I recently upgraded to Java7 on my Macbook Pro. I downloaded the JDK (not the JRE).
» javac version
javac 1.7.0_17
» echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home
However, when trying to run a build, one of the maven compiler plugins is failing, claiming I have a JRE installed:
» mvn install
[ERROR] execute error
org.apache.maven.plugin.MojoExecutionException: You need to run build with JDK
or have tools.jar on the classpath.
If this occures during eclipse build make sure you run eclipse under JDK as well
at com.mysema.maven.apt.AbstractProcessorMojo.execute(AbstractProcessorMojo.java:263)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
I'm confused, as I clearly have a JDK installed. My MAVEN_OPTS
don't do anything funny:
» echo $MAVEN_OPTS
-Xmx512m
Trying to debug, I checked the source of the plugin in question, which is doing the following:
try {
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
if (compiler == null) {
throw new MojoExecutionException("You need to run build with JDK or have tools.jar on the classpath."
+ "If this occures during eclipse build make sure you run eclipse under JDK as well");
}
That seems harmless, so I suspected something wrong on my command line env, and wrote a simple test:
// Main.java
import javax.tools.JavaCompiler;
import javax.tools.ToolProvider;
public class Main {
public static void main(String[] args) {
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
if (compiler == null)
{
System.out.print("Compiler is null");
} else {
System.out.print("Compiler is not null");
}
}
}
» javac Main.java
Main.java:1: cannot access javax.tools.JavaCompiler
bad class file: /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home/jre/lib/rt.jar(javax/tools/JavaCompiler.class)
class file has wrong version 51.0, should be 49.0
Please remove or make sure it appears in the correct subdirectory of the classpath.
import javax.tools.JavaCompiler;
^
1 error
If I understand that error correctly, it suggests a Java7 compiler running against a Java5 rt.jar
?
I'm not sure what's going on here.
I clearly have a Java7 JDK installed, but don't understand:
Answers are suggesting a messed up JRE / JDK install. I agree this seems likely, but having trouble tracking down where the culprit lies.
Some additional info:
» which javac
/usr/bin/javac
ls -ltra /usr/bin/javac
/usr/bin/javac -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/javac
cd /System/Library/Frameworks/JavaVM.framework/Versions
ls -ltra
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.6.0 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.6 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.5.0 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.5 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.4.2 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.4 -> CurrentJDK
drwxr-xr-x 8 root wheel 272 18 Feb 08:39 A
drwxr-xr-x 11 root wheel 374 18 Feb 08:39 ..
lrwxr-xr-x 1 root wheel 1 14 Jun 11:14 Current -> A
lrwxr-xr-x 1 root wheel 58 14 Jun 11:15 CurrentJDK -> /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents
drwxr-xr-x 11 root wheel 374 14 Jun 11:15 .
So, the javac that is running is the one installed in A/Commands
. I'm not sure if this is correct or not. It seems wrong from my windows days, but I'm not familiar enough with how Mac treats Java install to go tinkering.
My $JAVA_HOME
points to /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home
, which has the following:
drwxrwxr-x 10 root wheel 340 5 Feb 08:10 jre
-rw-rw-r-- 1 root wheel 123324 5 Feb 08:10 THIRDPARTYLICENSEREADME-JAVAFX.txt
drwxrwxr-x 5 root wheel 170 5 Feb 08:10 man
drwxrwxr-x 9 root wheel 306 2 Mar 02:10 db
-rw-rw-r-- 1 root wheel 3339 2 Mar 02:10 COPYRIGHT
drwxrwxr-x 9 root wheel 306 2 Mar 02:10 include
-rw-rw-r-- 1 root wheel 19997030 2 Mar 02:10 src.zip
-rw-rw-r-- 1 root wheel 447 2 Mar 02:10 release
-rw-rw-r-- 1 root wheel 172252 2 Mar 02:10 THIRDPARTYLICENSEREADME.txt
-rw-rw-r-- 1 root wheel 114 2 Mar 02:10 README.html
-rw-rw-r-- 1 root wheel 40 2 Mar 02:10 LICENSE
drwxrwxr-x 5 root wheel 170 2 Mar 02:10 ..
drwxrwxr-x 15 root wheel 510 2 Mar 02:13 .
drwxrwxr-x 13 root wheel 442 2 Mar 02:13 lib
drwxrwxr-x 43 root wheel 1462 2 Mar 02:13 bin
I found a tools.jar
sitting in /Library/Java/Extensions
I'm not sure if this is standard or not.
However, copying the tools.jar
from the JDK7 $JAVA_HOME/lib
to /Library/Java/Extensions
solved all my problems.
I should also point out that in my original question I had updated the Java CurrentSDK
to point to JDK7
:
CurrentJDK -> /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents
This was a Bad Idea, as pointed out here .
I updated this to point back to 1.6. Although this seems counter-intuitive, it was required to get things working.
The current listing of /System/Library/Frameworks/JavaVM.framework/Versions
with a 1.7
JDK looks as follows:
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.6.0 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.6 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.5.0 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.5 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.4.2 -> CurrentJDK
lrwxr-xr-x 1 root wheel 10 18 Feb 08:36 1.4 -> CurrentJDK
drwxr-xr-x 8 root wheel 272 18 Feb 08:39 A
drwxr-xr-x 11 root wheel 374 18 Feb 08:39 ..
lrwxr-xr-x 1 root wheel 1 14 Jun 11:35 Current -> A
lrwxr-xr-x 1 root wheel 59 14 Jun 12:31 CurrentJDK -> /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents
drwxr-xr-x 11 root wheel 374 14 Jun 12:31 .
The correct way to set JAVA_HOME on MacOS X is to use:
[user@ip ~]$ export JAVA_HOME=$(/usr/libexec/java_home -v1.7)
[user@ip ~]$ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk1.7.0_25.jdk/Contents/Home
Your java installation is broken if, after doing this, $JAVA_HOME/lib does not contain a tools.jar.
Tip: I have these two aliases specified in my ~/.bash_profile:
alias java6="export JAVA_HOME=$(/usr/libexec/java_home -v1.6)"
alias java7="export JAVA_HOME=$(/usr/libexec/java_home -v1.7)"
Placing jars in /Library/Java/Extensions is equivalent to putting them in the global classpath and is rarely a good idea.
Forget Maven.
What directory has the JDK /bin
directory? That's JAVA_HOME
.
I suspect that you've set the environment variable incorrectly.
And that /bin
ought to have all the executables for the JDK tools: javac, java, jar, javap, etc.
If that's not the case, then you don't have JDK, you've got JRE.
I've got a Windows machine. Here's where I have JDK installed:
C:\Program Files\Java\jdk1.7.0_17
And here's JAVA_HOME:
JAVA_HOME=C:/Program Files/Java/jdk1.7.0_02
No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
Maven build failure in eclipse with above error was fixed by un-installing older version of java.
Most probably javac is running from JRE and not JDK. tools.jar is only available in JDK. Confirm the path of javac/java by using which
which javac
Drag correct Java7 version to top in Java Preferences (Launchapad/Others). That should point A to JDK7.
I had a similar issue and found the answer in another thread:
Symbolic link messed up on OSX while trying to change the Java version
I set JAVA_HOME as follows:
export JAVA_HOME=/Library/Java/Home
and it's working now.
If you find that the tools.jar
in /Library/Java/Extensions
is not from the right version of the JDK, then move it out of the way, so that there is no tools.jar there and there is a tools.jar in $JAVA_HOME/lib
(as set in the previous response).
eg
cd
sudo mv /Library/Java/Extensions/tools.jar tools.jar.safe
I got the following error on a maven project: Failed to execute goal on project cobertura-maven-plugin: Could not resolve dependencies for project org.codehaus.mojo:cobertura-maven-plugin:maven-plugin:2.6: Could not find artifact com.sun:tools:jar:0 at specified path /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/../lib/tools.jar -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal on project cobertura-maven-plugin: Could not resolve dependencies for project org.codehaus.mojo:cobertura-maven-plugin:maven-plugin:2.6: Could not find artifact com.sun:tools:jar:0 at specified path /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/../lib/tools.jar
I fixed it by creating a lib dir under /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents and adding tools.jar to it.
Full path would be this for tools.jar in this particular instance: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/lib/tools.jar
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