Get Maven Artifact Version at Runtime

Get Maven artifact version at runtime

You should not need to access Maven-specific files to get the version information of any given library/class.

You can simply use getClass().getPackage().getImplementationVersion() to get the version information that is stored in a .jar-files MANIFEST.MF. Luckily Maven is smart enough Unfortunately Maven does not write the correct information to the manifest as well by default!

Instead one has to modify the <archive> configuration element of the maven-jar-plugin to set addDefaultImplementationEntries and addDefaultSpecificationEntries to true, like this:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-jar-plugin</artifactId>
    <configuration>
        <archive>                   
            <manifest>
                <addDefaultImplementationEntries>true</addDefaultImplementationEntries>
                <addDefaultSpecificationEntries>true</addDefaultSpecificationEntries>
            </manifest>
        </archive>
    </configuration>
</plugin>

Ideally this configuration should be put into the company pom or another base-pom.

Detailed documentation of the <archive> element can be found in the Maven Archive documentation.

Getting maven project version and artifact ID from pom while running in Eclipse

Create a property file

src/main/resources/project.properties

with the below content

version=${project.version}
artifactId=${project.artifactId}

Now turn on maven resource filtering

  <resource>
    <directory>src/main/resources</directory>
    <filtering>true</filtering>
  </resource>

so that this file is processed into

target/classes/project.properties

with some content similar to this

version=1.5
artifactId=my-artifact

Now you can read this property file to get what you want and this should work every time.

final Properties properties = new Properties();
properties.load(this.getClassLoader().getResourceAsStream("project.properties"));
System.out.println(properties.getProperty("version"));
System.out.println(properties.getProperty("artifactId"));

Retrieve version from maven pom.xml in code

Assuming you're using Java, you can:

1. Create a .properties file in (most commonly) your src/main/resources directory (but in step 4 you could tell it to look elsewhere).

2. Set the value of some property in your .properties file using the standard Maven property for project version:

   foo.bar=${project.version}
   

3. In your Java code, load the value from the properties file as a resource from the classpath (google for copious examples of how to do this, but here's an example for starters).

4. In Maven, enable resource filtering. This will cause Maven to copy that file into your output classes and translate the resource during that copy, interpreting the property. You can find some info here but you mostly just do this in your pom:

   <build>
     <resources>
       <resource>
         <directory>src/main/resources</directory>
         <filtering>true</filtering>
       </resource>
     </resources>   
   </build>
   

You can also get to other standard properties like project.name, project.description, or even arbitrary properties you put in your pom <properties>, etc. Resource filtering, combined with Maven profiles, can give you variable build behavior at build time. When you specify a profile at runtime with -PmyProfile, that can enable properties that then can show up in your build.

Get Maven artifact version at runtime from package without java classes

Using the method found in second answer here:
reading MANIFEST.MF file from jar file using JAVA
and adding a conditional in the Attributes - checking on the title as presented in MANIFEST.MF returns the proper version.

public static String getManifestInfo() {
        Enumeration resEnum;
        try {
            resEnum = Thread.currentThread().getContextClassLoader().getResources(JarFile.MANIFEST_NAME);
            while (resEnum.hasMoreElements()) {
                try {
                    URL url = (URL)resEnum.nextElement();
                    InputStream is = url.openStream();
                    if (is != null ) {
                        Manifest manifest = new Manifest(is);
                        Attributes mainAttribs = manifest.getMainAttributes();
                        String version = mainAttribs.getValue("Implementation-Version");
                        String name = mainAttribs.getValue("Implementation-Title");
                        if (version != null && name != null) {
                            if ("packagetitle".equals(name))
                                return version;
                        }
                    }
                }
                catch (Exception e) {
                    // Silently ignore wrong manifests on classpath?
                }
            }
        } catch (IOException e1) {
            // Silently ignore wrong manifests on classpath?
        }
        return null;
    }

This can surely be made even more effectively by skipping the iteration using stream() if knowing details about the package itself, but at least this works as intended.

How to log the pom artifact and version

Solution A: Maven resource filtering

Your POM snippet should replace the variables correctly, if you put it in the right POM section:

<build>
  <resources>
    <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
    </resource>
  </resources>
</build>

You can inspect the result in the target/classes folder. After I fixed your faulty pseudo code by adding an empty argument list () to your method name and replaced the nonsensical this.getClassLoader() by getClass().getClassLoader(), the code even compiles and does something meaningful. Do you ever test before you post something to a public platform like StackOverflow?

import java.io.IOException;
import java.util.Properties;

public class ClassA {
  public void methodA() throws IOException {
    final Properties properties = new Properties();
    properties.load(getClass().getClassLoader().getResourceAsStream("project.properties"));
    System.out.println(properties.getProperty("version"));
    System.out.println(properties.getProperty("artifactId"));
  }

  public static void main(String[] args) throws IOException {
    new ClassA().methodA();
  }
}

Console log when running from IntelliJ IDEA after mvn compile (because we need Maven to process the resources and copy them to target/classes):

1.9.8-SNAPSHOT
util

Or whatever your module name and version are.

