在Ubuntu命令行上Java的库安装位置

Question

I'm trying to get the Charva tutorial to work, but I don't think I'm installing it correctly. I added the .jar files to /jre/lib/ext, but I get this error when I try to run the tutorial file:

Exception in thread "main" java.lang.NoClassDefFoundError: Tutorial (wrong name: tutorial/java/Tutorial)
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482)

Am I supposed to be running something else when I compile or am I installing the library the wrong way?

Answer 1

I suggest you build and run your program in your IDE.

Once you have a working program you can build a JAR and when you specify it on the command line with

java -cp {path-to-my-jar}.jar mypackage.MyClass

you can put the JAR where ever you like.

Answer 2

You can add the .jar files to the classpath using:

java -cp "Charva.jar" main.Class

If you need to add multiple jars, or you want it to be better structured in folders, put the jars under lib which is the common thing to do, and use:

java -cp "lib/*.jar" main.Class

If you're using and IDE, tag the question with the specific IDE to get specific instructions for your IDE.