Develop Reference

Share common configuration between different plugins in the same Maven module

I'm working on a Maven project which uses both the Surefire and Failsafe plugins in the same module. The configurations for both plugins are pretty much identical, except for one element (classpathDependencyExcludes), as you can see.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>3.0.0-M4</version>
<configuration>
<skipTests>${skipTests}</skipTests>
<forkCount>1</forkCount>
<reuseForks>false</reuseForks>
<argLine>-javaagent:"${project.build.directory}/openejb-javaagent-${tomee.version}.jar"</argLine>
<workingDirectory>${project.build.directory}</workingDirectory>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-failsafe-plugin</artifactId>
<version>3.0.0-M4</version>
<configuration>
<skipTests>${skipTests}</skipTests>
<forkCount>1</forkCount>
<reuseForks>false</reuseForks>
<argLine>-javaagent:"${project.build.directory}/openejb-javaagent-${tomee.version}.jar"</argLine>
<workingDirectory>${project.build.directory}</workingDirectory>
<classpathDependencyExcludes>
<classpathDependencyExclude>javax:javaee-api</classpathDependencyExclude>
</classpathDependencyExcludes>
</configuration>
</plugin>
I was wondering if there was a way to share the common section of the configuration between the two plugins by writing it down once instead of multiple times. If not, in the hypothesis that both configurations were identical, would it be possible?

First of all, you don't need to set all the properties explicitly. skipTests has already the value of ${skipTests}, no need to repeat that. forkCount has already the default value 1.
Some of the other properties can be set in the <properties> section, like reuseForks and argLine.
Then there is very little left to worry about.

Java / mvn code coverage AND redundancy?

Have a monolthic app that runs JUnit tests through Surefire and Maven. I see several options out there that will tell me about code coverage, but I'm trying to find something a little different:
Specifically, I'd like to run a mvn build that generates a report (or use an Eclipse plugin that does the same) that will give me a way to see what tests are all pretty much doing the same thing, in addition to the parts of the app that do not have good coverage. Does something like this exist?

I doesn't cover the redundancy part, but for the coverage you may use Jacoco, it's easy to setup with maven:
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-site-plugin</artifactId>
<version>3.6</version>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>0.7.7.201606060606</version>
<executions>
<execution>
<id>default-prepare-agent</id>
<goals>
<goal>prepare-agent</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
<reporting>
<excludeDefaults>true</excludeDefaults>
<outputDirectory>${project.build.directory}/site</outputDirectory>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
</plugin>
</plugins>
</reporting>
To generate the report, type mvn site. The reports will be created under target/site.

To combine with #alexbt answer you can utilize the report you have with Jacoco but plug that report into SonarQube (you can easily install it locally) then get the SonarLint Eclipse plugin that connects to the local SonarQube instance to get the integration you want.
In addition you get copy and paste detection and some redundant code checks. I say some because public methods are never marked as redundant.
Here are an examples of an online report with and without major problems
https://sonarcloud.io/dashboard?id=org.apache.maven:maven
https://sonarqube.com/dashboard?id=net.trajano.mojo:batik-maven-plugin
https://sonarcloud.io/component_measures/domain/Coverage?id=net.trajano.jetng:jetng
One bonus is you can centralize the rules for your team.

Execute TestNG.xml from Jenkins (Maven Project)

My Project dosnt have a bin folder
Have tried the following:
D:>java -cp "Pathtolibfolder\lib*;Pathtobinfolder\bin"
org.testng.TestNG testng.xml
Any Ideas?

If you are using Maven then i would simply use the surefire plugin and run tests as part of the build:
<plugins>
...
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>RELEASE</version>
<configuration>
<suiteXmlFiles>
<suiteXmlFile>testng.xml</suiteXmlFile>
</suiteXmlFiles>
</configuration>
</plugin>
...
</plugins>
Just specify the path to your testng.xml and take advantage of it if you can use this kind of configuration.
It allows for tons of parametrization and i have used it extensively in my projects.
Check out this tutorial to get a hang of it: http://maven.apache.org/surefire/maven-surefire-plugin/examples/testng.html

How to run whole test cases sequentially in maven using testng?

