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Maven project only downloading from internal artifactory (pom.xml)

I have a local Java intelli-J project with a pom.xml that has (2) internal repositories on artifactory. The problem is I am doing some testing, and I think one of the JARs is not on this internal repo, so I want to use the regular Maven central repo. I googled and believe, the artifact should go through the list in your pom.xml is the order its listed and try to resolve the artifact, the problem is, even when I add the Maven central repo, it seems to never attempt; only tries the internal artifactory then fails.
In my pom.xml:
<repositories>
<repository>
<id>test</id>
<name>Maven Central</name>
<layout>default</layout>
<url>https://repo1.maven.org/maven2</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
<repository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>my_repo</id>
<name>MyRepo</name>
<url>https://myinternalrepo.com</url>
</repository>
<repository>
<snapshots />
<id>MySnapShotRepo</id>
<name>MyInternalRepo</name>
<url>https://myinternalreposnapshots.com</url>
</repository>
</repositories>
am I doing something wrong here?

I removed my settings.xml and was able to control the repositories from the pom.xml file tag. It also looks like maven repo is automatically tried whether you list it or not in pom .

Adding remote repository jar file as dependency in pom.xml maven

Is it possible to add remote repository jar file (https://repo.ah/lib/abc.jar) in maven pom.xml as dependency in java project. if so, can you please share example.

No, it's not possible to add a complete repository as a dependency. This doesn't make sense, because a repository can contain ten thousands of artifacts.
If your project requires artifacts which are not hosted in the standard remote repository, you can specify this via the <repositories> tag in your pom.xml .
<repositories>
<repository>
<id>vaadin-addons</id>
<url>http://maven.vaadin.com/vaadin-addons</url>
</repository>
<repository>
<id>vaadin-snapshots</id>
<url>http://oss.sonatype.org/content/repositories/vaadin-snapshots/</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>
More Informations:
Introduction to Repositories
Setting up Multiple Repositories

In the comments you mentioned that the URL is an Artifactory.
So just add the Artifactory as <repository> to your settings.xml and then you can use the jar in your application.

Maven refuse to download aar packaged dependency from remote repository

I want to use this android dependency in my java program:
http://jcenter.bintray.com/com/o3dr/android/dronekit-android/2.9.0/
so I added all the plugins & repositories into my maven pom file:
<repositories>
<repository>
<id>central</id>
<name>bintray</name>
<url>http://jcenter.bintray.com</url>
<!--<snapshots>-->
<!--<enabled>false</enabled>-->
<!--</snapshots>-->
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<!--<snapshots>-->
<!--<enabled>false</enabled>-->
<!--</snapshots>-->
<id>central</id>
<name>bintray-plugins</name>
<url>http://jcenter.bintray.com</url>
</pluginRepository>
</pluginRepositories>
<build>
<plugins>
<plugin>
<groupId>com.simpligility.maven.plugins</groupId>
<artifactId>android-maven-plugin</artifactId>
<version>4.1.0</version>
<extensions>true</extensions>
<configuration>
<sign>
<debug>false</debug>
</sign>
</configuration>
</plugin>
...
Then I add the dependency into the same file:
<dependency>
<groupId>com.o3dr.android</groupId>
<artifactId>dronekit-android</artifactId>
<version>2.9.0</version>
<type>aar</type>
</dependency>
But nothing happens, maven ignore it as if it doesn't exist, if I import its main package in a scala file and build it with mvn clear install -U, I get this error:
[ERROR] /home/peng/git-drone/dronespike/src/main/scala/Main.scala:1: object o3dr is not a member of package com
[ERROR] import com.o3dr.android._
[ERROR] ^
Question: What should I do to fix this problem?

Use Android packaging, e.g. <packaging>apk</packaging>.
If Maven couldn't download the artifact, it would complain much sooner in the build lifecycle. The problem is that artifact is downloaded, but not used. aar is not a standard Maven artifact, so Maven doesn't know what to do with it. Using it requires a third party plugin with extensions, hence usage of android-maven-plugin. Reading its documentation, it has some requirements to work properly. Specifically you didn't use android packaging as mentioned here:
usage of a supported packaging: apk, aar or apklib
Indeed, looking at the plugin source code it checks for android packaging before adding anything from aar to classpath.

