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Use JAXB with plexus-compiler-eclipse plugin in maven profile

I am working on a project where we want to use the plexus-compiler-eclipse plugin during a Jenkins pipeline to check for increases in the number of warnings generated by the Eclipse compiler. We still want to use the javac compiler for the normal build and test stage, so I am trying to create a maven profile we can run during the warnings stage that utilizes the Eclipse compiler.
When I run the Eclipse compiler over our code, I get a compile error about JAXB dependencies being missing. I know this is due to our move to Java 11 from Java 1.8, but we do not get this error when building with the javac compiler. I have tried adding the jakarta.xml.bind-api dependency to the maven-compiler-plugin, but this does not help, nor does adding the org.glassfish.jaxb dependency or the javax.xml.bind:jaxb-api dependency.
I cannot share the full pom because this project is proprietary, but the profile I'm building looks like this:
<profile>
<id>eclipse-compile</id>
<activation>
<activeByDefault>false</activeByDefault>
</activation>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1></version>
<configuration>
<compilerId>eclipse</compilerId>
<source>${java.version}</source>
<target>${java.version}</target>
<compilerArguments>
<properties>${project.basedir}/.settings/org.eclipse.jdt.core.prefs</properties>
</compilerArguments>
</configuration>
<dependencies>
<dependency>
<groupId>org.codehaus.plexus</groupId>
<artifactId>plexus-compiler-eclipse</artifactId>
<version>2.8.8</version>
</dependency>
<dependency>
<groupId>org.eclipse.jdt</groupId>
<artifactId>ecj</artifactId>
<version>3.25.0</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</pluginManagement>
</build>
</profile>
I was putting the various JAXB dependencies I tried in the <dependencies> section under the org.eclipse.jdt entry.
Anyone else encounter this or know what to do about it?

The issue stemmed from the Maven build running in Java 11 but our normal compile stage forking to a Java 1.8 executable. Because the Plexus compiler cannot fork to a new environment, there was not a way for it to access the Java EE dependencies. We just need to update our entire project to be compatible with Java 11 at compile-time.

Why JRE Library is changed after Maven Update in Eclipse?

I'm an Intellij user and now I need to use Eclipse to create a Maven web app. So I installed Eclipse, I added Tomcat and all. And I want to use Java 8 for my projects, but I have a problem because I try to change JRE System Library from 1.7 to 1.8, and when I do Maven -> Update Project it becomes 1.7. And I don't understand why.
So I create a Maven project and I choose the webapp archetype from org.apache.maven and at the beginning my project has JRE System Library 1.7
After that I try to choose it like this:
After that the JRE System Library becomes 1.8:
After that I do right click Maven -> Update project and the JRE System Library becomes 1.7:
Why the JRE Library is changed from 1.8 to 1.7 after Maven update? And what should I do to have JRE System Library 1.8?
This is my pom:
<?xml version="1.0" encoding="UTF-8"?>
<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>com.abc</groupId>
<artifactId>firstwebproj</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<name>firstwebproj Maven Webapp</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<finalName>firstwebproj</finalName>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.2.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
Thanks in advance!

Look at your first picture. In the greyed out "Execution Environment" choice, the textfield has the content "JavaSE-1.7 (jdk1.8.0_201)". That JDK version is the same one you're trying to set it to use, but you have that JDK distro associated with Java SE 1.7.
In Eclipse Preferences, go to "Installed JREs", but go to the subfolder of that, "Execution Environments". In the left-hand list, you will see entries for "JavaSE-1.7" and hopefully "JavaSE-1.8". When you click each one of those, the right-hand list will populate with any available JDK/JRE installations.
You need to make sure that when you select "JavaSE-1.7", that NONE of the JDK 1.8 instlalations are checked in the right-hand list, and when you select "JavaSE-1.8, you have the desired JDK 1.8 distribution checked in the right-hand list.

What is "<release>" element on "<configuration>" for the "maven-compiler-plugin" in a JavaFX app

I used the org.openjfx:javafx-archetype-simple Maven archetype to start my first JavaFX project.
The resulting 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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example.invoicing</groupId>
<artifactId>Invoicer</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>14</maven.compiler.source>
<maven.compiler.target>14</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx-controls</artifactId>
<version>14</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<release>14</release> 🡄 ???
</configuration>
</plugin>
<plugin>
<groupId>org.openjfx</groupId>
<artifactId>javafx-maven-plugin</artifactId>
<version>0.0.4</version>
<configuration>
<mainClass>com.example.invoicing.App</mainClass>
</configuration>
</plugin>
</plugins>
</build>
</project>
➥ What is the purpose of the <release>14</release> line in <configuration> for the plugin <artifactId>maven-compiler-plugin</artifactId>?
I found this documentation for the Maven Compiler Plugin, Compiling Your Java Sources. But it only mentions <!-- put your configurations here -->. So I do not know anything about specific configuration options here.
Is <release>14</release> the version of Java being used to compile? Is it the version of OpenJFX? Something else?
I tried using 28 arbitrarily. Doing a Maven > install threw this error with an unhelpful error message with no clue as to a release of what product:
Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project Invoicer: Fatal error compiling

