Required class is missing: org/codehaus/gmaven/mojo/GroovyMojo when tried to run to generate report and send an email in the Maven Project - eclipse

Question

I have Maven JUnit Project, which compiles, builds and tests successfully. Also when I do the mvn site all the tests run successfully and generates the surefire-report at ..\target\site.. directory.
Now, I need to send an email this report to given recipients.
Here is my POM:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>xxxx</groupId>
<artifactId>EmailReportMaven</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name></name>
<description></description>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.18.1</version>
</dependency>
<dependency>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-site-plugin</artifactId>
<version>3.6</version>
</dependency>
<dependency>
<groupId>org.apache.maven.doxia</groupId>
<artifactId>doxia-core</artifactId>
<version>1.7</version>
</dependency>
<dependency>
<groupId>ch.fortysix</groupId>
<artifactId>maven-postman-plugin</artifactId>
<version>0.1.6</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<version>1.10</version>
<executions>
<execution>
<id>add-source</id>
<phase>generate-sources</phase>
<goals>
<goal>add-source</goal>
</goals>
<configuration>
<sources>
<source>appmodels</source>
</sources>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<testFailureIgnore>false</testFailureIgnore>
</configuration>
<version>2.7.2</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.18.1</version>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-site-plugin</artifactId>
<version>3.6</version>
<configuration>
<generateSitemap>true</generateSitemap>
<generateReports>true</generateReports>
</configuration>
</plugin>
<plugin>
<groupId>ch.fortysix</groupId>
<artifactId>maven-postman-plugin</artifactId>
<version>0.1.6</version>
<executions>
<execution>
<id>send_an_mail</id>
<goals>
<goal>send-mail</goal>
</goals>
<inherited>false</inherited>
<phase>test</phase>
<configuration>
<from>mailID</from>
<subject>this is a test auto email sent from Eclipse using Maven</subject>
<htmlMessage><![CDATA[<p>Hi, Please find attached.</p>]]></htmlMessage>
<failonerror>true</failonerror>
<mailhost>host</mailhost>
<mailport>port</mailport>
<mailssl>true</mailssl>
<mailAltConfig>true</mailAltConfig>
<mailuser>emailID</mailuser>
<mailpassword>password</mailpassword>
<receivers>
<receiver>emailID</receiver>
</receivers>
<fileSets>
<fileSet>
<directory>${basedir}/target/site</directory>
<includes>
<include>**/surefire-report.html</include>
</includes>
</fileSet>
</fileSets>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
<plugin>
<groupId>org.eclipse.m2e</groupId>
<artifactId>lifecycle-mapping</artifactId>
<version>1.0.0</version>
<configuration>
<lifecycleMappingMetadata>
<pluginExecutions>
<pluginExecution>
<pluginExecutionFilter>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<versionRange>[1.10,)</versionRange>
<goals>
<goal>add-source</goal>
</goals>
</pluginExecutionFilter>
<action>
<ignore />
</action>
</pluginExecution>
</pluginExecutions>
</lifecycleMappingMetadata>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
<reporting>
<plugins>
<!-- Include the unit test reports in the site -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<version>2.18.1</version>
</plugin>
</plugins>
Below errors are thrown when mvn surefire-report:report postman:send-mail is run:
[INFO] --- maven-postman-plugin:0.1.6:send-mail (Report Generation) # EmailReportMaven ---
[WARNING] Error injecting: ch.fortysix.maven.plugin.postaman.MailSenderMojo
java.lang.TypeNotPresentException: Type
ch.fortysix.maven.plugin.postaman.MailSenderMojo not present
at org.eclipse.sisu.space.URLClassSpace.loadClass(URLClassSpace.java:147)
at org.eclipse.sisu.space.NamedClass.load(NamedClass.java:46)
at org.eclipse.sisu.space.AbstractDeferredClass.get(AbstractDeferredClass.java:48)
at com.google.inject.internal.ProviderInternalFactory.provision(ProviderInternalFactory.java:81)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.provision(InternalFactoryToInitializableAdapter.java:53)
at com.google.inject.internal.ProviderInternalFactory$1.call(ProviderInternalFactory.java:65)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:115)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:133)
at com.google.inject.internal.ProvisionListenerStackCallback.provision(ProvisionListenerStackCallback.java:68)
at com.google.inject.internal.ProviderInternalFactory.circularGet(ProviderInternalFactory.java:63)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.get(InternalFactoryToInitializableAdapter.java:45)
at com.google.inject.internal.InjectorImpl$2$1.call(InjectorImpl.java:1016)
at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1092)
at com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1012)
at org.eclipse.sisu.inject.Guice4$1.get(Guice4.java:162)
at org.eclipse.sisu.inject.LazyBeanEntry.getValue(LazyBeanEntry.java:81)
at org.eclipse.sisu.plexus.LazyPlexusBean.getValue(LazyPlexusBean.java:51)
at org.codehaus.plexus.DefaultPlexusContainer.lookup(DefaultPlexusContainer.java:263)
at org.codehaus.plexus.DefaultPlexusContainer.lookup(DefaultPlexusContainer.java:255)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getConfiguredMojo(DefaultMavenPluginManager.java:519)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:121)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:154)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:146)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:309)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:194)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:107)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:993)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:345)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:191)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: java.lang.NoClassDefFoundError: org/codehaus/gmaven/mojo/GroovyMojo
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(ClassRealm.java:401)
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:42)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(ClassRealm.java:401)
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:42)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
at org.eclipse.sisu.space.URLClassSpace.loadClass(URLClassSpace.java:139)
... 41 more
Caused by: java.lang.ClassNotFoundException: org.codehaus.gmaven.mojo.GroovyMojo
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
... 70 more
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 24.073 s [INFO] Finished at:
2017-07-05T18:47:50-05:00 [INFO] Final Memory: 28M/226M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal
ch.fortysix:maven-postman-plugin:0.1.6:send-mail (Report Generation)
on project EmailReportMaven: Execution Report Generation of goal
ch.fortysix:maven-postman-plugin:0.1.6:send-mail failed: Unable to
load the mojo 'send-mail' in the plugin
'ch.fortysix:maven-postman-plugin:0.1.6'. A required class is missing:
org/codehaus/gmaven/mojo/GroovyMojo
[ERROR] -----------------------------------------------------
[ERROR] realm = plugin>ch.fortysix:maven-postman-plugin:0.1.6
[ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
[ERROR] urls[0] =
file:/C:/Development/Maven_Repo/ch/fortysix/maven-postman-plugin/0.1.6/maven-postman-plugin-0.1.6.jar
[ERROR] urls[1] =
file:/C:/Development/Maven_Repo/org/codehaus/plexus/plexus-utils/1.1/plexus-utils-1.1.jar
[ERROR] Number of foreign imports: 1
[ERROR] import: Entry[import from realm ClassRealm[maven.api, parent: null]]
[ERROR]
[ERROR] -----------------------------------------------------
[ERROR] : org.codehaus.gmaven.mojo.GroovyMojo
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1]

Answer 1

I was able to resolve this issue. I did the following things:
Deleted the contents of the ../org/apache/maven folder.
Deleted the contents of the ../ch/ folder (this was the turning point, I thought so)
Re-built the Maven project.
Ran mvn site command.
Successfully e-mail sent with surefire-report.html as attachment.