I am trying to compile my first JAVA file using command line (yes, I know the existence of IDEs).
My App.java sits inC:\Documents and Settings\
My jre is in C:\Program Files\Java\jre1.5.0_10\
But I get following error.
C:\Documents and Settings>javac App.java
'javac' is not recognized as an internal or external command,
operable program or batch file.
What has gone wrong?
Thanks.
ancino_man,
if you have the JDK (15 hours is a looooong time... I think I heard once that Sun will send you a copy on CD upon request) then make sure C:\Program Files\Java\jdk1.5*\ is in your path.
if you don't know how to do that confidently then google "change windows path"... I really really love google.
keith.
> The JDK comes with the JRE, so you may or may not have it already.
Saying it that way is a bit confusing: You can either download the JRE
or the JDK. If you just download the JRE you can only run compiled
programs; if you download the JDK, the JRE comes with it; as a matter
of fact you get *two* JREs: one with which you run programs and one
used by the JDK itself.
kind regards,
Jos
I have managed to compile App.java and App.class is present (verified with Windows Explorer. But when I run the command "java App.class", an error message was displayed (please see the following).
********** from the command prompt
C:\Program Files\Java\jdk1.6.0\bin>javac C:\App.java
C:\Program Files\Java\jdk1.6.0\bin>java App.class
Exception in thread "main" java.lang.NoClassDefFoundError: App/class
************************************
However, the same App.java run without any problems when loaded onto Eclipse SDK.
Can anyone enlighten?
Thanks.
The Java JVM doesn't look in the current working directory for classes by
default. It checks the 'classpath' which is a list of directories and .jar
files for .class files. You can specify this classpath on the command line:
java -classpath . YourApp
Note the dot '.' it represents your current working directory.
kind regards,
Jos
Thanks!
I am now able to run the bytecode but only when the .class resides in the same directory as the jdk. Before line 4, I physically moved App.class into
C:\Program Files\Java\jdk1.6.0\bin>
(see the following).
******** from command prompt
C:\Program Files\Java\jdk1.6.0>cd bin
C:\Program Files\Java\jdk1.6.0\bin>java c:\App
Exception in thread "main" java.lang.NoClassDefFoundError: c:\App
C:\Program Files\Java\jdk1.6.0\bin>java App
Hello World!
C:\Program Files\Java\jdk1.6.0\bin>
************************************
After "Hello World!" is displayed on the screen, I moved the App.java back into c:\and issued the following command:
C:\Program Files\Java\jdk1.6.0\bin>java -classpath c:\
******* result from command prompt
:
:
-classpath <class search path of directories and zip/jar files>
A ; separated list of directories, JAR archives,
and ZIP archives to search for class files.
:
:
*************************************
How should I correct this?
Thanks.
