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Using Runtime.getRuntime to run java

cardwell cupp
Ranch Hand

Joined: Aug 16, 2001
Posts: 66
I am using
Runtime.getRuntime.exec("javac " + path + file)
to compile a java works just fine.
Then when I use the same code to run it,
Runtime.getRuntime.exec("java " + path + class)
it comes back with a NoClassDeff error. Doesn't that usually mean that the classpath is not set correctly? But if I can do it with javac then why not java?
Cindy Glass
"The Hood"

Joined: Sep 29, 2000
Posts: 8521
Is the JVM putting the output class file in the classpath?

"JavaRanch, where the deer and the Certified play" - David O'Meara
Jim Yingst

Joined: Jan 30, 2000
Posts: 18671
My guess: use the -d option of javac to make javac create the class files in appropriate directories for their packages. E.g. if has a class Test in package mypkg, then
<pre>javac -d classdir</pre>
will create the file in classdir/mypkg/Test.class. I've never figured out why this isn't automatic, but you need to specify the option.

"I'm not back." - Bill Harding, Twister
I agree. Here's the link:
subject: Using Runtime.getRuntime to run java
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