Running programs from the command line

When invoking jMetal programs from the command line I always have use de java command. My development machine is a MacBook, but I also have access to a Linux one and to a virtual machine with Windows 8.1 (with GitBash installed) to make some tests.

In the case of jMetal 5.0, I set first the CLASSPATH environment variable:

export CLASSPATH=jmetal-core/target/classes/:jmetal-exec/target/classes/:jmetal-problem/target/classes/:jmetal-algorithm/target/classes/

and then I write something like this:

java org.uma.jmetal.runner.multiobjective.SMPSORunner org.uma.jmetal.problem.multiobjective.Golinski

However, sometimes I have got runtime errors about missing libraries:

java org.uma.jmetal.qualityIndicator.CommandLineIndicatorRunner ALL jmetal-problem/src/test/resources/pareto_fronts/Kursawe.pf FUN.tsv 

The fronts are NOT NORMALIZED before computing the indicators
EP: 2799.499447785977
HV: 0.0
GD: 381.1994951105707
IGD: 102.76887872890298
IGD+: 3038.206812393222
SPREAD: 0.910670889364176
GSPREAD: 0.9045628203376009
R2: 1464.6004537062856
ER: 1.0
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/lang3/tuple/Pair
    at org.uma.jmetal.qualityIndicator.CommandLineIndicatorRunner.calculateAndPrintIndicators(CommandLineIndicatorRunner.java:131)
    at org.uma.jmetal.qualityIndicator.CommandLineIndicatorRunner.main(CommandLineIndicatorRunner.java:48)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang3.tuple.Pair
    at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 2 more

Any ideas about the reason of these kinds of errors? My concern is why a particular class (Pair) is not found while there are many other dependences.

I’ve tried the alternative of using mvn:

mvn -pl jmetal-exec exec:java -Dexec.mainClass="org.uma.jmetal.qualityIndicator.CommandLineIndicatorRunner" -Dexec.args="ALL jmetal-problem/src/test/resources/pareto_fronts/Kursawe.pf FUN.tsv"

and this works ok, but it is a very cumbersome way of running a program.

[matthieu-vergne]

Hum… taste for using export or -cp, but not for the content of the classpath: you fail in testing the right stuff with your current classpath. The point is that we would like here to ensure that using a single JAR containing everything works. With your classpath, you cannot ensure that, because you include all the JARs, but whether you use the usual JARs or the ones having all the dependencies, it is the same.

Normally, if you have only the exec JAR, it should work, but if you have only the core one, it should not, because you have no algorithm there. This is important to know, and final users should get the right JAR based on their needs: developers of new algorithms need only the core JAR, people wanting to use implemented algorithms need the algorithm JAR, people who want to try jMetal with its own features need the exec JAR, etc. Of course having the most complete one is OK for everyone (and it should be the one to provide on the website), then people have to search for the best one if they want to reduce its size.

Using export is a good idea when you plan to do a lot of commands with the exactly same classpath, but it becomes a trap when you just aggregate everything in your classpath to use many commands which should use different classpaths, because the missing stuff in one is provided by another, so no exception is thrown while it should. For a final user, it should be always the same, but in our case, we have to pay attention to not hide the problems like that. {'^_^}

[matthieu-vergne]

Thanks. I never touch my classpath, so I used an explicit mention of the JAR:

java -cp jmetal-exec/target/jmetal-exec-5.0-Beta-35-SNAPSHOT-jar-with-dependencies.jar org.uma.jmetal.qualityIndicator.CommandLineIndicatorRunner ALL jmetal-problem/src/test/resources/pareto_fronts/ZDT1.pf jmetal-exec/FUN.tsv 

and it works too:

The fronts are NOT NORMALIZED before computing the indicators
EP: 0.012395707711604587
HV: 0.6596071215396984
GD: 2.5877015814296586E-4
IGD: 1.818754655873446E-4
IGD+: 0.0037047948004080974
SPREAD: 0.3288337056716771
GSPREAD: 0.3455973515141629
R2: 0.13185496556199539
ER: 1.0
SC(refPF, front): 0.92
SC(front, refPF): 0.0