Added code to existing source file, compiled it, and class file shrunk

Another newbie here. Fortunately, my classpath is ok, so I'm able to compile a .java file.
I added one line of code (System.out.println) to write the value of a variable to a log. After compiling with javac, I noticed that the resulting [new] class file was smaller than the existing class file. I looked at each of the class files with Textpad. It's gibberish, but I quickly saw that a large block of code was missing in the new class file, even though the size of the source file had been increased.
There is a difference, however, between how the two class files were created. The existing class file was compiled (along with many others) by exporting an .EAR file from a development environment (WSAD) to the WebSphere Administrator Console. Conversely, I am now compiling the same source file with javac on my machine.
I suspect that this is the reason why I can add code to a .java file, compile it, and have the resulting class file actually lose code. Even if I am correct, I don't know what to do about it.
Does anyone have an idea?
Regards,
Daniel T.

Thank you both for your replies. I've read many posts over the past few months, and I know how important it is to provide as much info as possible, when asking a question here. That said, I have another tasty tidbit...
After replacing the existing (larger) class file with the new (smaller) class file, my application now produces this:
"*Error 500: LinkageError while defining class*..." [name of class]
*"...(Unsupported major.minor version 50.0) This is often caused by having a class defined at multiple locations within the classloader hierarchy. Other potential causes include compiling against an older or newer version of the class that has an incompatible method signature. Dumping the current context classloader hierarchy: ==> indicates defining classloader ==>[0] com.ibm.ws.classloader.CompoundClassLoader@6bd156d5 Local ClassPath:"*
...[the entire classpath]...
Original exception--- java.lang.UnsupportedClassVersionError:
I'm guessing that my focus should mostly be on the 'Original exception', and maybe I need to revisit the JRE or JDK or JVM (these terms are somewhat nebulous to me, so please forgive me using them interchangeably) on my machine. For now, I'll just keep trying stuff. Thanks again for the replies!
Regards,
Daniel T.

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===
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===
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please your comment for this problem.
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-------- Original Message --------
Subject: [Fwd: downloading packages and class files]
Date: Wed, 19 Jan 2005 13:14:24 -0700
From: Jim Litton <[email protected]>
Newsgroups: weblogic.developer.interest.portal
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Message was edited by:
dayrinni
Message was edited by:
dayrinni

Hi,
I have an app that is in a jar file with the .class
files (so no source code).
I'm wondering how difficult it is to attain the
source code from these .class files in my jar?
Looking through the contents of the .class files it
seems there is a large amount of readable text. For
example I see method names, variables, etc.
This leads me to believe these jars are not secure.
What is a better way?
Thanks!
Edit:
Looking around, I've noticed many java decompilers
and Sun even supports a dissembler - javap. I think
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What way can I protect my code? To me, the value of
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source code (based on what I read in the past hour or
so. I have yet to try it myself). I wonder if this
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Kevin Price wrote:
Hello.
I am new to working with WAR files and the whole process of it. A little
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other item.
1) I would like to precompile the JSPs if possible prior to putting into the
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was working with ibm's app server that gave us the ability to do a batch
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>
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section of the build.xml file for ant, I tell it where the source files are,
and the destionation folder for the compiled class files. I then try to set
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I may be going about this all wrong, but dont know. Here is the compile
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<target name="compile" depends="prepare">
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classpath="$(lib.home)"
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One note, I've tried many different items in the classpath line, which
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J2EE .class file compiling for jar, ear files.

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*Added* code to existing source file, compiled it, and class file shrunk

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