Java Compiler and JVM.

[dmjpro]

does it happen ....???? that if a .class generated in lower version JAVAC and then it going to run by upper version of JVM.

could any one tell me the dtls story of these two key terms??
plz help.

kind regards.
dmjpro.

[JosAH]

does it happen ....???? that if a .class generated in lower version JAVAC and then it going to run by upper version of JVM.

could any one tell me the dtls story of these two key terms??
plz help.

kind regards.
dmjpro.

Yep, code compiled with an older (earlier) version of javac runs on a newer (or
later version) jvm. The opposite is not true though.

kind regards,

Jos

[dmjpro]

plz tell me why??

is there any byte code specification mismatches or anything else????
plz help.

kind regards.
dmjpro.

[JosAH]

plz tell me why??

is there any byte code specification mismatches or anything else????
plz help.

kind regards.
dmjpro.

Nope, it's just a matter of newer classes that were not present in older releases
of the jre (the jvm plus the set of core classes). If your compiled code wants to
use those newer classes it can't run on an older jvm. The jvm explicitly checks
that when your class is loaded, whether or not your class does use newer
classes or not; the version number is out of sink (higher) than the number
supported by the jvm.

kind regards,

Jos

[dmjpro]

Now i seee ...... actually a JVM comes with some core classes.
right???

thanks a lot.
a confusion clearified.....
again thanks a lott.

kind regards.
dmjpro.