How to proper set java in windows?

Question

I have installed java. I want work in cmd, so I write javac name_of_file.java. Javac was unrecognize, i must add path to java. I was searching of "javac" on computer. I was copy that adress and add to path.

Now, javac work, but when i write: java name_of_file I have got that comunicate:

 C:\Users\Naukowy>java version
Exception in thread "main" java.lang.NoClassDefFoundError: ver
 Caused by: java.lang.ClassNotFoundException: version
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown
    at java.lang.ClassLoader.loadClass(Unknown Source)
Could not find the main class: version.  Program will exit.

Next I wrote : java version And I have got the same message.

How can I make that will proper works?

 C:\Users\Naukowy\Desktop\plik xml>javac XSDValidate.java

C:\Users\Naukowy\Desktop\plik xml>java XSDValidate
Exception in thread "main" java.lang.UnsupportedClassVersionError: XSDValidate :
 Unsupported major.minor version 51.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClassCond(Unknown Source)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$000(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
 Could not find the main class: XSDValidate.  Program will exit.

C:\Users\Naukowy\Desktop\plik xml>

Is `version` the name of your class? – T.J. Crowder May 04 '14 at 09:28 — T.J. Crowder, May 04 '14 at 09:28

score 2 · Answer 1 · edited May 23 '17 at 10:26

2

I'm not sure what your problem exactly is, so I'll try to explain all possible problems that I see here ;):

Do you want to find out the Java version? Use

java -version.

Compared to that,

java version

tries to start a Java class called version, which doesn't exist obviously.

If you want to compile a .java file, use

javac file.java

That will result in a file.class class file to be created. To run that:

java file

Thanks to T.J. Crowder for the correction. Don't try java file.class, but use java file.

Update Your major/minor version issue is a totally different issue. See How to fix java.lang.UnsupportedClassVersionError: Unsupported major.minor version for more information.

edited May 23 '17 at 10:26

Community

1
1

answered May 04 '14 at 09:27

fjc

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I just do it yes? javac a.java java a And I have that comunicate what I wrote what can I do? Where I wrote I use java file.class? Where ? – user3164700 May 04 '14 at 09:41
Please give us your entire console input and output. I don't understand what exactly you are doing and where the problem is. – fjc May 04 '14 at 09:44
I add now what I do step by step – user3164700 May 04 '14 at 09:51
That's a completely different issue now. See my updated answer. – fjc May 04 '14 at 09:53

How to proper set java in windows?

1 Answers1