The release flag is equivalent to specifying the source and target of the same value for the compiler plugin. It supports the -release argument for the Java compiler since Java-9.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>14</source>
<target>14</target>
</configuration>
</plugin>
Note: For the same reason, you can get rid of the redundant properties declared as
<maven.compiler.source>14</maven.compiler.source>
<maven.compiler.target>14</maven.compiler.target>
Further: What is the --release flag in the Java 9 compiler? | The -release flag in javac was introduced to Compile for Older Platform Versions.
To complete the answer over the part where you've tried the version value as 28. While using Maven version -
Apache Maven 3.6.1 (d66c9c0b3152b2e69ee9bac180bb8fcc8e6af555; 2019-04-05T00:30:29+05:30)
The error message reads very clearly what it should (if you could share the complete logs in the question)
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project forty-bits-of-java:
Fatal error compiling: error: release version 28 not supported

The compile options page states that this ends up as the -release argument passed to javac.
And about --release release:
Compiles against the public, supported and documented API for a specific VM version. Supported release targets are 6, 7, 8, and 9.
As I understand it, Java 9 introduced a feature that helps developers build on a recent compiler, targeting an older runtime, but at the same time preventing the old problem that let code compile with references to newer APIs while being targeted at old runtimes.
See: JEP 247: Compile for Older Platform Versions
Ex: If you use Java 8 to compile code that uses new Java 8 APIs (such as Collection.stream()), with a target of 1.7, this code compiles but will fail at runtime on Java 7 with a NoSuchMethodError.
On JDK 9, if you use --release 1.7, the compiler will know that Collection.stream() can't be correctly targeted at Java 7 and will fail the build.

tl;dr
In your POM, replace the two tags source & target as seen here:
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<!--The following `source` and `target` tags are now replaced by `release` seen further down below.-->
<!--<maven.compiler.source>14</maven.compiler.source>-->
<!--<maven.compiler.target>14</maven.compiler.target>-->
</properties>
…with the new release tag, placed further down in POM:
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
…
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<!--Enable Java language preview features. Specify Java version.-->
<!--This `release` tag replaced the pair of `source` and `target` tags seen commented-out near top of this POM.-->
<release>14</release>
</configuration>
</plugin>
…
…to tell the Java compiler the version of Java on which you intend to deploy. This tag passes a release flag to the Java compiler. The compiler errors out any of your code trying to use an API added to later versions of Java.
See another Question: What is the --release flag in the Java 9 compiler?
Details
Both Answers by Naman and by ernest_k are correct and important. But I need to write this Answer to combine them and show the direct solution.
Problem
The issue is that JEP 247: Compile for Older Platform Versions added a feature in Java 9 for a new compiler flag -release to replace the combination of older -source, -target, and -bootclasspath flags. This plugs a hole that plagued programmers trying to work on the latest compiler while writing code limited to making API calls of an earlier version of Java.
For example, I may be writing on my Mac using Java 12 yet deploying to a server running Java 8. I want the compiler to stop me from accidentally using features that arrived in later versions of Java. Otherwise, my app will succeed at compile-time yet fail at run-time when those features are unavailable on the older JVM.
To quote the JEP:
Summary
Enhance javac so that it can compile Java programs to run on selected older versions of the platform.
Motivation
javac provides two command line options, -source and -target, which can be used to select the version of the Java language accepted by the compiler and the version of the class files it produces, respectively. By default, however, javac compiles against the most-recent version of the platform APIs. The compiled program can therefore accidentally use APIs only available in the current version of the platform. Such programs cannot run on older versions of the platform, regardless of the values passed to the -source and -target options. This is a long-term usability pain point, since users expect that by using these options they'll get class files that can run on the the platform version specified by -target.
Solution
In a Maven-driven project, we pass those flags to the Java compiler by setting tags on our Maven POM file.
In your Maven POM file’s tag hierarchy of:
<project> …
<build> …
<pluginManagement> …
<plugins> …
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
…nest the following tag hierarchy, within which we specify our desired deployment version of Java.
<configuration>
<release>14</release>
By the way, if using a version of Java offering "preview" features, we can nest a further tag and value if we wish to enable those preview features.
<compilerArgs>--enable-preview</compilerArgs>
The old-school settings replaced by the new release tag were a pair of tags, source and target. These two could be set in Maven to be passed along to the Java compiler. So if you add the release tag seen above, check to see if your POM has this pair of tags. If found, delete them.
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>14</maven.compiler.source> 🡄 Delete if using `release` tag.
<maven.compiler.target>14</maven.compiler.target> 🡄 Delete if using `release` tag.
</properties>
Example POM file
Here is a complete example POM file for Maven 3.6.3, for a basic Java project.
We are using all the latest versions of various plugins and dependencies. This example uses Java 15 with preview features such as Records enabled.
<?xml version="1.0" encoding="UTF-8"?>
<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>work.basil.demo</groupId>
<artifactId>Demo5</artifactId>
<version>1.0-SNAPSHOT</version>
<name>Demo5</name>
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<!--The following `source` and `target` tags are now replaced by `release` seen further down below.-->
<!--<maven.compiler.source>15</maven.compiler.source>-->
<!--<maven.compiler.target>15</maven.compiler.target>-->
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>5.7.0-M1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<!--Enable Java language preview features. Specify Java version.-->
<!--This `release` tag replaced the pair of `source` and `target` tags seen commented-out near top of this POM.-->
<release>15</release>
<compilerArgs>
--enable-preview
</compilerArgs>
</configuration>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>3.0.0-M4</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>3.2.0</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>3.0.0-M1</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>3.0.0-M1</version>
</plugin>
<!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.8.2</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.1.0</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
JavaFX
You mentioned JavaFX in your Question. Note that this discussion applies to any and all Maven-driven Java projects. This includes JavaFX projects as well as Jakarta Servlets, console apps, and so on. Nothing here is specific to JavaFX.

