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Error: Could not find or load main class $MAVEN_HOME

while running maven clean I am getting the following error :
Error: Could not find or load main class $MAVEN_HOME
while doing mvn -version I got :
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-10T22:11:4
7+05:30)
**Maven home: D:\mavenSecurity\apache-maven-3.3.9\bin\..**
Java version: 1.7.0_79, vendor: Oracle Corporation
Java home: C:\Program Files\Java\jdk1.7.0_79\jre
Default locale: en_IN, platform encoding: Cp1252
OS name: "windows 7", version: "6.1", arch: "x86", family: "windows"
I have set MAVEN_HOME = D:\mavenSecurity\apache-maven-3.3.9 in user variable in environment setting
Path in system variable in environment setting : D:\mavenSecurity\apache-maven-3.3.9\bin
Since I am getting other error previously so I have done the following also as mentioned in this post:
Eclipse error setting up Maven project for class exercise: Check $M2_HOME environment variable and mvn script match
-Dmaven.multiModuleProjectDirectory=$MAVEN_HOME
I have consulted other links but still I am getting the error while running MAVEN CLEAN in eclipse juno

This worked for me with the 3.3.9 version. The only difference is :
1) Add both M2_HOME and MAVEN_HOME variables in the Windows environment, and point it to your Maven folder (Note: I have added it to system variables)
2) Update PATH variable, append Maven bin folder – %M2_HOME%\bin, so that you can run the Maven’s command everywhere
Post output of mvn –version again if you face the issue. Also try running mvn clean from the command line and post the results.

configuring Maven on Eclipse. you have to tell eclipse where Maven has been installed so that it can use the Maven installation to build our projects.
Win 7 64 . Here is how i did my config.

Maven: Fatal error compiling: invalid target release: 1.8

We just upgraded the project from jdk 1.6 to jdk 1.8. While building the project in my machine, i'm getting following error.
[ERROR] Failed to execute goal
org.apache.maven.plugins:maven-compiler-plugin:3.3:compile
(default-compile) on project exception: Fatal error compiling: invalid
target release: 1.8 -> [Help 1]
Here is the maven compiler plugin which is been used
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.3</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
I looked at the many post and most of them were related with not having the correct version configured for java_home. I verified all of these aspects and couldn't find any of them alarming.
Java version -
qadeersmsiphone:main pdubey$ java -version
java version "1.8.0_51"
Java(TM) SE Runtime Environment (build 1.8.0_51-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.51-b03, mixed mode)
Maven Version -
qadeersmsiphone:main pdubey$ mvn -version
Apache Maven 3.1.1 (0728685237757ffbf44136acec0402957f723d9a; 2013-09-17 08:22:22-0700)
Maven home: /usr/share/maven
Java version: 1.8.0_51, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_51.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.8.5", arch: "x86_64", family: "mac"
and I checked that while building the project maven uses jdk 1.8
qadeersmsiphone:main pdubey$ mvn install -debug
Apache Maven 3.1.1 (0728685237757ffbf44136acec0402957f723d9a; 2013-09-17 08:22:22-0700)
Maven home: /usr/share/maven
Java version: 1.8.0_51, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_51.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.8.5", arch: "x86_64", family: "mac"
[INFO] Error stacktraces are turned on.
[DEBUG] Reading global settings from /usr/share/maven/conf/settings.xml
[DEBUG] Reading user settings from /Users/pdubey/.m2/settings.xml
[DEBUG] Using local repository at /Users/pdubey/.m2/repository
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10.0 for /Users/pdubey/.m2/repository
[INFO] Scanning for projects...
UPDATE: I could get it working by removing the
maven-compiler-plugin in pom file (Ideally, i don't want to do this). And i also observed that even if i
remove this plugin, maven by default downloads the 3.3 version of
compiler plugin in my local repo. I'm not sure what's wrong in this
plugin although source and target appears to be correct.

