(b) Type in this command in the terminal window:
jar -umf x.mf app.jar
The “u” stands for update , the “m” for manifest , and the “f” for file . Since the
“m” precedes the “f”, the manifest file name, x.mf , precedes the file name,
app.jar . This command inserts into jar file app.jar the fact that method main
appears in class CMain .
You can insert the classes and the main-class manifest in one step using:
jar -cmf x.mf app.jar *.class
You can now email file app.jar to anyone, and they can run it on their com-
puter, whether it is a Unix, Macintosh, or Windows system, as long as their sys-
tem runs java. To execute the program, type this (include the extension .jar ):
java -jar app.jar
In some systems, you will be able to run the program by double-clicking the file.
If you want to see what is in jar file app.jar , then type this:
jar tvf app.jar
You can find out more about the jar command by typing the following and hit-
ting the enter/return key:
If you cannot execute any of the commands java , javac , jar , and javadoc ,
then you probably have not set your path correctly. We explain this for Windows
2000; older windows systems are similar.
Your system contains a variable that lists directories that have executable
files in them. Type path in a command-line window. A line will be printed that
contains path names separated by semicolons. For example, one path name may
There should be a path that looks something like this:
This is a directory called bin inside the directory where you installed the sdk. It
may be different on your computer. If such a path is not there, you have to add
it. Bring up the help in your Windows system, open the index, and look for path .
There, you will find instructions on appending another directory to variable
path . It may be something like the following, but read the instructions: