installing maven 2.2.1 in eclipse JUNO?

I am new in java please help me how to install maven 2.2.1 in eclipse JUNO?

Solution

Go to this page (this is official maven download page). Choose version that you want to install. Install it. If you use Windows extract files in C drive. Then go to System Properties->Advanced->Environment Variables and add there MAVEN_HOME variable with path like this D:\Java\apache-maven-3.0.4 than add into PATH variable this %MAVEN_HOME%\bin;. This help to install maven on your machine. Then as say @Joe2013 Go to Eclipse-->Help-->Eclipse Market Place and write maven and you will sea Maven Integration Plugin. Install it and you configured eclipse with maven)

UPDATE for your second question

may be you forget to add to your pom.xml this:

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>com.maventest.App</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>