Check the java and Javac version - My Java version was 1.8.0_51
$ java -version
java version "1.8.0_51"
But javac version was pointing to old jdk 1.7.0_67
$ javac -version
javac 1.7.0_67
There are couple of thing which we should try -
Ensure that symbolic link is pointing to correct jdk. If not, remove existing link and create new one for your jdk
cd /System/Library/Frameworks/JavaVM.framework/Versions/
rm CurrentJDK
ln -s /Library/Java/JavaVirtualMachines/<jdk version>.jdk/Contents/ CurrentJDK
In /Library/Java/Extension, i had a tools.jar. I believe, this was from old jdk.
cd /Library/Java/Extensions
-rw-r--r-- 1 root admin 15286304 Jan 14 2015 tools.jar
Remove this
sudo rm -rf /Library/Java/Extensions
point 2 did the trick for me :)

Sometimes this problem is related to a JAVA_HOME used by maven.
In my particular case I tried to start an install target and had an exact the subj message.
Then I just tried an mvn -version command and I realized that it uses jdk7
Then I run in a console set JAVA_HOME=C:\Java\jdk8 (my jdk path, so your own could be different)
Then typed mvn clean install test and it worked just fine at last
Good luck!

Same issue here, but I was using run configurations inside Eclipse when maven kept throwing this error. Fixed by setting the right JDK version here:

I had the same issue:
> java -version
java version "1.8.0_111"
>javac -version
javac 1.7.0.6
I checked the Path in System variables, and the jdk was not updated to jdk 8.
After I updated the path with the right jdk it worked.

In cent os we can use alternatives to switch the version.
alternatives --config javac
alternatives --config java
But MAVEN uses JAVA_HOME.
And this JAVA_HOME can be possible to a link.
Either we have to point the JAVA_HOME manually to new jdk folder, OR manually remove/delete the link and create a new same link again from above answers.
From alternatives we can get the path of jdk

First of all, it is definitely versions issue.
In my situation:
java -version showed the result
java version "1.8.0_172"
and javac -version was showing
javac 1.8.0_172
BUT: Maven uses JAVA_HOME environment variable to get your JDK version to build a project and run it's a plugin. So the way how we have to check it is
echo %JAVA_HOME%
Which in my situation was
jdk1.7.0_172
So simply change the path to the variable will solve the issue.
Hope it will save time to someone.

How does maven know JAVA_HOME set as an environment variable inUbuntu

When I type mvn --version in ubuntu from the terminal(ubuntu),I get the below output.
Warning: JAVA_HOME environment variable is not set.
Apache Maven 3.0.5
Maven home: /usr/share/maven
Java version: 1.7.0_79, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-7-openjdk-amd64/jre
Default locale: en_IN, platform encoding: UTF-8
OS name: "linux", version: "3.13.0-32-generic", arch: "amd64", family: "unix"
When I did not set any JAVA_HOME environment variable , how is maven getting the java home installed path.Is it trying to find this path from the /usr/bin/java command which is installed in my system and if so why is it taking the path till jre.
P.S : Also I could not find any java path in any maven config.
Thanks.

As showed in the CLIReportingUtils.java (the maven class that retrieves the Java Home), the value comes from the following call :
System.getProperty( "java.home", "<unknown java home>" )
The java.home is for the JRE unlike the JAVA_HOME which is for the JDK.
So Maven is displaying the JRE home.

I would say there is a difference between JAVA_HOME environment variable and the output Java home: /usr/lib/jvm/java-7-openjdk-amd64/jre.
The latter is just the output of the installation directory see here.
So maven will run Java in background and java knows where its installed.

I think,I understand it now.In the maven script i.e (usr/share/maven/bin/mvn) they are trying to find the java installed using a variety of options.
So at one place they are doing the below
JAVACMD="`which java`"
And now in my system "which java" points to the below
java -> /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java
Hope this is how its getting the java path.

