How to run a class from a jar with from command-line with classpath specified

问题

I am trying to run a class from a JAR. This class is NOT the only main class in this jar. Also, it requires number of other jar files, which I have kept in the same directory as this Jar. The commands I have tried are as follows:

(mydir is the directory in which all of my jars are located, using Windows platform)

mysql-connector-java-5.1.13-bin.jar is needed for myProjImport.jar to run and com.mycomp.myProj.importer.csv.TestImporter is the class i am trying to run. "C:\Documents and Settings\user\workspace\myProjImport\src\conf\datasource.properties" and "C:\temp\apollo_claims_test.txt" are the command line arguments required by the class TestImporter Here is what I have tried:

mydir>java -cp C:\temp\test_myProj\mysql-connector-java-5.1.13-bin.jar;. myProjImport.jar com.mycomp.myProj.importer.csv.TestImporter "C:\Documents and Settings\user\workspace\myProjImport\src\conf\datasource.properties" "C:\temp\apollo_claims_test.txt"

And here is the error:

Exception in thread "main" java.lang.NoClassDefFoundError: myProjImport/jar
Caused by: java.lang.ClassNotFoundException: myProjImport.jar
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: myProjImport.jar.  Program will exit.

Can someone please tell me what exact command should I run?

回答1:

try:

java -cp C:\temp\test_myProj\mysql-connector-java-5.1.13-bin.jar;myProjImport.jar com.mycomp.myProj.importer.csv.TestImporter "C:\Documents and Settings\user\workspace\myProjImport\src\conf\datasource.properties" "C:\temp\apollo_claims_test.txt"

provided your running this from the same direcotry as myProjImport.jar

回答2:

When -jar option is specified, any other class path options are ignored. So this won't work:

java -jar MyJar.jar -classpath foo.jar

But if you place foo.jar name into META-INF/manifest.mf within MyJar.jar:

Class-Path: foo.jar

Then the foo.jar will be searched on the same level as MyJar.jar, i.e. in the same directory.

Sometimes I just unpack all dependent JARs and pack their content into MyJar.jar. Fewer dependencies this way.

来源：https://stackoverflow.com/questions/5891343/how-to-run-a-class-from-a-jar-with-from-command-line-with-classpath-specified

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java

jar

classpath

executable-jar

noclassdeffounderror