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how to avoid using javac -cp

I have a Java class which uses a .jar file.
Every time that I want to compile this class, I have to do something like javac -cp ".:myJar.jar" myClass.java and every time that I want to execute it, I have to do the similar thing but with java instead of javac.
Is there a way to avoid doing this?
I know that I could put this jar file into my class path but I don't want to do that. I don't neither want to do a maven projet.

There is nothing preventing you from using an IDE, taking advantage of all its super useful features when developing the program, and then submit just the source code and associated jars to the professor.
Advantages of using IDE that your professor don't need:
Syntax color-coded editors with auto-complete.
Built-in display of javadoc, so you know what all the built-in Java methods do, and how they work.
Instant high-lighting of syntax errors.
Never having to compile the code, since IDE always keeps the code compiled.
Easy single-button execution of the program when you want to run it.
Debugger. Very important feature when your code is not working as you intended.
... more ...

Unix on the Mainframe: COB2 compiler, for Java calling COBOL

I've been working on trying to get COBOL and Java to interact with each other on the mainframe, and have run into trouble with specifically the cob2 compiler, which is the Unix on the mainframe equivalent.
I haven't seen many user experiences with this compiler online, so I was wondering if I asked a more direct question, people would reveal their insight.
IBM has several examples of Java calling COBOL DLL's either directly or indirectly, but they ultimately boil down to compile the COBOL as a dll, use System.load, compile Java and run. These examples haven't worked for me for the following reasons.
When using cob2 with the -c option, it is purported to generate a .o object file. This has not happened for me, although it did generate an empty .lst file. I was able to get around this by simply skipping the -c step and compiling and linking using this series of commands:
` sh ${COB2HOME}/bin/cob2 -o ${DIR}/c2jcr.o
-qdll,thread,case=mixed ${DIR}/c2jcr.cbl;
${COB2HOME}/bin/cob2
-o ${DIR}/libc2jcr.so
-bdll,case=mixed ${DIR}/c2jcr.o
${JAVAHOME}/bin/j9vm/libjvm.x
${COB2HOME}/lib/igzcjava.x `
This appears to provide the .so library that is required for link with the Java program, but upon investigation of the load, and during run, the system declares that the LE CSECT CEESTART is not there.
Am I missing something in my cob2 library that has these LE modules, or somewhere in my scripting? I tried pulling in loads from the mainframe compiled with the LE modules intact and ENTRY CEESTART explicitly stated in the link step, but could not get any further than "UnsatisfiedLinkError" with "Internal Error".
Any wisdom is greatly appreciated, especially if you've gone down a completely different route to call COBOL from Java. Thank you very much.

After conferring with IBM, it turns out I had a couple things missing.
You must have a STEPLIB environment field set to the location of your COBOL compiler on the mainframe, so it can find your IGYCRCTL module.
Second, like other COBOL 5+ compiling, you must allocate a gargantuan amount of space in order to compile. 2 GB is not enough. Since I don't have permission to reallocate this in Unix, I ran a BPXBATCH job with REGION=0M.
After those two changes, -c compiles came out as normally. The "workaround" I provided in the question is completely incorrect. You must use:
sh ${COB2HOME}/bin/cob2 -c -qdll,thread,case=mixed ${DIR}/${COBPROG}.cbl
as your compile step, and the rest is just linkage.

Java files are not compliling

I have deploy my java code on AWS cloud, when I compile it on windows through terminal, I just have to use the command.
javac mainApp.java
it automatically create .class files of all other classes, lets say I have another class
class newProcessClass
who's variable is in mainApp.java, on EC2 when I compile it, it is giving me the error
error: could not find this symbol
newProcessClass npc = new newProcessClass();
same for the other classes. how can I compile it, and run it.

