\tmp\test.txt");
Under Linux, this is the case:
File File2 = new file ("/tmp/test.txt");

If you want to consider cross-platform, it's best to write this:
File MyFile = new file ("C:" + file.separator + "tmp" + file.separator, "test.txt");

The file class has several static fields similar to separator, which are system-related and should be used as much as possible when programming.

Separatorchar

public static final Char Separatorchar

The system-related default name delimiter. This field is initialized to the first character that contains the system attribute File.separator value. On a UNIX system, the value of this field is '/'; on a Microsoft Windows system, it is ' \ '.

Separator

public static final String separator

The system-related default name delimiter, which is represented as a string for convenience. This string contains only one character, that is, Separatorchar.

Pathseparatorchar

public static final Char Pathseparatorchar

The system-related path delimiter. This field is initially the first character that contains the system attribute Path.separator value. This character is used to separate the file names in a sequence of files given as a list of paths. On a UNIX system, this field is ': '; on a Microsoft Windows system, it is '; '.

PathSeparator

public static final String PathSeparator

The system-related path delimiter, for convenience, is represented as a string. This string contains only one character, that is, Pathseparatorchar.

About Java's file.separator