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javac: invalid flag: .getting error when compiling a java servlet

i run command
javac -classpath /home/coolhunk/JBoss/jboss-6.0.0.Final/common/lib/jboss-servlet-api_3.0_spec.jar -d helloapp.war/WEB-INF/classes -sourcepath src/com/manning/jbia/intro/*
for generating java class files.but i am getting error
javac: invalid flag: src/com/manning/jbia/intro/HelloWorldServlet.java~
Usage: javac <options> <source files>
use -help for a list of possible options
can anyone please point out what is the mistake in this command ??

Try these commands using tomcat, place your servlet source in src folder and run these,
C:\Documents and Settings\ssit>cd C:\src
C:\src>javac -classpath "C:\Program Files\Apache Software Foundation\Tomcat 6.0\
lib\servlet-api.jar" MyServlet.java
you can get the class file for the servlet. After getting the class file make the war file.

javac -classpath /home/coolhunk/JBoss/jboss-6.0.0.Final/common/lib/jboss-servlet-api_3.0_spec.jar -d helloapp.war/WEB-INF/classes -sourcepath src/com/manning/jbia/intro/*
The problem is the last item. The wildcard causes it to be expanded into everything in the directory, which causes everything after the first expansion to be treated as a source file name. The expansions also appear to include src/com/manning/jbia/intro/HelloWorldServlet.java~, which the compiler doesn't want to know about.
Try this:
javac -classpath /home/coolhunk/JBoss/jboss-6.0.0.Final/common/lib/jboss-servlet-api_3.0_spec.jar -d helloapp.war/WEB-INF/classes -sourcepath src src/com/manning/jbia/intro/*.java

GCC option not found while constructing .dll

I'm trying to create a .dll while following this tutorial (http://www3.ntu.edu.sg/home/ehchua/programming/java/JavaNativeInterface.html) to use JNI in my eclipse project. There's an issue with my makefile however that may be unrelated to all the JNI stuff.
I'm getting "unknown option: --add-stdcall-alias" when I build (make all). I'm using the Mac GCC Compiler. Here's my console log and make file:
EDIT: So i removed the option that is giving me the error and my build worked. However, I feel unsafe just removing a line of code that I am clueless about. Any one want to tell me the implications of removing this code?
console output:
18:05:33 ** Build of configuration Default for project HPA* Testing *
make all
javah -classpath ../bin HPAProgram
gcc -Wl,--add-stdcall-alias -shared -o hpaprogram.dll HPAProgram.o
ld: unknown option: --add-stdcall-alias
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: ** [hpaprogram.dll] Error 1
18:05:34 Build Finished (took 823ms)
makefile:
# Define a variable for classpath
CLASS_PATH = ../bin
# Define a virtual path for .class in the bin directory
vpath %.class $(CLASS_PATH)
all : hpaprogram.dll
# $# matches the target, $< matches the first dependancy
hpaprogram.dll : HPAProgram.o
gcc -Wl,--add-stdcall-alias -shared -o $# $<
# $# matches the target, $< matches the first dependancy
HPAProgram.o : HPAProgram.c++ HPAProgram.h
gcc -I /System/Library/Frameworks/JavaVM.framework/Versions/A/Headers/ -c $< -o $#
# $* matches the target filename without the extension
HPAProgram.h : HPAProgram.class
javah -classpath $(CLASS_PATH) $*
clean :
rm HPAProgram.h HPAProgram.o hpaprogram.dll

I practiced by following the same tutorial, it turned out that it's OK to get rid of "-Wl,--add-stdcall-alias".
BTW, in Mac, you have to use ".dylib" instead of ".so", otherwise you will get error saying "java.lang.UnsatisfiedLinkError: no hello in java.library.path".

How to make a proper Java makefile?

I need to make a makefile for a Java project.
My project is basic. A package which contains my main file and some others packages.
Can someone help me to make a proper makefile for that kind of project ?