According to your description, I think that might be caused by classpath issue,
So please make sure current path(.) is under your classpath.
You can do this by type the follow into your terminal(pay attention to the little dot please!)
export CLASSPATH=.;$CLASSPATH
If you would like to persistent this setting and avoid set this everytime, you'd better add it to your .bashrc file.
And then when you run the class via java command, please also specify classpath as below
java -cp . mainApp

I recommend use Maven for the life cycle for application java and when you compiled the mainApp.java this action has that compile all file. you can get me more information of error stack?. For other side I think that is best that you use Maven. Best regards

GLD Green Light Simulator not compiling

I found a traffic light simulator called Green Light District
the file I download included and explanation of how to build the project
and it says the following
Extract the archive to a certain directory,
In that dir do javac gld/*.java
In that dir do java gld.GLDSim
I know * means all but...
first I want to know am I able to compile something like *.java
this is a link to the simulator , if some one can tell how to compile it , it would be really nice
http://sourceforge.net/projects/stoplicht/

The issue occurs due to the fact that "enum" became reserved word in Java 1.5+, so it can no longer be used as a name for variables/methods/classes, but GLD uses enum as a name for some variables.
Once the name is changed - project will compile.
Alternatively one can try to compile it with compiler setting source version 1.4 - this should probably also work, but I suggest to simply rename all variables named enum.

Basically, all the code is in the folder called gld. You need to compile all the .java files inside it. After that, you run the main class gld.GLDSim.

Had the same problem.
You should use Java 1.4, this simulator is quite old, hence uses an old version of Java and some preserved words in more advanced Java versions.

java.lang.NoClassDefFoundError for nested class at run-time? (Dependency problems?)

Ok, here's the situation:
I have three files:
1. TScan.java
2. Test.java
3. ScanServlet.java
I write my mail class, TScan in the TScan.java file, and inside that class, there is a nested class (not a sub-class), called TEntry. TScan has a main() used for testing and other methods that use the nested TEntry class with no problems.
Also, Test.java is a fancier testing program that uses items from TScan.java, including the TScan and TEntry classes with no problems. TScan.java and Test.java were developed and tested in Eclipse (and it compiles/runs fine from the command line as well).
So TScan is working to a useful point, and I wanted to include it in a webapp. Installed Jetty and wrote ScanServlet.java, which runs in Jetty, no problems.
I started referencing TScan and it started giving the error above for TScan. Changing the ClassPath to include the TScan.class file didn't work, so I made a JAR file and stuck it in the WEB-INF/lib/ folder of the WebApp, and now ScanServlet compiles filen, and seems to find TScan at run-time, however it gives the NoClassDefFounfError TScan$TEntry at run-time. This doesn't make sense to me, since:
1. Obviously it's finding the TScan class now (Since it's not complaining about that at compile or run-time)
2. The error occurs in the TScan.java file (TEntry isn't reference directly except by TScan), which runs fine in stand-alone mode!
3. I made TEntry public, and it still doesn't work.
I have found a lot of questions about NoClassDefFoundError, but none dealing with nested classes, especially with Jetty.
Bear in mind I am more used to Delphi, where if it compiles, it runs. (And ABAP which is more or less the same).
If someone has a solution I will be thrilled, otherwise, I am considering:
Copy-Paste the whole TScan into ScanServlet (Shouldn't have a problem finding it if it's in the same file!) (not very modular)
Move TEntry into a separate class in a separate .java file? (May be a pain to cleanly extract).
Have ScanServlet call TScan.Java as a command line program. (Slow...)

How have you created your jar file and does it contain TScan$TEntry.class in the correct folder?
An inner or nested class still produces a .class file which you need to ship

Looks like you are limping along because your not using any formal build tools that apply rigor and convention to your development. Before messing around what is where and how to manage your handful of classes...start using a real build system that produces a jar file that contains what you need. Maven, Ant, Buildr, whatever...something that applies some convention or configuration. Don't leverage anything any IDE gives you in terms of compiling or exporting something that is supposed to be runnable...you can't trust any of that bunk.
With a proper build mechanism and ideally declarative dependencies and the like you can address your issue in a iterative fashion to resolve the NCDFE. my 2 cents at least
[edit]
On your specific issue, I suspect your running into the webapp classloader configuration. By default classes in /lib are not exposed to webapp contexts. You will need to setParentLoaderPriority on the webapp context to true or bundle your classes as a war file. Also use --dry-run on the cli to help sort out what jar files are being loaded up by jetty.