如何编译这个Java应用程序

Question

I need to compile the Java app from this code on Windows:

http://www.falstad.com/vector3dm/base.java

The comments at the to mention that

// this file must be run through cpp with one of BUILD_E, BUILD_V,
// BUILD_M defined before compiling with java compiler.  This was done
// to reduce class file sizes.

I don't know what it means. Does cpp stands for C++ compiler? How do I run it on this java code? I see some #define statments in the code. Being a Java code I would expected 'javac base.java' to just work

Can someone please explain what I need to do in order to compile the code.

Thank you.

EDIT:

@Ahmed Masaud:
I downloaded anarres-cpp-bin-1.2.6.tar.gz from the annarres website and extracted in my JDK directory. Here is what I have now:

C:\\Program Files\\Java\\jre6\\bin\\base.java

C:\\Program Files\\Java\\jre6\\lib\\anarres-cpp.jar

C:\\Program Files\\Java\\jre6\\lib\\gnu.getopt.jar

When running the command you indicated

java -Xmx128M -cp lib/anarres-cpp.jar:lib/gnu.getopt.jar org.anarres.cpp.Main -o base-e.java -DBUILD_E base.java

and here is what I get:

Exception in thread "main" java.lang.NoClassDefFoundError: org/anarres/cpp/Main Caused by: java.lang.ClassNotFoundException: org.anarres.cpp.Main at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) Could not find the main class: org.anarres.cpp.Main. Program will exit.

it looks like it can't find 'org.anarres.cpp.Main'

Answer 1

CPP means C-preprocessor not C++. What they are asking you to do is to run it with a particular define:

If you are using linux you can do this by typing

  cpp -o base-e.java -DBUILD_E base.java

this will create a base-e.java file which uses the BUILD_E options in base.java

If you are using windows grab mcpp:

http://mcpp.sourceforge.net/download.html

and use mcpp to do the same thing.

There is an alternate jcpp which is a C pre-processor written in java:

http://www.anarres.org/projects/jcpp/

may be better choice.

jcpp is pretty close to the GNU cpp; as it's based on it, so the command-line above should work, and a pre-compiled version is available on that site so:

java -Xmx128M -cp lib/anarres-cpp.jar:lib/gnu.getopt.jar org.anarres.cpp.Main -o base-e.java -DBUILD_E base.java

Proper command-line:

java -Xmx128M -cp ./lib/anarres-cpp.jar:./lib/gnu.getopt.jar: org.anarres.cpp.Main -DBUILD_E base.java > base-e.java

There is no -o flag support in jcpp

make sure you put base.java in the anarres-cpp-bin-1.2.6 folder and then run the above command from in there.

you can then move the base-e.java wherever you like.

alternatively you can provide full paths to base.java and base-e.java on command line etc.