If you see the variable names instead, either your classpath does not point to the JAR but to the source directory somehow, or you have multiple modules with a project.properties file and in one of them forgot resource filtering. Whichever file is found first on the class path, will be loaded. So in a multi-module project, you better use different file names, otherwise it is more or less a lottery which one if found first.

The next problem would then be for your aspect or other module to know which resource file to load, so that better be linked to class or package names somehow in order for the other module to be able to guess the resource file from the package name. You do need clean package name separation between modules then. I really wonder if it is worth the trouble.

Solution B: Templating Maven Plugin + package-info.java + custom annotation

Another idea would be to use resource filtering or a plugin like org.codehaus.mojo:templating-maven-plugin for replacing the versions directly into package annotation values in a package-info.java file and then simply fetch the values during runtime from the package info. I made a quick & dirty local test with that plugin, and it works nicely. I recommend to keep it simple for now and just fix your resource filtering problem. If you need the more generic solution I just described, please let me know.

Project structure

Update: I extracted the quick solution I hacked into one of my projects into a new Maven multi-module project in order to show you a clean solution as follows:

Say, we have a parent POM with 3 sub-modules:

• annotation - contains an annotation to be used on packages in package-info.java files. Can easily be modified to also be applicable to classes.
• library - example library to be accessed by an application module
• application - example application

You can find the full project on GitHub:
https://github.com/kriegaex/SO_Maven_ArtifactInfoRuntime_68321439

The project's directory layout is as follows:

$ tree
.
├── annotation
│   ├── pom.xml
│   └── src
│       └── main
│           └── java
│               └── de
│                   └── scrum_master
│                       └── stackoverflow
│                           └── q68321439
│                               └── annotation
│                                   └── MavenModuleInfo.java
├── application
│   ├── pom.xml
│   └── src
│       ├── main
│       │   ├── java
│       │   │   └── de
│       │   │       └── scrum_master
│       │   │           └── stackoverflow
│       │   │               └── q68321439
│       │   │                   └── application
│       │   │                       └── Application.java
│       │   └── java-templates
│       │       └── de
│       │           └── scrum_master
│       │               └── stackoverflow
│       │                   └── q68321439
│       │                       └── application
│       │                           └── package-info.java
│       └── test
│           └── java
│               └── de
│                   └── scrum_master
│                       └── stackoverflow
│                           └── q68321439
│                               └── application
│                                   └── ModuleInfoTest.java
├── library
│   ├── pom.xml
│   └── src
│       └── main
│           ├── java
│           │   └── de
│           │       └── scrum_master
│           │           └── stackoverflow
│           │               └── q68321439
│           │                   └── library
│           │                       └── LibraryClass.java
│           └── java-templates
│               └── de
│                   └── scrum_master
│                       └── stackoverflow
│                           └── q68321439
│                               └── library
│                                   └── package-info.java
└── pom.xml

Please note the src/java-templates directories in both the library and the application modules, containing package-info.java files. The directory name is the default for Templating Maven Plugin, making plugin configuration less verbose.

Parent 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>de.scrum-master.stackoverflow.q68321439</groupId>
  <artifactId>maven-artifact-info-runtime</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>pom</packaging>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <maven.compiler.source>8</maven.compiler.source>
    <maven.compiler.target>8</maven.compiler.target>
  </properties>

  <modules>
    <module>annotation</module>
    <module>library</module>
    <module>application</module>
  </modules>

  <build>
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>org.codehaus.mojo</groupId>
          <artifactId>templating-maven-plugin</artifactId>
          <version>1.0.0</version>
          <executions>
            <execution>
              <id>filter-src</id>
              <goals>
                <goal>filter-sources</goal>
              </goals>
            </execution>
          </executions>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>

</project>

Module annotation

<?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>

  <parent>
    <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
    <artifactId>maven-artifact-info-runtime</artifactId>
    <version>1.0-SNAPSHOT</version>
  </parent>

  <artifactId>annotation</artifactId>

</project>

package de.scrum_master.stackoverflow.q68321439.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PACKAGE)
public @interface MavenModuleInfo {
  String groupId();
  String artifactId();
  String version();
}

Module library

<?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>

  <parent>
    <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
    <artifactId>maven-artifact-info-runtime</artifactId>
    <version>1.0-SNAPSHOT</version>
  </parent>

