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I cannot compile my javafx maven project on Raspberry pi

I created a java project which compiles and runs fine on my mac with "mvn compile". But once I fetch it from gitlab on my Pi it won't compile on linux.
I consulted many pages but none seem to apply to this particular issue.
Can anyone help me? I would be really grateful!
The error:
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< SmartMirror:SmartMirror >-----------------------
[INFO] Building SmartMirror 0.0.1-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.816 s
[INFO] Finished at: 2022-07-23T14:54:44+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal on project SmartMirror: Could not resolve dependencies for project SmartMirror:SmartMirror:jar:0.0.1-SNAPSHOT: The following artifacts could not be resolved: org.openjfx:javafx-controls:jar:${javafx.platform}:19-ea+9, org.openjfx:javafx-graphics:jar:${javafx.platform}:19-ea+9, org.openjfx:javafx-base:jar:${javafx.platform}:19-ea+9, org.openjfx:javafx-fxml:jar:${javafx.platform}:19-ea+9: Failure to find org.openjfx:javafx-controls:jar:${javafx.platform}:19-ea+9 in https://repo.maven.apache.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced -> [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] http://cwiki.apache.org/confluence/display/MAVEN/DependencyResolutionException
The POM.xml file:
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>SmartMirror</groupId>
<artifactId>SmartMirror</artifactId>
<version>0.0.1-SNAPSHOT</version>
<properties>
<mainClass>main.Main</mainClass>
<maven.compiler.source>1.9</maven.compiler.source>
<maven.compiler.target>1.9</maven.compiler.target>
<javafx.platform>linux</javafx.platform>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.3.0</version>
<executions>
<execution>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<shadedArtifactAttached>true</shadedArtifactAttached>
<transformers>
<transformer
implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>main.Main</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.10.1</version>
</plugin>
<plugin>
<groupId>org.openjfx</groupId>
<artifactId>javafx-maven-plugin</artifactId>
<version>0.0.8</version>
<configuration>
<mainClass>Main</mainClass>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.openjfx/javafx-controls -->
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-controls</artifactId>
<version>19-ea+9</version>
<classifier>linux</classifier>
</dependency>
<!-- https://mvnrepository.com/artifact/org.openjfx/javafx-fxml -->
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-fxml</artifactId>
<version>19-ea+9</version>
<classifier>linux</classifier>
</dependency>
<dependency>
<groupId>com.mashape.unirest</groupId>
<artifactId>unirest-java</artifactId>
<version>1.4.9</version>
</dependency>
</dependencies>
</project>
The module-info.java file:
module SmartMirror {
exports weather to javafx.graphics, javafx.fxml;
exports main to javafx.graphics, javafx.fxml;
opens weather to javafx.graphics, javafx.fxml;
opens main to javafx.graphics, javafx.fxml;
requires javafx.base;
requires javafx.controls;
requires javafx.fxml;
requires transitive javafx.graphics;
requires transitive json;
}
Edit:
Thank you so far for your answers. Though the issue persists. Any more ideas?

I used this command on Raspberry Pi 3B (Raspberry Pi OS lite 32bit) :
mvn -Djavafx.platform=linux-arm32-monocle clean compile
if you use 64bit version :
mvn -Djavafx.platform=linux-aarch64-monocle clean compile

Uploading in heroku error. Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile. Uploading Heroku with git in spring

