Java compile and run time questions

Hello, I have two generic question about java compile and run:
1. When I used javac to compile my project, it complained some classes can't be found. I added the jar file which contains these needed classes to the jre/lib/ext/ directory. The compiler no longer complains. But I'm confused. I thought the jar files in jre/lib/ext/ only used for java run time, not the compile time. Can someone help me to explain this?
2. If I need certain user defined jar file in the classpath to compile my application, does that imply that I have to have that jar file if I want to run my project?
Thanks in advance.

1. lib/ext is used for generally finding classes, it doesn't matter whether you are compiling or running.
2. Yes, you will.

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i need of a jsp page that has a textarea in which the java coding are entered and this coding is compiled and executed. The execution result is printed.
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I don't think you can invoke java compiler or run time environment at client side (browser). Even if you use applet, i think you will not be able to do it at client side. Moreover, though java virtual machine will be available in your target user's browser, but you should not expect a java compiler in users machine.
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Here you challenge would be managing multiple client requests (to compile and run java class) at the same time.
Code to compile and run java classes:
import java.io.*;
* A class to compile and run java classes.
* @author Mrityunjoy Saha
public class JavaProcessor{
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               readData="";
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          catch(IOException ioe){
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}Thanks,
Mrityunjoy

CLASSPATH, Jar file or zip file visibility during compilation and run time

I am using jwsdp-1_0_01 with some success.
However, making my *.jar or *.zip files
visible during ant builds is not working.
Setting a CLASSPATH environment
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machinery found the JWSDP download
jwsdp-1_0_01/docs/tutorial/examples/jaxrpc/
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and tomcat to see 'mystuff.zip' or 'foo.jar'
or whatever.
Note: I was able to get past these problems
using jwsdp-1_0-ea1 but (sigh) nothing learned there
seems to help here.
-joe

Hi joe
I made changes to targets.xml (in jwsdp-1_0\docs\tutorial\examples\jaxrpc\common) to include my own jar files.
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<echo message="Compiling the server-side source code...." />
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</target>
<target name="compile-client" description="Compiles the client-side source code">
<echo message="Compiling the client source code...." />
<javac srcdir="src" destdir="${build}/client" classpath="${jwsdp-jars}:build/shared:build/client:C:\jwsdp-1_0\common\lib\genericbroker.jar:C:\jwsdp-1_0\common\lib\weatherdata.jar" includes="net/agmodel/metsoap/*Client.java" />
</target>
Hope this helps.
Good luck
Matthew

Compile and run java programs in different directroy

Hi,
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java -cp dir_name a
Something wired often happens, such as, there is not a.java file in some directory, but javac -d dir_name a.java can still work or "java -cp dir_name a" often doesn't work. Moreover, file_name.jar is also a tough problem and solving compiling problems is often time-consuming.
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Can you post a small amount of code that does not work, including the directory structure, and the error messages? Some one here can likely explain the problem.

How do I compile and run Java programs on a Mac?

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See this question :-)
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When I use Runtime.getRuntime().exec(command) for executing the AspectJ compile command "ajc", "IOException createProcess error=2" always occurs, while it is ok for Java comiple command "javac".
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Runtime.getRuntime().exec ("c:\\programs\\java className");
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Hi,
I want to know how to compile and run the package programs in Java using -d. instead of creating the package folder manually.
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Thanks in Advance ,
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Test.java
package com.cert;
public class Test
public void display()
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javac: no source files
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How to compile and run a java program?

I am getting this error message, what to do?
Exception in thread "main" java.lang.NoClassDefFoundError:
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Ajay

Hello,
I believe that this error is caused because when you
compile and run a java program, you have to use the
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the program name is next to the word public class.
For example, if a program began like this:
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hello,
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Well a smarter way of implementing this is by using a solution provided by Java Itself.
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http://www.ibm.com/developerworks/java/library/j-jcomp/index.html
http://www.javabeat.net/javabeat/java6/articles/java_6_0_compiler_api_1.php
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Hope that might help :)
REGARDS,
RaHuL

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try this
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Compile and run java programs using batch file

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Java compile and run time questions

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