${java.home} changes when running Maven on a OS X

This appears to be a problem I do not see on linux or Windows machines. I have my environment setup with a JAVA_HOME derived from /usr/libexec/java_home. This is in my .bashrc file:
export JAVA_HOME=$(/usr/libexec/java_home -version 1.7)
which results in:
~/dev/Endeavor/endeavor-sdk$ echo $JAVA_HOME
/Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home
However when I run Maven on my project, I get an error from the native2ascii plugin:
[ERROR] Failed to execute goal org.codehaus.mojo:native2ascii-maven-plugin:1.0-alpha-2-SNAPSHOT:native2ascii (default) on project dataAccessServices: Error starting Sun's native2ascii: -> [Help 1]
My investigation points to that I am using a JRE instead of a JDK. That's odd since I am clearly pointing to the JDK in my JAVA_HOME variable. However, here is the output of mvn -version:
~/dev/Endeavor/endeavor-sdk$ mvn -version
Apache Maven 3.0.4 (r1232337; 2012-01-17 03:44:56-0500)
Maven home: /usr/share/maven
Java version: 1.7.0_17, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.7.0_17.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.7.5", arch: "x86_64", family: "mac"
Notice the "Java home:" line indicates that the ${java.home} variable has been moved to the JRE instead of the JDK that the JAVA_HOME environment variable points to.
I have tried setting the JAVA_HOME in numerous places but I can't seem to find a way to get maven to use the JDK as the home and not the JRE.
UPDATE:
I found this that appears to indicate that this is expected behavior: Java_home in Maven
But that does not explain why the native2ascii plugin cannot find the JDK tool it needs.
I have removed the use of native2ascii since it was largely unnecessary. So, I am avoiding the problem at this point. However, if anyone has an idea as to why this behaves differently on different systems, please let me know.

Have you tried running mvm help:system that should print all environment variable values that are relevant to maven?

There has been lots of discussions on this matter and here Java_home in Maven you can find a real good answer.
In a nutshell: your configuration it's just right, it is just a matter of semantics. You can read further here: http://javahowto.blogspot.com/2006/05/javahome-vs-javahome.html

Why isn't maven replacing the environment variable for the maven-release-plugin release version?

I am trying to use the maven-release-plugin with some environment variables, but I get an issue when I use an environment variable for the release version.
I am executing:
mvn release:clean --batch-mode -Dtag=${env.tag} -Dproject.rel.com.mycompany.project:project-root=${env.project.rel.com.mycompany.project:project-root} -Dproject.dev.com.mycompany.project:project-root=${env.project.dev.com.mycompany.project:project-root} release:prepare
I am getting:
[ERROR] Failed to execute goal
org.apache.maven.plugins:maven-release-plugin:2.4:prepare
(default-cli) on project project-root: Error parsing version,
cannot determine next version: Unable to parse the version string:
"${env.project.rel.com.mycompany.project:project-root}" -> [Help 1]
If I change the ${env.project.rel.com.mycompany.project:project-root} to a specific version, the command will pass.
But as you can see I am using:
${env.tag}
${env.project.dev.com.mycompany.project:project-root}
with no issues. Is this a bug? Or am I doing something wrong?
Additional notes:
Environment variables:
tag=2.55
project.rel.com.mycompany.project:project-root=2.55
project.dev.com.mycompany.project:project-root=2.56-SNAPSHOT
My Maven version is:
C:\>mvn -version
C:\>set MAVEN_OPTS=-Xmx1024m -XX:MaxPermSize=512m
Apache Maven 3.0.4 (r1232337; 2012-01-17 09:44:56+0100)
Maven home: C:\Users\John\Documents\apache-maven-3.0.4-bin
Java version: 1.6.0_25, vendor: Sun Microsystems Inc.
Java home: C:\JDK\jdk1.6.0_25\jre
Default locale: en_US, platform encoding: Cp1252
OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"

you will have to use the arguments attribute: http://maven.apache.org/maven-release/maven-release-plugin/prepare-mojo.html#arguments
So in your context your cmd line will look like this (Note the double quotes as well):
mvn release:clean --batch-mode release:prepare "-Darguments=-Dtag=${env.tag} -Dproject.rel.com.mycompany.project:project-root=${env.project.rel.com.mycompany.project:project-root} -Dproject.dev.com.mycompany.project:project-root=${env.project.dev.com.mycompany.project:project-root}"
Furthermore, if i remember right the uses of the tokens ${env.X} requires the usage of the property name in upper case (to be verified)

It's not working because the release plugin clears the environment[1]. I doubt it's documented[2], I found out by looking at the source. Farid's answer is a good workaround - it passes the environment value via java properties which are not cleared.
I would have simply commented on Farid's answer but SO doesn't think I'm shiny enough.
Why??
Classic maven.