The Full error is:
Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project DAI: Fatal error compiling: invalid target release: 11 -> [Help 1]
Im using git to put into the git that is provided
Full error part in cmd:
remote: [INFO] ------------------------------------------------------------------------
remote: [INFO] BUILD FAILURE
remote: [INFO] ------------------------------------------------------------------------
remote: [INFO] Total time: 23.195 s
remote: [INFO] Finished at: 2022-04-25T13:37:56Z
remote: [INFO] ------------------------------------------------------------------------
remote: [ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project DAI: Fatal error compiling: invalid target release: 11 -> [Help 1]
remote: [ERROR]
remote: [ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
remote: [ERROR] Re-run Maven using the -X switch to enable full debug logging.
remote: [ERROR]
remote: [ERROR] For more information about the errors and possible solutions, please read the following articles:
remote: [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
remote:
remote: ! ERROR: Failed to build app with Maven
remote: We're sorry this build is failing! If you can't find the issue in application code,
remote: please submit a ticket so we can help: https://help.heroku.com/
remote:
remote: ! Push rejected, failed to compile Java app.
remote:
remote: ! Push failed
remote: !
remote: ! ## Warning - The same version of this code has already been built: 7443754b101ae5df5488e13d965acefaa6099876
remote: !
remote: ! We have detected that you have triggered a build from source code with version 7443754b101ae5df5488e13d965acefaa6099876
remote: ! at least twice. One common cause of this behavior is attempting to deploy code from a different branch.
remote: !
remote: ! If you are developing on a branch and deploying via git you must run:
remote: !
remote: ! git push heroku <branchname>:main
remote: !
remote: ! This article goes into details on the behavior:
remote: ! https://devcenter.heroku.com/articles/duplicate-build-version
remote:
remote: Verifying deploy...
remote:
remote: ! Push rejected to still-dusk-73288.
remote:
To https://git.heroku.com/still-dusk-73288.git
! [remote rejected] main -> main (pre-receive hook declined)
error: failed to push some refs to 'git repo'
My full pom.xml file:
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.4</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>DAI</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>DAI</name>
<description>Projecto de DAI</description>
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<!--<java.version>11</java.version>-->
<repackage.classifier/>
<spring-native.version>0.11.3</spring-native.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.apache.sshd</groupId>
<artifactId>sshd-core</artifactId>
<version>2.5.1</version>
</dependency>
<!--<dependency>
<groupId>org.springframework.experimental</groupId>
<artifactId>spring-native</artifactId>
<version>${spring-native.version}</version>
</dependency>-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.44</version>
<scope>runtime</scope>
</dependency>
<!--<dependency>
<groupId>org.springframework.boot</groupId>ng-boot-starter-t
<artifactId>spriest</artifactId>
<scope>test</scope>
</dependency>-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>5.8.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-test</artifactId>
<version>2.6.4</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot</artifactId>
<version>2.6.4</version>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-launcher</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.19</version>
</dependency>
<!--<dependency>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
<scope>test</scope>
</dependency>-->
<!-- <dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>-->
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<classifier>${repackage.classifier}</classifier>
<image>
<builder>paketobuildpacks/builder:tiny</builder>
<env>
<BP_NATIVE_IMAGE>true</BP_NATIVE_IMAGE>
</env>
</image>
</configuration>
</plugin>
<plugin>
<groupId>com.heroku.sdk</groupId>
<artifactId>heroku-maven-plugin</artifactId>
<version>3.0.3</version>
</plugin>
<!--<plugin>
<groupId>org.springframework.experimental</groupId>
<artifactId>spring-aot-maven-plugin</artifactId>
<version>${spring-native.version}</version>
<executions>
<execution>
<id>test-generate</id>
<goals>
<goal>test-generate</goal>
</goals>
</execution>
<execution>
<id>generate</id>
<goals>
<goal>generate</goal>
</goals>
</execution>
</executions>
</plugin>-->
<plugin>
<groupId>org.hibernate.orm.tooling</groupId>
<artifactId>hibernate-enhance-maven-plugin</artifactId>
<version>${hibernate.version}</version>
<executions>
<execution>
<id>enhance</id>
<goals>
<goal>enhance</goal>
</goals>
<configuration>
<failOnError>true</failOnError>
<enableLazyInitialization>true</enableLazyInitialization>
<enableDirtyTracking>true</enableDirtyTracking>
<enableAssociationManagement>true</enableAssociationManagement>
<enableExtendedEnhancement>false</enableExtendedEnhancement>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<fork>true</fork>
<source>17</source>
<target>17</target>
</configuration>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>
<profiles>
<profile>
<id>native</id>
<properties>
<repackage.classifier>exec</repackage.classifier>
<native-buildtools.version>0.9.10</native-buildtools.version>
</properties>
<!--<dependencies>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-launcher</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.graalvm.buildtools</groupId>
<artifactId>native-maven-plugin</artifactId>
<version>${native-buildtools.version}</version>
<extensions>true</extensions>
<executions>
<execution>
<id>test-native</id>
<phase>test</phase>
<goals>
<goal>test</goal>
</goals>
</execution>
<execution>
<id>build-native</id>
<phase>package</phase>
<goals>
<goal>build</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>-->
</profile>
</profiles>
</project>
I already tried some solutions for the problem in stack overflow. But at the moment nothing resulted.
Can someone give some solutions to try to put in heroku? I need to put one api online as fast as possible. Thanks in advance :)