I want to run my whole test cases sequentially in java maven using testng.
How to run test suite sequentially?

Use Maven Surefire Plugin with TestNG (Using Suite XML Files)
<plugins>
[...]
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.18.1</version>
<configuration>
<suiteXmlFiles>
<suiteXmlFile>testng.xml</suiteXmlFile>
</suiteXmlFiles>
</configuration>
</plugin>
[...]
</plugins>
And to know how to configure the testng.xml please follow TestNG documentation.
Hope these information will guide you properly.

What is the best way to avoid maven-jar?

I am using a different plugin (ant4eclipse) to jar my files. What is the best way to avoid the maven-jar plugin from executing?
I tried to remove the <plugin>maven-jar-plugin</plugin>
I tried to <exclude> ** / * < / exclude>
I tried to <skip>true</skip>
None worked

In Maven 3.0.x (I tried 3.0.2) you can disable maven-jar-plugin by binding the default-jar execution to a nonexistent phase, as #bmargulies suggested. Unfortunately that doesn't work in 2.2.1, but you can prevent it from interfering with your own jar by setting an alternative <finalName> and <classifier> for the default-jar execution; it will still create a jar, but it will be set as a secondary artifact for the project and won't overwrite the one you've created. Here's an example that should work in both Maven 2 and Maven 3:
<project>
<modelVersion>4.0.0</modelVersion>
<groupId>test</groupId>
<artifactId>test</artifactId>
<version>0.1-SNAPSHOT</version>
<build>
<plugins>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<executions>
<execution>
<id>default-jar</id>
<phase>none</phase>
<configuration>
<finalName>unwanted</finalName>
<classifier>unwanted</classifier>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
Once you've disabled maven-jar-plugin, maven-install-plugin may give you trouble too. In Maven 3 it can be disabled the same as maven-jar-plugin: bind default-install to a nonexistent phase. However, in Maven 2 maven-install-plugin requires that the target/classes directory exist, and it will install the dummy jar when there isn't a primary artifact present.

This should do the trick - notice the use of <id>default-jar</id> and <phase/>.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.4</version>
<executions>
<execution>
<id>default-jar</id>
<phase/>
</execution>
</executions>
</plugin>
</plugins>
</build>

In my case, I only wanted to disable the jar plugin because the jar was empty. You can use the skipIfEmpty option in the plugin configuration
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
<configuration>
<skipIfEmpty>true</skipIfEmpty>
</configuration>
</plugin>

What happens if you declare this?
<packaging>pom</packaging>
Even if it does what you're looking for, be careful. I'm not sure if there could be negative side effects -- such as other maven projects that depend on your jar not being able to locate it.

Using maven 3.3.9, the following worked for me:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.1.2</version>
<executions>
<execution>
<id>default-jar</id>
<phase>none</phase>
<configuration>
<finalName>unwanted</finalName>
<classifier>unwanted</classifier>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-install-plugin</artifactId>
<version>3.0.0-M1</version>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
So in case of the maven-jar-plugin, I bound it to a non-existent phase. For the maven-install-plugin, I used the "skip" configuration parameter. The documentation about it says: "Set this to true to bypass artifact installation. Use this for artifacts that does not need to be installed in the local repository."

Explicitly bind the jar plugin to a phase that doesn't exist.

As other's have said, it's not possible to turn it off, other than using <packaging>pom</packaging>, which turns everything off and is probably not what you want.
Even though it will generate twice, a working solution is to bind your jar process to the package phase, as that is guaranteed to run after the default. By overwriting the same JAR file, you'll find that yours is used wherever the original would have been.

I am using a different plugin to jar my files. What is the best way to avoid the maven-jar plugin from executing?
First, the jar:jar goal is bound by default on the package phase for a project with a packaging of type jar. Second, there is no way to unbind a plugin bound to a phase. So, if you are using another plugin(?), either accept to produce 2 JARs or change the packaging (but I don't think this will work well).

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>