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pom.xmlmaven-plugineclipse-neon

Maven and Eclipse integration

I have a few questions about Maven and Eclipse which I do not know much about them. I'm new to all these tools. Let me describe what I've done:

1 - installed apache-maven-3.3.9 on my window and placed at "C:\Program Files (x86)\apache-maven-3.3.9".

2 - Added MAVEN_HOME (and M2_HOME) environment variables.

3 - Added the "C:\Program Files (x86)\apache-maven-3.3.9\bin" to the Path environment variable.

4 - Set a proxy for Maven download by creating a xml file under ${user.home".m2]settings.xml. The content of the settings.xml is:

  <settings>
  <proxies>
    <proxy>
      <active>true</active>
      <protocol>https</protocol>
      <host>www.github.com</host>
      <port>8080</port>
      <nonProxyHosts>www.google.com</nonProxyHosts>
    </proxy>
  </proxies>
 </settings>

5 - Tested and see if the Maven was properly installed:

C:\>mvn --version
C:\
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5 2015-11-10T11:41:47-05:00)
Maven home: C:\Program Files (x86)\apache-maven-3.3.9
Java version: 1.8.0_101, vendor: Oracle Corporation
Java home: C:\Program Files (x86)\Java\jdk1.8.0_101\jrr
Default locale: en_US, platform encoding: Cp1252
OS name: "windows server 2008 r2", version: "6.1", arch: "x86", family: "dos"

6 - Tried to generate archetype and got a bunch of errors. Only one error is shown below. Basically, Maven tries to download the plugin but fails. I doubt the errors are caused by internet connection, but I don't know where else I need to look in order to fix this issue. The reason I said I doubted it was the internet connection issue is because I configure my POM file with the external jars on the web and all were downloaded correctly.

C:\>mvn archetype:generate
C:\
[INFO] Scanning for projects...
Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven
-clean-plugin/2.5/maven-clean-plugin-2.5.pom
[WARNING] Failed to retrieve plugin descriptor for   org.apache.maven.plugins:mave
n-clean-plugin:2.5: Plugin org.apache.maven.plugins:maven-clean-plugin:2.5 or on
e of its dependencies could not be resolved: Failed to read artifact descriptor
for org.apache.maven.plugins:maven-clean-plugin:jar:2.5
Downloading: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven
-install-plugin/2.4/maven-install-plugin-2.4.pom
Terminate batch job (Y/N)? y

C:\>

So... that is the maven plugins downloading problem.

And here is the Eclipse problem:

1 - Installed Eclipse Neon.

2 - Tried to add the Maven plugins and it say that all maven plugins already installed. I did the Maven plugins before with the previously installed Neon. Then I deleted the Neon Eclipse because it fails to create a simple Maven-archetype project. Then I re-installed the Neon Eclipse. But before I re-installed Eclipse I already deleted all previously-installed Eclipse folders but I do not know where the Eclipse keeps all of Maven info. When the newly-installed Eclipse tries to download the Maven plugins, it recognized that all of the Maven plugins were already installed. I have no ideas where Eclipse keeps all those info about Maven plugins?

3 - Tried again to create an simple Maven-archetype project, then I got this error message: Could not resolve archetype org.apache.maven.archetypes:maven-archetype-quickstart:1.1 from any of the configured repositories. Could not resolve artifact org.apache.maven.archetypes:maven-archetype-quickstart:pom:1.1 Could not transfer artifact org.apache.maven.archetypes:maven-archetype-quickstart:pom:1.1 from/to central (https://repo.maven.apache.org/maven2): connect timed out Could not transfer artifact org.apache.maven.archetypes:maven-archetype-quickstart:pom:1.1 from/to central (https://repo.maven.apache.org/maven2): connect timed out

So.. basically, it is the same error message that Maven has.

Questions:

1 - What are the things I need to do get Maven plugins download via command line?

2 - Similarly, what are the things I need to do to get Eclipse to create a simple maven-archetype project?

I did checked out all of questions and answers about the issues of Maven not being able to download the plugins. I did try everything in last several days but no prevail. I understand that the answers/solutions are good but they do not work for me. Maybe I need to other things that I don't know where else I need to look for?

3 - Let say that after all these efforts fail, can I manually download the Maven plugins and configure them via my POM.xml? I checked the apache Maven website and it seems that the answer is "yes" but it does not provide the "how". I know it is NOT the best solution for maven plugins download but if I couldn't fix the download issue, the I will have to resort to the manual download and then configure the POM file.

Would you please show me how to configure the POM.xml file with the Maven Plugins?

Sorry about the long questions, but I'm new to these tools and I'm just trying to get a simple Java project built by Maven via Eclipse.

Solution

  • The proxy in the settings file is for case where the machine you run is behind a proxy (lets say a corporate proxy). You have put github.com as the proxy host which is not right.

    If you have the maven installation bundled with eclipse that provides you integration with the IDE itself during the maven lifecycle process. You are however free to add a maven installation of your own by adding a existing maven installation from eclipse as well (you want to use a specific installation of maven with its settings).

    If you are behind a corporate proxy , you will have to get the proxy through which the machine connects to the internet. You can then add that detail into the proxy settings in maven. In the case that your corporate proxy uses a dynamic proxy (e.g. a .pac file opposed to static host) you will need to look at options like CNTLM or wagon to work around and get it running.