The above lines mean whenever you want to use any class that is in any package, you have to use its fully qualified name, means name with package.
You can do it in different styles:
1) Using import statement to import package, and use only class name in given class, as package name is available all over in given class.
2) If you run on command line, then you have to use fully qualified name as on command line there is no import statement for your relief.
suppose
Suppose I put this file in F:/ drive
//for compilation
F:\>javac -d . JamesTharakan.java
//for running
F:\>java javaranch.saloon.scjp.james.JamesTharakan
Hi I am James
I cannot use this :
F:\>cd javaranch/saloon/scjp/james
F:\javaranch\saloon\scjp\james>java JamesTharakan
I cannot do this also:
F:\>java -cp javaranch/saloon/scjp/james JamesTharakan
You understand what I am saying, you have to use fully qualified name of that class, that I used in first example.