This is probably just a problem in version because heroku run by default version:
java: 8 & jdk: 1.8
you can change your project version and will work fine,
otherwise you can create a file system.properties in your root directory, and define the version you work with java.runtime.version, you can find the details here: https://devcenter.heroku.com/articles/java-support

Maybe its answer is a little bit late, i met the same problem like yours. but i changed my <java.version>17</java.version>to <java.version>1.8</java.version>. and it can be run.
if someone has the same problem, you can try this.

Maven build failure classNotFoundException

It's my first time trying out maven and I can't understand why I keep getting classnotfoundexception every time I am trying to build. This is the error I am receiving:
[INFO] Scanning for projects...
[INFO]
[INFO] ---------------------------< owmapi:owmapi >----------------------------
[INFO] Building OwmAPICase 0.0.1-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- exec-maven-plugin:3.0.0:java (default-cli) # owmapi ---
[WARNING]
java.lang.ClassNotFoundException: owmapi.Main
at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:435)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:589)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:246)
at java.base/java.lang.Thread.run(Thread.java:832)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.582 s
[INFO] Finished at: 2021-02-28T14:09:17+01:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:3.0.0:java (default-cli) on project owmapi: An exception occured while executing the Java class. owmapi.Main -> [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] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
And this is my pom.xml:
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>owmapi</groupId> <!-- case.se.ctk -->
<artifactId>owmapi</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>OwmAPICase</name>
<properties>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<mainClass>owmapi.Main</mainClass>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/net.aksingh/owm-japis -->
<dependency>
<groupId>net.aksingh</groupId>
<artifactId>owm-japis</artifactId>
<version>2.5.3.0</version>
</dependency>
</dependencies>
</project>
Everything works fine if i simply run the project as a java application in eclipse but for some reason it won't work with maven. I guess the problem lies in mainClass in my pom but I've tried several solutions to no avail.

I think your main class have some dependencies on the jar mentioned in the pom.xml. You're simply creating a target jar which doesn't have those dependencies included. You need to create the uber/fat jar which include all the relevant dependencies. You can use this following plugin maven-assembly-plugin for creating the target jar.
Assumption: Main.java class is under package owmapi.
<build>
<finalName>owmapi</finalName>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>owmapi.Main</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
</build>

