"jar" not found

[andrea5w]

Hello!!!

I am running configure on my (standard) Ubuntu machine, and when I run configure, the scripts stops with the following error:

checking for gcj... no
checking for guavac... no
checking for jikes... no
checking for javac... javac
checking if javac works... yes
checking if javac supports -h... yes
checking for javac... /usr/bin/javac
checking symlink for /usr/bin/javac... /etc/alternatives/javac
checking symlink for /etc/alternatives/javac... /usr/lib/jvm/jdk-14.0.2/bin/javac
checking jni headers... /usr/lib/jvm/jdk-14.0.2/include
checking for jar... no
configure: error: no acceptable jar program found in $PATH

The error goes away when I install a package like "default-jdk".

I suggest to adjust the configure script so that it does not terminate with an error message if "jar" is not found; this can be annoying if one wants to install Ipopt but does not need the java interface.

[svigerske]

I even have comment on that in configure.ac:

Ipopt/configure.ac

Lines 413 to 422 in bae155b

	if test "$enable_java" != no ; then
	# the following macros can make configure stop with an error
	# we could work around that, but having javac and no jar, java, or javadoc would be odd anyway
	# look for jar: required to pack Java interface
	AX_PROG_JAR
	# look for more java to run tests and examples and do documentation
	AX_PROG_JAVA
	AX_PROG_JAVADOC
	fi

So if passing --disable-java is not a viable option, we can look into adding more flexibility. Unfortunately, that would mean to not use the AX_PROG_JAR macro. (PS: ok, that macro has very little own logic anyway)

[andrea5w]

Great! Then let’s disable Java by default. I’m sure I’m not the only one who runs into this issue, and probably more people have issues than people using Java. If someone wants to use Java they already know they are doing something special and can expect to pay more attention. And even after I installed jar the test failed which would be concerning for a simple user.

…

On Sep 8, 2021, at 03:44, Stefan Vigerske ***@***.***> wrote:  I even have comment on that in configure.ac: https://github.com/coin-or/Ipopt/blob/bae155b51f127a5b89f1eae8eadc6ac40d43785f/configure.ac#L413-L422 So if passing --disable-java is not a viable option, we can look into adding more flexibility. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications on the go with GitHub Mobile for iOS or Android.

[svigerske]

But I have already changed configure to only give a warning and disable the build of the java interface if jar is not around, see the commit that closed this issue. So now, the Java interface isn't build anymore if there is no javac or no jar and the test is skipped if there is no java.