Sorry I have not tested so it is likely to fail...
Assuming that what you need is to generate a executable jar file the following should work but I have not tested it.
The Makefile below assumes that your sources are located under ./src and that you are happy to use ./build for intermediary files (which is totally obliterated by the clean target so be careful).
Then 'make' or 'make jar' should generate the jar file.
NAME=MyProject
MAIN_CLASS=MyMainClass
SRC_DIR=./src
CLS_DIR=./build/classes
MANIFEST_FILE=./build/META-INF.MF
JAR_FILE=./$(NAME).jar
SRC_FILES=$(shell find $(SRC_DIR) -iname "*.java")
CLS_FILES=$(patsubst $(SRC_DIR)/%,$(CLS_DIR)/%,$(patsubst %.java,%.class,$(SRC_FILES)))
.PHONY: jar run clean mrproper
jar : $(JAR_FILE)
run : $(JAR_FILE)
java -jar $(JAR_FILE)
$(JAR_FILE) : $(MANIFEST_FILE) $(CLS_FILES)
jar cmf $< $# $(CLS_DIR)
$(MANIFEST_FILE) :
mkdir -p $(dir $#)
echo Main-Class: $(MAIN_CLASS) > $#
$(CLS_DIR) :
mkdir -p $(CLS_DIR)
$(CLS_DIR)/%.class : $(SRC_DIR)/%.java $(CLS_DIR)
javac -d $(CLS_DIR) -sourcepath $(SRC_DIR) $<
clean :
rm -Rf ./build
mrproper : clean
rm -f $(JAR_FILE)
Each time you execute Make it performs a find operation to get the list of source files, that might cause some delay depending on how many files and how fast is the file-system.... but you said is is a small project so it should not be an issue.
The double patsubst might well be compressed into a single one but I did it in two steps just in case.
Also notice that this solution compiles each Java class separately. This can be quite costly and it might be advisable to have another target to compile all at once ideally by creating a file that contains the name of all src java files and passing it to javac.

compile files from different directories with javac, referring a depending jar file?

I have the following set up:
I have 4 packages:
root/src/terminal - has some java files
root/src/mail - has some java files
root/src/data - has some java files
root/src/main - has a single java file, Main.java
I also have the following files
root/bin - a folder to store .class files
root/mail.jar - a jar file which has important classes used in my code
Within the root, I would like to enter a terminal command which compiles root/src/main/Main.java and puts the class files in the root/bin location.
Can someone show me the command to do this? I'm on a Mac (running Leopard).

Here's the one liner:
cd /xyz/root
rm -rf bin/*
javac -d bin -classpath mail.jar -sourcepath src main/Main.java
Alternatively, you could use absolute directory names:
rm -rf /xyz/root/bin/*
javac -d /xyz/root/bin -classpath /xyz/root/mail.jar \
-sourcepath /xyz/root/src /xyz/root/ main/Main.java
In reference to Ant you said "I would rather keep it simple.".
In fact in the long term it is simpler to create a simple Ant build.xml file. The alternative is a bunch of non-portable scripts or batch file ... or lots of typing.
To run the application, assuming that you are still in the /xyz/root directory:
java -classpath bin:mail.jar main.Main
Or on Windows:
java -classpath bin;mail.jar main.Main
Or modify the above to use absolute pathnames in the classpath argument; e.g.
java -classpath /xyz/root/bin:/xyz/root/mail.jar main.Main

Without knowing your operating system?
What you should look into is using Apache Ant. It is a build tool that once installed and configured can utilize a build.xml file in your root to compile class files to a folder as well as package a jar file.
http://ant.apache.org/

try this:
javac -cp "/root/mail.jar;/root/src;" -d "/root/bin" Main.java
This is written hoping that you have package declarations in your classes from src folder like package terminal; and package main;.
See this: Options in javac command
Or use Apache Ant as suggested by maple_shaft.
From comment give by #maple_shaft:
In Unix, Linux operating systems the classpath separator is a colon instead of a semicolon.

