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mavenclasspathexecutable-jarmaven-assembly-pluginuima

How to "append" to a resource included with a Maven dependency during assembly


I'm trying to create a Maven artifact which should create an executable package (in JAR format), and this artifact depends on another project which itself depends on the artifact org.apache.uima.uimafit-core 2.1.0:

<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.stackoverflow.examples</groupId>
    <artifactId>amend-included-resource</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>${project.artifactId}</name>

    <properties>
        <java.version>1.8</java.version>
        <mainClass>com.stackoverflow.examples.AnalysisEngineTest</mainClass>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <build>
        <plugins>
            <plugin>
                <!-- Adapted from <http://stackoverflow.com/a/574650/1391325> -->
                <artifactId>maven-assembly-plugin</artifactId>
                <version>2.6</version>
                <configuration>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <mainClass>${mainClass}</mainClass>
                        </manifest>
                    </archive>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id> <!-- this is used for inheritance merges -->
                        <phase>package</phase> <!-- bind to the packaging phase -->
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>com.stackoverflow.examples</groupId>
            <artifactId>uimafit-stuff</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
    </dependencies>
</project>

The dependency uimafit-stuff defines a uimaFIT types.txt type description file under main/resources/META-INF/types.txt:

classpath*:desc/type/metadata.xml

Therefore, the project structure look something like this:

uimafit-stuff
├── desc
│   ├── type
│   │   ├── metadata.xml
├── META-INF
│   ├── org.apache.uima.fit
│   │   ├── types.txt < "classpath*:desc/type/metadata.xml"

Additionally, I have my own types.txt file under amend-included-resource/src/main/resources/META-INF/types.txt:

classpath*:desc/types/MyOwnSpecialType.xml

In order for my package to work, I need the union of the sets of type descriptors represented by each of these files (i.e. I need to append my type descriptor paths to the included file or vice versa). When I run mvn package, the artifact file without dependencies contains only "my" types.txt:

amend-included-resource-0.0.1-SNAPSHOT.jar
├── desc
│   ├── types
│   │   ├── MyOwnSpecialType.xml
├── META-INF
│   ├── org.apache.uima.fit
│   │   ├── types.txt < "classpath*:desc/types/MyOwnSpecialType.xml"

However, the JAR created during assembly using the descriptor jar-with-dependencies contains the types.txt file from uimafit-stuff and not the one from my own project:

amend-included-resource-0.0.1-SNAPSHOT-jar-with-dependencies.jar
├── desc
│   ├── type
│   │   ├── metadata.xml
│   ├── types
│   │   ├── MyOwnSpecialType.xml
├── META-INF
│   ├── org.apache.uima.fit
│   │   ├── types.txt < "classpath*:desc/type/metadata.xml"

How can I then ensure that both versions of the resource types.txt are somehow "unified" so that I can run my assembled jar without runtime errors?


Solution

  • This is explained in the uimaFIT documentation on building executable JARs.

    Here the relevant section (under Apache License 2.0)

    <build>
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-shade-plugin</artifactId>
          <version>2.2</version>
          <executions>
            <execution>
              <phase>package</phase>
              <goals><goal>shade</goal></goals>
              <configuration>
                <transformers>
                  <!-- Set the main class of the executable JAR -->
                  <transformer
                    implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                    <mainClass>org.apache.uima.fit.example.Main</mainClass>
                  </transformer>
                  <!-- Merge the uimaFIT configuration files -->
                  <transformer
                    implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                    <resource>META-INF/org.apache.uima.fit/fsindexes.txt</resource>
                  </transformer>
                  <transformer
                    implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                    <resource>META-INF/org.apache.uima.fit/types.txt</resource>
                  </transformer>
                  <transformer
                    implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                    <resource>META-INF/org.apache.uima.fit/typepriorities.txt</resource>
                  </transformer>
                  <!-- 
                    Prevent huge shaded artifacts from being deployed
                    to a Maven repository (remove if not desired) 
                  -->
                  <outputFile>${project.build.directory}/${artifactId}-${version}-standalone.jar</outputFile>
                </transformers>
              </configuration>
            </execution>
          </executions>
        </plugin>
      </plugins>
    </build>