Connection time out, Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved

I am getting below error while doing mvn insatll. I did almost everything to resolve it like:Force Update,I deleted the /.m2 folder as well.Not using any Proxy as well, also checked the /user/.m2/settings.xml file. What else I could do please help? I have also added my POM.xml file below.
Error:
[INFO] --------------------------------[ war ]---------------------------------
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/maven-resources-plugin-2.6.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 28.775 s
[INFO] Finished at: 2020-05-22T18:36:39+05:30
[INFO] ------------------------------------------------------------------------
[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6: Could not transfer artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (https://repo.maven.apache.org/maven2): Transfer failed for https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/maven-resources-plugin-2.6.pom ProxyInfo{host='172.19.217.26', userName='null', port=8080, type='https', nonProxyHosts='null'}: Connect to 172.19.217.26:8080 [/172.19.217.26] failed: Connection timed out: connect -> [Help 1]
[ERROR]
Pom.xml
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.aman.emi</groupId>
<artifactId>Dev-portlet</artifactId>
<packaging>war</packaging>
<name>productionstatus-portlet</name>
<version>1.0</version>
<properties>
<faces.api.version>2.2</faces.api.version>
<liferay.faces.bridge.ext.version>5.0.0</liferay.faces.bridge.ext.version>
<liferay.faces.bridge.version>4.0.0</liferay.faces.bridge.version>
<mojarra.version>2.2.13</mojarra.version>
</properties>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.3</version>
<configuration>
<encoding>UTF-8</encoding>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.3</version>
<configuration>
<filteringDeploymentDescriptors>true</filteringDeploymentDescriptors>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<!-- https://mvnrepository.com/artifact/oracle/ojdbc6 -->
<!-- <dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.22</version>
</dependency> -->
<!-- https://mvnrepository.com/artifact/com.github.noraui/ojdbc7 -->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
<optional>true</optional>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
<optional>true</optional>
</dependency>
</dependencies>
</project>

Could not find goal 'devmode' in plugin org.codehaus.mojo

I am a beginner in GWT and Maven. I created a new GWT Application project in Eclipse. Then, I converted that project into Maven Project by right-click on Project name => Configure => Convert to Maven Project and I saw that a pom file was generated for that project. Next, I run as project as Maven build but it was not compiled since a goal was not specified there. Actually, I don't understand what exactly have I to write under that goal section, therefore, I wrote package under that and then again I built maven and it compiled successfully.
After that, I tried to run this maven project in Command Prompt on the SuperDevMode using the 2nd step mentioned on Run the GWT Project under the Setting up a new project section. But while following these steps on Command Prompt, I got an error that devmode could not be found. Here is my Command prompt log:
C:\Users\TEST>cd eclipse-workspace/MyWebApp
C:\Users\TEST\eclipse-workspace\MyWebApp>mvn war:exploded
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building MavenApp 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-war-plugin:3.1.0:exploded (default-cli) # abcdef ---
[INFO] Exploding webapp
[INFO] Assembling webapp [abcdef] in [C:\Users\TEST\eclipse-workspace\MyWebApp\target\abcdef-0.0.1-SNAPSHOT]
[INFO] Processing war project
[INFO] Webapp assembled in [63 msecs]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.920 s
[INFO] Finished at: 2017-08-30T11:24:53+05:30
[INFO] Final Memory: 12M/107M
[INFO] ------------------------------------------------------------------------
C:\Users\TEST\eclipse-workspace\MyWebApp>mvn gwt:devmode
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.301 s
[INFO] Finished at: 2017-08-30T11:25:02+05:30
[INFO] Final Memory: 8M/107M
[INFO] ------------------------------------------------------------------------
[ERROR] Could not find goal 'devmode' in plugin org.codehaus.mojo:gwt-maven-plugin:2.8.1 among available goals clean, compile, compile-report, css, debug, eclipse, eclipseTest, generateAsync, help, i18n, mergewebxml, resources, run, run-codeserver, source-jar, test -> [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] http://cwiki.apache.org/confluence/display/MAVEN/MojoNotFoundException
Here is my pom.xml file:
<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>MyWebApp</groupId>
<artifactId>abcdef</artifactId>
<version>0.0.1-SNAPSHOT</version>
<build>
<sourceDirectory>src</sourceDirectory>
<testSourceDirectory>test</testSourceDirectory>
<resources>
<resource>
<directory>src</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</resource>
</resources>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
<name>MavenApp</name>
<description>It is a maven app</description>
</project>
I searched a lot to resolve this error but found no solution for that issue. Please help me to fix this issue as I am very confused on how to fix it.
Edit: After further study, I used mvn gwt:run as an alternative to the command mvn gwt:devmode, but still I got another error on command prompt as given below:
[ERROR] Failed to execute goal org.codehaus.mojo:gwt-maven-plugin:2.8.1:run (default-cli) on project MyWebApp: The parameters 'runTarget' for goal org.codehaus.mojo:gwt-maven-plugin:2.8.1:run are missing or invalid

