Java running old class file

When I make a change to a Swing program and compile, it runs the old version, as if the changes were never made. Any ideas?
I make a new directory and copy the java file, re-compile and it works...but I don't want to have to do that every time.
Dan

If you have like
class1.java
class2.java
class3.java
class1.class
class2.class
class3.class
then make changes to class1.java and class2.java, then run javac class1.java, it will see that class2.class exists so it won't bother to recompile class2.java, either delete all the classes or do javac *.java
Shish

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How to run a class file in MAC os, compiled in XP.

Hi all,
i am compiling a java program in windows using JDK 1.5 and i am copying this file to MAC os (Panther). In Mac i am running this class file using JDK 1.4.i am getting the following exception,
Exception in thread "main" java.lang.UnsupportedClassversion error.
This is understandable, but is there any solution for this ...
Any one experienced the same problem ...
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You are compiling it in 1.5 and expecting 1.4 to run it?
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How to clear old class files cached in JVM

JVM stores old class files in its cache even after the corresponding files have been deleted from the database. This causes a conflict if a new file is saved with the same name as one that was deleted earlier causing old data to be fetched and not the new one.
am using the following line of code to load the class file :
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Why are you trying to do that?
Dynamic Classloading(reloading) has a meaing only on "application container" like WAS.
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Focus on enhancing your application logic and algorithm rather than wasting your brain on difficult and meaningless things. Applying some flexible design patterns wouldn't suffice?
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Edited by: Dion_Cho on Nov 26, 2007 5:18 PM
Typo...

Compiling on a dual core machine and running the class files on linux.

does compiling on a dual core machine and running the class files on linux have any effect?

well, the problem that i felt was that when i runmy
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I can't be 100% sure, but I'm pretty sure that
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Due to timing issues it may seem to sleep a few milliseconds more, but not double.
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Hi Friends,
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I have experienced this problem before as well. Tomcat seems to cache compiled class files for better speed. To get Tomcat to reload class files that I've recently recompiled here is what I do:
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What happened when you tried what you have there?

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When run with just java I get this:
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Java wont open .class file

ok i just started at this and found this web site http://java.sun.com/docs/books/tutorial/getStarted/cupojava/win32.html#1
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Exception in thread "main" java.lang.NoClassDefFoundError: helloworldapp (wrong
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thanks it worked. can you tell my why?

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Also, Javadoc 1.4.2 will contain an unsupported option -Xclasses
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alright i'll look it up, the little i've done with
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Hi,
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Im new to running java from a shortcut but this may help. I hope this helps.
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I searched for the same and found the following article in many places which doesnt seem to help me much.
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Hi;
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Regard
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Also, is there a way to find out the Java version from JAR file?
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Kavipriya wrote:
I have a .class file. I would like to identify the Java version from that.
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Java running old class file

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