Error with Javac (class version error)

[Ja vardhan]

Hi,
am getting the following error when using 'ant compile' command:

java.lang.UnsupportedClassVersionError: com/sun/tools/javac/Main (Unsupported major.minor version 48.0).

whats this major.minor? whats this version 48.0??

I thought problem with PATH settings and pointin to two differant JRE versions. I checked PATH and CLASSPATH, they are pretty good.

Again, I had set the classpath in build file like:
<javac srcdir="src" destdir="build/classes" debug="on">
<classpath>
<fileset dir="C:\j2sdk1.4.0_03\lib" >
<include name="**/*.jar" />
</fileset>
</classpath>
</javac>
Now alos its not working.

Plsssssss clear me whats this major/minor and 48.0, what I need to resolve this??
Thanks.

[Carol Enderlin]

Perhaps running ant with -v will help.

48.0 refers to classes compiled - 1.4
49.0 refers to classes compiled - 1.5 aka 5.0

So, if you're getting an error that 48.0 isn't supported it sounds like an earlier version complaining (1.3 or earlier).

Are you including all the jars in jdk/lib directory in your classpath for a particular reason? That isn't usually necessary.

[Debashis Mukherjee]

if included "tools.jar" in CLASSPATH hope it is from the same java of JAVA_HOME, PATH.
ex. for 1.4
C:\j2sdk1.4.2_04\lib\tools.jar - CLASSPATH
C:\j2sdk1.4.2_04\bin - PATH
C:\j2sdk1.4.2_04 - JAVA_HOME

[Tim Holloway]

Ant or no ant, you don't/shouldn't include jars from a JAVA_HOME/lib directory explicitly to javac. They come in automagically.

I think that you are referring to the libs from a different version of Java than the one that's being used by your compiler, but it may be that Java is annoyed because you're disrupting the normal classpath rules and thereby getting hit by the classloader.