  <artifactId>library</artifactId>

  <build>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>templating-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>

  <dependencies>
    <dependency>
      <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
      <artifactId>annotation</artifactId>
      <version>${project.version}</version>
    </dependency>
  </dependencies>

</project>

package de.scrum_master.stackoverflow.q68321439.library;

public class LibraryClass {}

Please note that the following file needs to be located in library/src/main/java-templates/de/scrum_master/stackoverflow/q68321439/library/package-info.java. Here you can see how we use Maven properties to be replaced by their corresponding values during the build process by Templating Maven Plugin:

/**
 * This is the package description (...)
 */
@MavenModuleInfo(groupId = "${project.groupId}", artifactId = "${project.artifactId}", version = "${project.version}")
package de.scrum_master.stackoverflow.q68321439.library;

import de.scrum_master.stackoverflow.q68321439.annotation.MavenModuleInfo;

Module application

<?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>

  <parent>
    <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
    <artifactId>maven-artifact-info-runtime</artifactId>
    <version>1.0-SNAPSHOT</version>
  </parent>

  <artifactId>application</artifactId>

  <build>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>templating-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>

  <dependencies>
    <dependency>
      <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
      <artifactId>annotation</artifactId>
      <version>${project.version}</version>
    </dependency>
    <dependency>
      <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
      <artifactId>library</artifactId>
      <version>${project.version}</version>
    </dependency>
    <dependency>
      <groupId>de.scrum-master.stackoverflow.q68321439</groupId>
      <artifactId>library</artifactId>
      <version>${project.version}</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.13.2</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

</project>

package de.scrum_master.stackoverflow.q68321439.application;

public class Application {
  public static void main(String[] args) {}
}

Please note that the following file needs to be located in application/src/main/java-templates/de/scrum_master/stackoverflow/q68321439/application/package-info.java. Here you can see how we use Maven properties to be replaced by their corresponding values during the build process by Templating Maven Plugin:

/**
 * This is the package description (...)
 */
@MavenModuleInfo(groupId = "${project.groupId}", artifactId = "${project.artifactId}", version = "${project.version}")
package de.scrum_master.stackoverflow.q68321439.application;

import de.scrum_master.stackoverflow.q68321439.annotation.MavenModuleInfo;

package de.scrum_master.stackoverflow.q68321439.application;

import de.scrum_master.stackoverflow.q68321439.annotation.MavenModuleInfo;
import de.scrum_master.stackoverflow.q68321439.library.LibraryClass;
import org.junit.Test;

import static org.junit.Assert.assertEquals;

public class ModuleInfoTest {
  @Test
  public void test() {
    String groupId = "de.scrum-master.stackoverflow.q68321439";

    MavenModuleInfo libMavenInfo = logAndGetMavenModuleInfo("Library Maven info", LibraryClass.class.getPackage());
    assertEquals(groupId, libMavenInfo.groupId());
    assertEquals("library", libMavenInfo.artifactId());

    MavenModuleInfo appMavenInfo = logAndGetMavenModuleInfo("Application Maven info", Application.class.getPackage());
    assertEquals(groupId, appMavenInfo.groupId());
    assertEquals("application", appMavenInfo.artifactId());
  }

  private MavenModuleInfo logAndGetMavenModuleInfo(String message, Package aPackage) {
    MavenModuleInfo moduleInfo = aPackage.getAnnotation(MavenModuleInfo.class);
    System.out.println(message);
    System.out.println("  " + moduleInfo.groupId());
    System.out.println("  " + moduleInfo.artifactId());
    System.out.println("  " + moduleInfo.version());
    return moduleInfo;
  }
}

Run Maven build

Now run the Maven build via mvn clean test:

(...)
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ application ---
[INFO] Surefire report directory: C:\Users\alexa\Documents\java-src\SO_Maven_ArtifactInfoRuntime_68321439\application\target\surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running de.scrum_master.stackoverflow.q68321439.application.ModuleInfoTest
Library Maven info
  de.scrum-master.stackoverflow.q68321439
  library
  1.0-SNAPSHOT
Application Maven info
  de.scrum-master.stackoverflow.q68321439
  application
  1.0-SNAPSHOT
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.094 sec
(...)