Compiling multiple packages using the command line in Java

Hi i have been using an IDE but now I need to run and compile from the command line.
The problem is that I have multiple packages and I have tried to find the answer but nothing has worked.
So I have
src/
Support/ (.java files)
Me/ (.java files)
Wrapers/ (.java files)
Do you know how to compile everything with javac?

This should do it (may require additional classpath elements via the -cp command line switch):
javac Support/*.java Me/*.java Wrapers/*.java
But if your build process gets more complex (and it will!), you should look into using Apache Ant for build automation.

You should use build tools like Maven or Ant for such tasks.
In the initial stages, when the project is not very complex you can use the following line to compile, with appropriate classpath in place(as suggested by #Michael):
javac Support/*.java Me/*.java Wrapers/*.java

javac -d compiled $(find src -name *.java)

If you really need to just use javac and standard UNIX commands you could to this:
find src -name \*.java -print0 | xargs -0 javac -d classes

The real answer is javac -d (places where classes to be built and placed) -sourcepath (source of the package at the root) -cp (classpath of the dependencies which can again be classes folder where the classes are build and kept) full qualified name of the java file.
Ex javac -d classes -sourcepath src -cp classes src\com\test\FirstSample.java
The FirstSample.java contains the main method. Pacjage structure mentioned below.
Before compiling
HomeApp
--src
------com\test\FirstSample.java (First Sample using the FirstPojo.java)
------com\test\FirstPojo.java
--classes
After compiling
HomeApp
--src
------com\test\FirstSample.java (FirstSample.java using the FirstPojo.java)
------com\test\FirstPojo.java
--classes
------com\test\FirstSample.class (FirstSample.class using the FirstPojo.class)
------com\test\FirstPojo.class

In many cases Ant is overkill. Just use a BAT file if you are in windows or a shell script (sh file) if you are in linux. You can create a text file which includes all your javac commands and just run that file when you want to build.
For example, I use the following bat file to build one of my apps:
#echo off
echo Building Shazaam...
del classes\com\aepryus\shazaam\*.* /q
del classes\com\aepryus\shazaam\engine\*.* /q
del classes\com\aepryus\shazaam\domain\*.* /q
del classes\com\aepryus\shazaam\persist\*.* /q
del classes\com\aepryus\shazaam\view\*.* /q
del classes\com\aepryus\shazaam\task\*.* /q
del classes\com\aepryus\shazaam\action\*.* /q
del classes\com\aepryus\shazaam\controller\*.* /q
javac src\com\aepryus\shazaam\*.java -classpath \lib\AepUtil.jar;\lib\AepXML.jar;\lib\AepLoom.jar; -d classes
javac src\com\aepryus\shazaam\engine\*.java -classpath \lib\AepUtil.jar;\lib\AepXML.jar;\lib\AepLoom.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\domain\*.java -classpath \lib\AepUtil.jar;\lib\AepLoom.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\persist\*.java -classpath \lib\AepUtil.jar;\lib\AepLoom.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\view\*.java -classpath \lib\Servlet.jar;\lib\AepUtil.jar;\lib\AepXML.jar;\lib\AepLoom.jar;\lib\AepHTML.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\task\*.java -classpath \lib\AepUtil.jar;\lib\AepLoom.jar;\lib\AepHTML.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\action\*.java -classpath \lib\Servlet.jar;\lib\AepUtil.jar;\lib\AepLoom.jar;\lib\AepHTML.jar;\lib\Sprout.jar;classes; -d classes
javac src\com\aepryus\shazaam\controller\*.java -classpath \lib\Servlet.jar;\lib\AepUtil.jar;\lib\AepXML.jar;\lib\AepRPC.jar;\lib\AepLoom.jar;\lib\AepHTML.jar;\lib\Sprout.jar;classes; -d classes
cd classes
jar cf ..\war\WEB-INF\lib\Shazaam.jar .
cd..
echo Complete

To compile Run below command [it will store all class files in classes folder]
javac -d classes Support/*.java Me/*.java Wrapers/*.java
**Note : classes folder should be created first
To Run java application, run below command
java -cp classes {mainfile_name}
Replace mainfile_name with your main file.