Build failed question - maven - jre or jdk problem

Question

Hi all,

I have my JAVA_HOME set to

C:\Program Files (x86)\Java\jdk1.6.0_18

After I run maven install I get this message from eclipse:

Reason:

Unable to locate the Javac Compiler in:
  C:\Program Files (x86)\Java\jre6\..\lib\tools.jar
Please ensure you are using JDK 1.4 or above and
not a JRE (the com.sun.tools.javac.Main class is required).
In most cases you can change the location of your Java
installation by setting the JAVA_HOME environment variable.

I'm certain that this is the tricky part

Please ensure you are using JDK 1.4 or above and not a JRE

When I run configuration its set to JRE6, how do I change it to JDK 1.6 which I have already installed

EDIT

I even tried to modify the plugin :

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.0.2</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                    <executable>C:\Program Files (x86)\Java\jdk1.6.0_18\bin</executable>
                </configuration>
            </plugin>

Still I get the same error

Maybe I forgot to say I use eclipse maven plugin .. how can I change from JRE to JDK in eclipse ?

Answer 1

I would guess that the location of the compiler is defined in a pom for the compiler plugin to be in the jre location displayed, instead of the jdk location you have JAVA_HOME pointing to.

Answer 2

You could try updating the JDK Eclipse is using, as follows:

Add and set the JRE in Window->Preferences...->Java->Installed JREs:

JRE type: Standard VM JRE 
Name: jdk1.6.0_18
JRE home directory: C:\Program Files (x86)\Java\jdk1.6.0_18

If this is not the case, it's possible that the brackets and spaces in the JAVA_HOME path are causing issues. Try copying your JDK to a different location and updating your JAVA_HOME.

Answer 3

It sounds like Maven is using the JRE, not the JDK. Perhaps you installed Maven before installing the JDK?

Check the settings files. There are 3 in total, system, user, and project. Its most likely in the installation config ($M2_HOME/conf/settings.xml) or, possibly, the per-user config (${user.dir}/.m2/settings.xml).

Answer 4

I got the same problem using Run as -> Maven install in Eclipse. JAVA_HOME and eclipse.ini were OK and pointing to my latest JDK. But m2clipse used JRE. Using mvn install outside of Eclipse worked fine! In my case I solved the problem as follows: 1. Navigate in Eclipse: Window -> Preferences -> Java -> Installed JREs 2. There were two inactive entries for a JRE and JDK. The active one was the latest installed JDK. Delete all entries but the one maven should use.

I think maven doesn't take into acount which one is active...

Answer 5

I had EXACT the same problem! Been searching and searching for days because all the babble about "put the -vm c:\program files\java\jdkxxxxx\bin" in the ini ar as argument for a shortcurt did NOT AT ALL heklp! (Do I sound frustrated? Believe me, that's an understatement! I am simply furious because I lost a week trying to make Maven reliable!)

I had very unpredictable behavior. Sometimes it compiled, sometimes not. If I did a maven clean, it could not find the compiler and failed. If I then changed something in the build path, it suddenly worked again!!

Until I went to window -> preferences -> java -> installed JRE's. I added a new JRE using the location of the JDK and then removed the JRE. Suddenly maven ran stable!

Maybe this is worth putting in letters with font-size 30 or so in the apache manual? With all due respect, this is sipmly outrageous for the java community! I can't imagine how many days were lost by all these people, trying to work out their problems of this kind! I cannot possibly imagine this is released as a final version. I personally would not even dare to release such a thing under the name BETA software...

Kind regards either way.... After a week of tampering I can finally start developing. I hope my boss won't find out about this. It took me lots of effort to convince him NOT to go to .NET and I already feel sorry about it.

Answer 6

Right click on Project -> Properties -> Java Build Path. Select the JRE System Path -> Edit. Select the Workspace Default JRE, and point it to JDK > 1.4