java plugin does not work with non-openjdk java

[Gabriel Nell]

Binary package hint: collectd

I'm on lucid, and I've installed collectd-core and sun-java6-jdk from the partners repository. Updating collectd.conf to have "LoadPlugin java" results in the following failure:

lt_dlopen (/usr/lib/collectd/java.so) failed: file not found
Unable to load plugin java.

The file referenced does in fact exist. I think what's going on is that java.so was built statically linking to the openjdk location of libjvm.so. Installing openjdk-6-jdk resolved the issue.

The bug here is that the collectd-core package has a hidden dependancy on a specific flavor of java. I suspect this repros on pre-lucid as well.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[frntn (frntn)]

Looking at java.so content we can find the PATH from which it will try load the libjvm.so

> prompt$ strings /usr/lib/collectd/java.so | grep jre
> /usr/lib/jvm/default-java/jre/lib/amd64/server

So I have symlinked this *default-java* to my actual *java-7-oracle* install

> prompt$ ln -sf /usr/lib/jvm/java-7-oracle /usr/lib/jvm/default-java

My plugin is now loaded and ready to use.

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ubuntu trusty 14.04.2 LTS

[Poil (poil)]

Hi,

A better way is to declare in /etc/default/collectd
LD_PRELOAD=/etc/alternatives/jre_1.8.0/lib/amd64/server/libjvm.so

Like that if we have openjdk 1.7 and 1.8 installed (or Java Oracle) on our host collectd jmx will work

[Andreas Steffan (a-steffan)]

Personally had no issues with artful, but the issue appeared with bionic where default-java symlinks to openjdk-11-jre-headless which has libjvm.so in a different directory (and not below jre/lib/amd64/server where it is expected by java.so).

My quick hack was:

patchelf --set-rpath '/usr/lib/jvm/default-java/lib/server' java.so