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Maven version and java version conflict

I can only use java 1.6 for my project. So maven version also has to be 2.2.1 . Cannot use maven 3.0. But while building I'm getting following error :
Error resolving version for 'org.apache.maven.plugins:maven-jar-plugin':Plugin requires Maven version 3.0
this is the pom:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
what are the version that we can use?

Changes the source and target to 1.6. If your code does not make use of java8 features then it should work just fine. This will generate a jar that is compatible with any java6 codebase.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>

compile java source 1.7 for 1.6 with Maven and Netbeans

I have a source code written for java 1.7. I would like to compile it for java 1.6. If I understood correctly, I need to use the options -source 1.7 -target 1.6
I am using Maven2 and Netbeans (8.0). So, I tried :
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.2</version>
<configuration>
<source>1.7</source>
<target>1.6</target>
<compilerArguments>
<bootclasspath>/usr/lib/jvm/java-6-openjdk-amd64/jre/lib/rt.jar</bootclasspath>
</compilerArguments>
</configuration>
</plugin>
But I get a javacTask: source release 1.7 requires target release 1.7
I read that some people use eclipse compiler to make it work, but how can I do this if I'm using Netbeans ?
Thanks a lot for your help

EDIT Sorry it's the other way around. You can compile source 1.6 and target 1.7 but you can't compile it when source version > target version because then it couldn't handle new features of the language.
For more detail about this see Cross-Compilation Options in javac documentation http://docs.oracle.com/javase/7/docs/technotes/tools/windows/javac.html.
If you would have 1.6 sources you could compile them for target version 1.7 like this:
<project>
[...]
<build>
[...]
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.2</version>
<configuration>
<source>1.6</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
[...]
</build>
[...]
</project>>

how to know maven compiler version ?is this same as maven installation i.e-apache-maven-3.1.1

in pom.xml <plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<configuration>
<source>${jdk.version}</source>
<target>${jdk.version}</target>
</configuration>
</plugin> what should be the version no?,i mean from where i will get this version no?
is this the same i.e mvn installation .

See http://maven.apache.org/plugins/maven-compiler-plugin/compile-mojo.html#source
Although the values are not explicitly defined, it follows the convention of major Java releases - 1.5, 1.6, 1.7, 1.8, etc.

Using not-default compilier for maven project

I have two JDK - 1.5 and 1.6.
Default JDK is 1.6 (JAVA_HOME sets to JDK 1.6)
and have env. variable JAVA_HOME_1_5 sets to JDK 1.5
I want compile maven project with JDK 1.5, so I added to pom.xml next:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<fork>true</fork>
<executable>${env.JAVA_HOME_1_5}/bin/javac.exe</executable>
<showDeprecation>true</showDeprecation>
<showWarnings>true</showWarnings>
<optimize>true</optimize>
<source>1.5</source>
<target>1.5</target>
</configuration>
</plugin>
But maven is compiling my project with JDK 1.6!
What is wrong?
Thanks in advance!

%> JAVA_HOME=$JAVA_HOME_1_5 mvn install
Maven by default use JAVA_HOME so you can set it to jdk_1.5 just for it.
For pom way, you should add this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<jvm>${JAVA_HOME_1_5}/bin/java</jvm>
<forkMode>once</forkMode>
</configuration>
</plugin>

Could it be because, as documented here, you are missing the <compilerVersion>1.5</compilerVersion> in your configuration?

can you try this. It works for me.
http://maven.apache.org/plugins/maven-compiler-plugin/examples/compile-using-different-jdk.html

Using different Java source version when running Maven2 build

I'm attempting to run my Maven build using the usual:
mvn clean install
I'm getting a whole series of errors that read:
annotations are not supported in -source 1.3
(use -source 5 or higher to enable annotations)
How do I use -source 5 when performing the build. My JAVA_HOME is pointing to JDK 1.6.

Add this to your pom.xml:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
It is also documented in the Maven FAQ.
For further information take a look at the Compiler Plugin documentation.

it's in the pom.xml. you should have <source>1.3</source> change it to
<source>1.6</source>