Diferences between the java options -classpath and -Xbootclasspath

Question

I have created several jar files containing my own clases using the j2skd 1.4.0
I am not understand the diferences between the following options:
1) Copying this files into the path .../j2re1.4.0/lib/ext/
2) Using the java option -Xbootclasspath/a
3) Using the java option -classpath
Options 1 and 2 works fine for using the clases on my jar files but I don�t understand why the option 3 is not working.
About my clases:
a) All are contained on a package example cvm.util
b) The class files that refers to this uses the directive:
"import cmv.util;"
c) Non of them replaces any original java class
Any suggestions?

Answer 1

The following command:
java -cp c:\Work\java\Smartt\cvutil.jar;c:\Work\java\Smartt\stutil.jar -jar C:\work\java\smartt\STServer.jar SAPMOVS.STR PRE
Generates:
Exception in thread "main" java.lang.NoClassDefFoundError: cvm/st/ST
at STServer.<init>(STServer.java:66)
at STServer.main(STServer.java:56)
But if I replace the -cp option for -Xbootclasspath/a:
java -Xbootclasspath/a:c:\Work\java\Smartt\cvutil.jar;c:\Work\java\Smartt\stutil.jar -jar C:\work\java\smartt\STServer.jar SAPMOVS.STR PRE
It works fine!!
or if I copy the two jar files into the ../lib/ext path
Then it also works pefect!
Thanks in advance