How to generate Make Files?

[aMax]

I would like to automate the recompile of large application having several
packages.

[Paul Clapham]

I suspect the reason that Java doesn't have a "make" facility is that mass
recompiles are rarely necessary. You only need to recompile a class if it
uses a method of another class and that method no longer exists, or its
parameter list has changed, and only to track down such errors. (Of course
this is something that you would try to avoid doing.) The other reason for
a mass recompile could be when you move to a new version of the compiler.
In any case, "javac *.java" will recompile all Java sources in a directory.

aMax <arun@stones.com> wrote in message news:39874381$1@news.devx.com...
>
> I would like to automate the recompile of large application having several
> packages.

[Jo Desmet]

One of my first rules is always to do a mass recompile and even delete all
class files before doing that, unless I am 100% certain that there are no
dependencies with the parts I do not want to recompile. Here comes the
important task of carefully designing your packages, separating in logical
independent units. This will also help you to reuse those packages into
other projects without modification, or without forcing you to move the
whole library set into your new project.

Way to often I see people creating cross-dependencies. Everything works
while they are coding, but when the release is there the code wont compile
properly, or the release will show crashes (and you thinking that java can
not crash).
At least for the release, there should be a clean-make, but then stress is
high, and time low ...

To be honnest, I feel that a makefile doesnt work properly with java, and I
tend to make script or batch files for each of the packages that I want to
generate. You can even go further by generating javadoc, jar files and even
executing test code within the compiled packages to track unexpected changes
in output. Here is an example batch file (for ms-dossers, but translates
easelly into csh).

[start example: make.bat]
@echo off

SETLOCAL

rem This is a bat file wich compiles the entire JMEP project and place
rem it in a jar file. The final results are tested and any results can
rem be found at %TESTDIR%\report.txt

rem This batch file is meant to run on any configuration. You only need to
rem change the JAVADIR and BASE environment variable to reflect your set up.

rem To let this work with the zip file I always send to you, you have to
rem extract the whole contents of the zip file to a directory and define
rem BASE to point to the same directory (here this directory is
rem d:\data\projects\jmep).

rem The JAVADIR environment variable has to point to the base installation
rem directory of your java distribution. The java executables should be
found
rem at %JAVADIR%\bin

rem Define where you can find the java binaries
rem TODO: Change this to let this point to your path
set JAVADIR=C:\jdk1.3

rem Define the base directory of the projects
rem TODO: Change this to let this point to your path
set BASE=c:\data\development\jmep

rem Define where the class files and jar files are outputted
rem DO NOT CHANGE
set CLASSES=%BASE%\classes

rem Define a path for temporary storage of class files before
rem making a jar file from it.
rem DO NOT CHANGE
set CLASSES_TMP=%BASE%\jartmp

rem Define a path for temporary storage of class files before
rem making a jar file from it.
rem DO NOT CHANGE
set TESTDIR=%BASE%\test

rem Define a path for temporary storage of class files before
rem making a jar file from it.
rem DO NOT CHANGE
set HTMLDIR=%BASE%\html

rem Define the java compile command
rem REMARK: if needed change javac to javac-ea for better compiler.
rem DO NOT CHANGE
set JAVAC="%JAVADIR%\bin\javac" -O -deprecation

rem Define the javadoc command
rem DO NOT CHANGE
set JAVADOC="%JAVADIR%\bin\javadoc"

rem Define the jar command
rem DO NOT CHANGE
set JAR="%JAVADIR%\bin\jar"

rem Define the java run command
rem DO NOT CHANGE
set JAVA="%JAVADIR%\bin\java"

rem Do some clean-up
rem DO NOT CHANGE
echo Cleaning up ...
if exist %CLASSES_TMP% rmdir /S /Q %CLASSES_TMP%
if exist %CLASSES% rmdir /S /Q %CLASSES%
if exist %HTMLDIR% rmdir /S /Q %HTMLDIR%
mkdir %CLASSES%
mkdir %HTMLDIR%

rem Compile the whole JMEP project and store it in the temporary
rem folder, then make a jar file from it.
rem DO NOT CHANGE
echo Making the jmep project ...
mkdir %CLASSES_TMP%
set CLASSPATH=%CLASSES_TMP%
set SOURCE=%BASE%\java\com\neemsoft\jmep\*.java
%JAVAC% -d "%CLASSES_TMP%" -classpath "%CLASSPATH%" %SOURCE%
%JAR% -cf0 "%CLASSES%\jmep.jar" -C "%CLASSES_TMP%" com
rmdir /S /Q "%CLASSES_TMP%"

rem Making the documentation
rem DO NOT CHANGE
echo Making the documentation...
set CLASSPATH=%CLASSES%\jmep.jar
%JAVADOC% -classpath "%CLASSPATH%" -d %HTMLDIR%
com.neemsoft.jmep -sourcepath %BASE%\java

rem make the TestJMEP application and run it to test if there
rem are any problems.
rem DO NOT CHANGE
echo Making the test application ...
set CLASSPATH=%CLASSES%
set CLASSPATH=%CLASSPATH%;%CLASSES%\jmep.jar
set SOURCE=%BASE%\java\TestJMEP.java
%JAVAC% -d %CLASSES% -classpath "%CLASSPATH%" %SOURCE%
echo Testing the jmep.jar library ...
%JAVA% -classpath "%CLASSPATH%" TestJMEP %TESTDIR%

rem make the CLJMEP example application
rem DO NOT CHANGE
echo Making the example application ...
set CLASSPATH=%CLASSES%
set CLASSPATH=%CLASSPATH%;%CLASSES%\jmep.jar
set SOURCE=%BASE%\java\CLJMEP.java
%JAVAC% -d %CLASSES% -classpath "%CLASSPATH%" %SOURCE%

echo ======================================================================
echo Test results are in %TESTDIR%\report.txt,
echo check to see if any problems.
echo You can extend the tests by adding equations into intput.txt and the
echo expected results into refer.txt.
echo jmep.jar can be found at %CLASSES%,
echo you can copy it into %JAVADIR%\jre\lib\ext,
echo to install it as a java extension.
echo You can start the example with the example.bat script file.
echo ======================================================================

ENDLOCAL

[end example]
----- Original Message -----
From: "Paul Clapham" <pclapham@core-mark.com>
Newsgroups: java.enterprise
Sent: Friday, August 04, 2000 10:34 AM
Subject: Re: How to generate Make Files?


> I suspect the reason that Java doesn't have a "make" facility is that mass
> recompiles are rarely necessary. You only need to recompile a class if it
> uses a method of another class and that method no longer exists, or its
> parameter list has changed, and only to track down such errors. (Of
course
> this is something that you would try to avoid doing.) The other reason
for
> a mass recompile could be when you move to a new version of the compiler.
> In any case, "javac *.java" will recompile all Java sources in a
directory.
>
> aMax <arun@stones.com> wrote in message news:39874381$1@news.devx.com...
> >
> > I would like to automate the recompile of large application having
several
> > packages.
>
>