Eclipse Maven and Java 8 problems

I moved from simple web app to maven web app and with Eclipse Neon I encountered a frustrating problem: after I add in pom.xml the specification to use Java 8 or 7, it doesn't work.
To verify if it works I write a simple class where I use a try(expression) declaration.
What should I have to do to use Java 8 in maven (I have installed and it works in normal web app)?
The code of pom.xml is this:
<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>com.webdata</groupId>
<artifactId>WebParser</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>WebParser</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>net.sourceforge.htmlunit</groupId>
<artifactId>htmlunit</artifactId>
<version>2.23</version>
</dependency>
</dependencies>
</project>

First, your JAVA_HOME must point to a JDK 1.8.
Else if is not the case, you must specify a JDK 1.8 as source and target in the compiler configuration of your pom.xml in this way :
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
<compilerVersion>1.8</compilerVersion>
<fork>true</fork>
<executable>D:\jdk1.8\bin\javac</executable>
</configuration>
</plugin>
Then, in eclipse, you must check in Preferences that :
Java->Installed JREs has a 1.8 JRE/JDK installed.
You could set the following as default if you want to use the 1.8 for any new created projects in your Eclipse :
Java->Installed JREs : select the 1.8.
Java->Compiler : select the JDK compiler compliance level to 1.8.
If the default preferences don't use 1.8 compilation compliance and JDK/JRE or that the project was created outside from this Eclipse with preferences set to 1.8 compilation compliance and JDK/JRE, you should check and maybe adjust properties of your Eclipse project
To do it, go in the properties of your project, then Java Build Path and in the Libraries tab. You must check that the JRE System Library uses Java 1.8. If it is not the case, remplace it with the 1.8 version.
When it is done, always in the properties of your project, go to Java Compiler and check that you use JDK compiler compliance with Java 1.8.
It should work.

It's funny :))
I searched 3-4 hours and I tried few methods and only after I asked here I found the solution :)
Right click on the project -> Properties -> Java Compiler -> uncheck 'Use compilance from execution...' and choose '1.8'

In pom.xml, defined this maven.compiler.source properties to tell Maven to use Java 8 to compile the project.
Maven Properties Java 8
<properties>
<maven.compiler.target>1.8</maven.compiler.target>
<maven.compiler.source>1.8</maven.compiler.source>
</properties>
Compiler Plugin - Alternative, configure the plugin directly.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>

This worked for me:
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
as mentioned here -> maven-compiler-plugin
Don't forget to update Maven project -> Alt + F5.

Problems converting Dynamic Web Project to Maven

I'm using Eclipse Luna with Websphere Application Sever 8.5.
When I run a dynamic web project using the Websphere Application Sever 8.5 it runs fine.
However, when I convert a dynamic web project to a maven project, i'm getting around 53 errors starting with Missing artifact com.ibm.websphere e.g Missing artifact com.ibm.websphere.xml:xmlapi:jar:1.0.0' all located in my pom.xml.
I am also getting this error:
The container 'Maven Dependencies' references non existing library
C:\Users\Brian242\.m2\repository\com\ibm\websphere\ws\com.ibm.ws.wccm\1.0.0\com.ibm.ws.wccm-1.0.0.jar'
Not sure if that's part of the problem.
I've looked everywhere for a solution but haven't found anything. So I have decided to ask for some help. Does anyone know how to solve the above problem/s?
Thank you,
Brian
<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>TrialProj</groupId>
<artifactId>TrialProj</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<dependencies>
<dependency>
<groupId>com.ibm.tools.target</groupId>
<artifactId>was</artifactId>
<version>8.5.5</version>
<type>pom</type>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.4</version>
<configuration>
<warSourceDirectory>WebContent</warSourceDirectory>
<failOnMissingWebXml>false</failOnMissingWebXml>
</configuration>
</plugin>
</plugins>
</build>
</project>

you created M2_REPO environment variable?
right click on the project root
Build Path-> Configure Puild Path ...
Click button 'Add Variable'
Click 'Set Variable ...'
Click 'New ...'
name: M2_REPO
Path: / path_to_repository_the_maven /
Click Ok
Recompile

If you are using eclipse make sure you add suport for eclipse web tools using:
mvn eclipse:eclipse -Dwtpversion=2.0
(2.0 or your required version) And afterwards recompile maven project:
mvn compile