蚂蚁构建-JAVA_HOME变量未更新

Question

I am trying to run an ant build to generate a jar and i get the following error:

Unable to locate tools.jar. Expected to find it in /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.91-0.b14.el7_2.x86_64/lib/tools.jar
Buildfile: /my/path/to/the/required.xml

make:
[javac] /my/path/to/the/required..xml:11: warning: 'includeantruntime' was not set, defaulting to build.sysclasspath=last; set to false for repeatable builds

BUILD FAILED
/my/path/to/the/required.xml:11: Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK.
It is currently set to "/usr/lib/jvm/java-1.8.0-openjdk-   1.8.0.91-0.b14.el7_2.x86_64/jre"

My questions: 1. I did a bit of reading online and i concluded its because i am pointing it to the JRE and not JDK which is why it failed. Initially i did

export JAVA_HOME=readlink -f $(which java)

So i updated and exported my JAVA_HOME variable with output of which javac command. What is interesting is that last part of the error did not display the changed JAVA_HOME value. Why is that?

2. What is this includeantruntime and how to get rid of it? I use ant 1.9.2

Answer 1

You may want to check and update ant configuration file for the JAVA_HOME settings. It is possible that the value for $JAVA_HOME set for your shell in .bashrc can be overridden in the files /etc/ant.conf, $HOME/.ant/ant.conf, and $HOME/.antrc. If you execute bash -x it will print debugging information which should help you track down where $JAVA_HOME is being overridden.

Answer 2

Perhaps its just a matter of where Ant first looks for the java executable (ie in the JAVA_HOME variable or somewhere else).

You can test if this is the case by setting the fork="true" and the executable parameter as described here: https://ant.apache.org/manual/Tasks/javac.html and see if this is the case.

Also, did you actually found the tools.jar in the JVM you're currently pointing your JAVA_HOME at ?