Without any more information than gwt:devmode, Maven will try to find an appropriate plugin, based on its default settings. It happens that a gwt-maven-plugin exists with org.codehaus.mojo as groupId, fitting in Maven built-in plugin resolution.
But this is not the plugin you're looking for.
You are probably trying to use this one, so just add this to your pom.xml, in the <plugins> section:
<plugin>
<groupId>net.ltgt.gwt.maven</groupId>
<artifactId>gwt-maven-plugin</artifactId>
<version>1.0-rc-8</version>
<extensions>true</extensions>
<configuration>
<moduleName>com.example.app.App</moduleName>
</configuration>
</plugin>
Adapting the moduleName if needed.

Well, I was able to solve this issue by copying some dependencies, plugin, and configuration from the pom.xml file (which is generated in the project created by the webAppCreator using maven) to the pom.xml file of my project created in the Eclipse. So, this is my pom.xml file created finally:
<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>MyPersonalProject</groupId>
<artifactId>MyPersonalProject</artifactId>
<version>0.0.1-SNAPSHOT</version>
<properties>
<!-- Setting maven.compiler.source to something different to 1.8
needs that you configure the sourceLevel in gwt-maven-plugin since
GWT compiler 2.8 requires 1.8 (see gwt-maven-plugin block below) -->
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<!-- Don't let your Mac use a crazy non-standard encoding -->
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
</properties>
<dependencyManagement>
<dependencies>
<!-- ensure all GWT deps use the same version (unless overridden) -->
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt</artifactId>
<version>2.8.1</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-servlet</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-user</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-dev</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<outputDirectory>${project.build.directory}/${project.build.finalName}/WEB-INF/classes</outputDirectory>
<sourceDirectory>src</sourceDirectory>
<testSourceDirectory>test</testSourceDirectory>
<resources>
<resource>
<directory>src</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</resource>
</resources>
<plugins>
<plugin>
<groupId>net.ltgt.gwt.maven</groupId>
<artifactId>gwt-maven-plugin</artifactId>
<version>1.0-rc-6</version>
<executions>
<execution>
<goals>
<goal>import-sources</goal>
<goal>compile</goal>
<goal>import-test-sources</goal>
<goal>test</goal>
</goals>
</execution>
</executions>
<configuration>
<moduleName>mypackage.MyPersonalproject</moduleName>
<failOnError>true</failOnError>
<!-- GWT compiler 2.8 requires 1.8, hence define sourceLevel here if you use
a different source language for java compilation -->
<sourceLevel>1.8</sourceLevel>
<!-- Compiler configuration -->
<compilerArgs>
<!-- Ask GWT to create the Story of Your Compile (SOYC) (gwt:compile) -->
<arg>-compileReport</arg>
<arg>-XcompilerMetrics</arg>
</compilerArgs>
<!-- DevMode configuration -->
<warDir>${project.build.directory}/${project.build.finalName}</warDir>
<classpathScope>compile+runtime</classpathScope>
<!-- URL(s) that should be opened by DevMode (gwt:devmode). -->
<startupUrls>
<startupUrl>MyPersonalProject.html</startupUrl>
</startupUrls>
</configuration>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
When I run this application using maven in the Command Prompt, it ran successfully except showing 2 or 3 warnings in the Command Prompt log. Also, I noticed that the SNAPSHOT generated in the version is different for the pom.xml created by Eclipse as compared to the one created by the maven project on command prompt.