set java classpath on linux

rotation · 11-26-2011, 01:09 PM

Code:

denislav@linux-kzpj:~/Desktop> echo $JAVA_HOME
/usr/bin/java
denislav@linux-kzpj:~/Desktop>

SecretCode · 11-26-2011, 01:33 PM

This is getting odd.

Is myfirstjavaprog.java on the same machine? What does it contain?

rotation · 11-26-2011, 01:38 PM

Code:

class myfirstjavaprog
{
        public static void main(String args[])
        {
           System.out.println("Hello World!");
        }
}

SecretCode · 11-26-2011, 01:46 PM

What is

Code:

javac -version

What happens if you recompile it:

Code:

javac myfirstjavaprog.java
java myfirstjavaprog

rotation · 11-26-2011, 01:51 PM

Code:

denislav@linux-kzpj:~/Desktop> javac -version
javac 1.7.0_01
denislav@linux-kzpj:~/Desktop>

Code:

denislav@linux-kzpj:~/Desktop> javac myfirstjavaprog.java

denislav@linux-kzpj:~/Desktop> 
denislav@linux-kzpj:~/Desktop> java myfirstjavaprog
Exception in thread "main" java.lang.UnsupportedClassVersionError: myfirstjavaprog : Unsupported major.minor version 51.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:637)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:277)
	at java.net.URLClassLoader.access$000(URLClassLoader.java:73)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:212)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:323)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:268)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:336)
Could not find the main class: myfirstjavaprog. Program will exit.

SecretCode · 11-26-2011, 02:17 PM

Quote:

Originally Posted by rotation

Code:

denislav@linux-kzpj:~/Desktop> javac -version
javac 1.7.0_01
denislav@linux-kzpj:~/Desktop>

There's your problem. You have 1.7 of javac and 1.6 of java. You'll need to downgrade the package that provides javac or upgrade your java runtime. Do you know how to do that?

rotation · 11-26-2011, 02:21 PM

No :-(

SecretCode · 11-26-2011, 02:28 PM

Can anyone else help? I know nothing about package management in openSUSE ...

rotation · 11-26-2011, 02:31 PM

Thank you for the information about java and javac!

rotation · 11-29-2011, 06:23 AM

Code:

denislav@linux-kzpj:~/Desktop> java -version
java version "1.6.0_0"
OpenJDK Runtime Environment (IcedTea6 1.6) (suse-5.9.4-i386)
OpenJDK Server VM (build 14.0-b16, mixed mode)
denislav@linux-kzpj:~/Desktop> javac -version
javac 1.6.0_29
denislav@linux-kzpj:~/Desktop>

I runned myfirstjavaprog. Thank you very much!