Identifying the caller

Assuming that all calling modules implement the same scheme with package info + special annotation, you can print the caller info like this:

package de.scrum_master.stackoverflow.q68321439.library;

import de.scrum_master.stackoverflow.q68321439.annotation.MavenModuleInfo;

public class LibraryClass {
  public void doSomething() {
    StackTraceElement callerStackTraceElement = new Exception().getStackTrace()[1];
    try {
      Class<?> callerClass = Class.forName(callerStackTraceElement.getClassName());
      MavenModuleInfo mavenModuleInfo = callerClass.getPackage().getAnnotation(MavenModuleInfo.class);
      System.out.println(mavenModuleInfo.groupId());
      System.out.println(mavenModuleInfo.artifactId());
      System.out.println(mavenModuleInfo.version());
    }
    catch (ClassNotFoundException e) {
      e.printStackTrace();
    }
  }

  public void doSomethingJava9() {
    Class<?> callerClass = StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE).getCallerClass();
    MavenModuleInfo mavenModuleInfo = callerClass.getPackage().getAnnotation(MavenModuleInfo.class);
    System.out.println(mavenModuleInfo.groupId());
    System.out.println(mavenModuleInfo.artifactId());
    System.out.println(mavenModuleInfo.version());
  }

}

While doSomething() also works in old Java versions (tested on Java 8), on Java 9+ you can use the JEP 259 Stack-Walking API as shown in doSomethingJava9(). In that case, you do not need to manually parse an exception stack trace and handle exceptions.

Solution C: Identifying the calling JAR via URL classloader

Assuming that you use my sample project and call the library from the application module (like in the previous section), a quick & dirty way to print JAR information would be this:

Add this method to LibraryClass:

  public void doSomethingClassLoader() {
    StackTraceElement callerStackTraceElement = new Exception().getStackTrace()[1];
    try {
      Class<?> callerClass = Class.forName(callerStackTraceElement.getClassName());
      // Cheap way of getting Maven artifact name - TODO: parse
      System.out.println(
        callerClass
          .getClassLoader()
          .getResource(callerStackTraceElement.getClassName().replaceAll("[.]", "/") + ".class")
      );
    }
    catch (ClassNotFoundException e) {
      e.printStackTrace();
    }
  }

Again, on Java 9+ you could make the code nicer by using the Stack-Walking API, see above.

Call the method from Application:

public class Application {
  public static void main(String[] args) {
//    new LibraryClass().doSomething();
//    new LibraryClass().doSomethingJava9();
    new LibraryClass().doSomethingClassLoader();
  }
}

Now build the Maven application from the command line and run with 3 different classpaths, pointing to

1. the target/classes directory
2. the JAR in the target directory
3. the JAR in the local Maven repository
   in order to see what kind of information gets printed to the console:

$ mvn install
(...)

$ java -cp "annotation\target\annotation-1.0-SNAPSHOT.jar;library\target\library-1.0-SNAPSHOT.jar;application\target\classes" de.scrum_master.stackoverflow.q68321439.application.Application

file:/C:/Users/alexa/Documents/java-src/SO_Maven_ArtifactInfoRuntime_68321439/application/target/classes/de/scrum_master/stackoverflow/q68321439/application/Application.class

$ java -cp "annotation\target\annotation-1.0-SNAPSHOT.jar;library\target\library-1.0-SNAPSHOT.jar;application\target\application-1.0-SNAPSHOT.jar" de.scrum_master.stackoverflow.q68321439.application.Application

jar:file:/C:/Users/alexa/Documents/java-src/SO_Maven_ArtifactInfoRuntime_68321439/application/target/application-1.0-SNAPSHOT.jar!/de/scrum_master/stackoverflow/q68321439/application/Application.class

$ java -cp "annotation\target\annotation-1.0-SNAPSHOT.jar;library\target\library-1.0-SNAPSHOT.jar;c:\Users\Alexa\.m2\repository\de\scrum-master\stackoverflow\q68321439\application\1.0-SNAPSHOT\application-1.0-SNAPSHOT.jar" de.scrum_master.stackoverflow.q68321439.application.Application

jar:file:/C:/Users/alexa/.m2/repository/de/scrum-master/stackoverflow/q68321439/application/1.0-SNAPSHOT/application-1.0-SNAPSHOT.jar!/de/scrum_master/stackoverflow/q68321439/application/Application.class

As you can see

• in case 1, you can indirectly infer the Maven artifact from the project path,
• in case 2, you see artifact ID and version in the JAR name and the group ID indirectly in the project path,
• in case 3, you see artifact ID and version in the JAR name and the group ID directly in the Maven repository path.

Of course, you could parse that information and print it in a more structured way, but I suggest to simply print it like this and let the human brain reading the log do the parsing.

Like I said in a comment before, this works nicely in the case I showed you, also with different projects, not just in a single multi-module project. What kinds of information you would see in case of an application server deployment or uber JAR situation, strongly depends on the exact situation. There is no single, generic answer, and I cannot do your whole job for you. I showed you several options, now you can select one.

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