Depending on the requirement from your maven version, based on what I faced before, you might have the need to add the configuration for release and snapshot. In my case, I was just able to get the lib once I specified these parameters:
<repositories>
<repository>
<id>central</id>
<name>bintray-plugins</name>
<url>http://jcenter.bintray.com</url>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>com.o3dr.android</groupId>
<artifactId>dronekit-android</artifactId>
<version>2.9.0</version>
<type>aar</type>
</dependency>
</dependencies>
without it, the dependency was not downloaded.

Looking at the bintray repository from where the dependency is available, and check the repository settings via its Set me up option, your repositories coordinates are not correct, they should instead be:
<repositories>
<repository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>bintray-3d-robotics-maven</id>
<name>bintray</name>
<url>http://dl.bintray.com/3d-robotics/maven</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<snapshots>
<enabled>false</enabled>
</snapshots>
<id>bintray-3d-robotics-maven</id>
<name>bintray-plugins</name>
<url>http://dl.bintray.com/3d-robotics/maven</url>
</pluginRepository>
</pluginRepositories>
And indeed the effective target file is available via the URL:
https://dl.bintray.com/3d-robotics/maven/com/o3dr/android/dronekit-android/2.9.0/
Which respects the repository URL plus its Maven coordinates (groupId, artifactId, version).
Also note: do not reuse the repository id central, unless for specific reason, otherwise you would override the central (default) repository of your Maven build and all of your dependencies (and plugins) would only be fetched by the newely declared one.

sbt-android can handle this configuration.
build.sbt
androidBuildJar
name := "yourproject"
organization := "yourorganization"
platformTarget := "android-24"
libraryDependencies +="com.o3dr.android" % "dronekit-android" % "2.9.0"
project/plugins.sbt
addSbtPlugin("org.scala-android" % "sbt-android" % "1.6.7")
Add publishing and resolver rules as necessary.

How can I make maven to use maven cetral repo?

So my default maven settings.xml file in my ~/.m2/ folder is containing links to my work repositories. So whenever I run an install on my pom.xml's it try to fetch from the corp nexus maven repositories.
For a hobby project which I am just starting with I don't want to make use of the corp maven nexus, but to make use of the central maven repo. I don't want to replace the entire settings.xml as this would mean reloading the entire local maven repo once I switch back to my corp work.
How can I achieve this ?

Add the following as your first repository in the repositories tag in the settings.xml
<repository>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
<id>central</id>
<url>http://repo1.maven.org/maven2</url>
</repository>
You may also want to use profiles. But, that is not a requirement.
You can also add a repository on your pom
<repositories>
<repository>
<id>central</id>
<url>http://rep1.maven.org/maven2</url>
</repository>
</repositories>

How can I prevent Maven from checking for updates from repositories that I don't list in my settings.xml file?

In my settings.xml file I have listed repositories that I want Maven to use (see the file below). These repositories are located in the build machine and I am working this way to prevent a build fail when there's is no Internet connection in the build machine.
The problem is that Maven automatically looks for updates in the central repository (and possibly from other non-listed repositories) during the build. Is there a way to prevent this behaviour?
...
<profile>
<id>myProfile</id>
<repositories>
<repository>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
<snapshots>
<updatePolicy>never</updatePolicy>
</snapshots>
<id>myRepo</id>
<url>file://${my.home}/maven/.m2/repository</url>
<layout>default</layout>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
<snapshots>
<updatePolicy>never</updatePolicy>
</snapshots>
<id>myRepo</id>
<url>file://${my.home}/maven/.m2/repository</url>
<layout>default</layout>
</pluginRepository>
</pluginRepositories>
</profile>
...
Note: Using the offline option (e.g. -o flag) is not an option for me. What I really want is Maven to use only the repositories that I list in my settings.xml file.

Every Maven project inherits the configuration for the central repository from the Maven Super POM. You can use Maven's mirrors feature to redirect calls to central to your preferred repository. You do this by adding some configuration to your settings.xml like this:
<settings>
...
<mirrors>
<mirror>
<id>central-proxy</id>
<mirrorOf>central</mirrorOf>
<url>http://myrepository/releases</url>
</mirror>
</mirrors>
..
</settings>
This configuration can either be put in your user settings (${user.home}/.m2/settings.xml) or global settings ({$M2_HOME}/conf/settings.xml).

Set your desired repositories as a mirror of everything else.
More details: http://maven.apache.org/guides/mini/guide-mirror-settings.html