Add profile for creating an unshaded uberjar

This commit is dedicated to Adrian Wolny.

Author: ctrueden

pom.xml

@@ -4,7 +4,7 @@
 
 	<groupId>org.scijava</groupId>
 	<artifactId>pom-scijava-base</artifactId>
-	<version>9.0.1-SNAPSHOT</version>
+	<version>9.1.0-SNAPSHOT</version>
 	<packaging>pom</packaging>
 
 	<name>SciJava Base POM</name>
@@ -139,6 +139,11 @@
 		-->
 		<automatic-module-name>${package-name}</automatic-module-name>
 
+		<!--
+		Name of the uberjar generated by the uberjar profile.
+		-->
+		<uberjar-classifier>all</uberjar-classifier>
+
 		<!--
 		The License which license-maven-plugin will use to populate.
 		See: license:update-file-header, license:update-project-license
@@ -227,6 +232,7 @@
 		<maven-plugin-plugin.version>3.6.0</maven-plugin-plugin.version>
 		<maven-release-plugin.version>2.5.3</maven-release-plugin.version>
 		<maven-resources-plugin.version>3.1.0</maven-resources-plugin.version>
+		<maven-shade-plugin.version>3.2.1</maven-shade-plugin.version>
 		<maven-site-plugin.version>3.7.1</maven-site-plugin.version>
 		<maven-source-plugin.version>3.1.0</maven-source-plugin.version>
 		<maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
@@ -458,6 +464,11 @@
 					<version>${maven-resources-plugin.version}</version>
 				</plugin>
 
+				<plugin>
+					<artifactId>maven-shade-plugin</artifactId>
+					<version>${maven-shade-plugin.version}</version>
+				</plugin>
+
 				<plugin>
 					<artifactId>maven-site-plugin</artifactId>
 					<version>${maven-site-plugin.version}</version>
@@ -1436,6 +1447,64 @@
 			</build>
 		</profile>
 
+		<!--
+		The uberjar profile augments the package phase to build an unshaded uber-JAR
+		or "fat JAR" using the maven-shade-plugin. The default classifier is "all";
+		override the ${uberjar-classifier} property to change it.
+
+		Uber-JARs are convenient for all-in-one distribution of a Java program,
+		freeing users from the burden of juggling multiple files and dependencies.
+		However, unshaded uberjars are not appropriate for use as dependencies
+		themselves, because the uber-JAR's embedded version of each dependency may
+		clash with other classpath components relying on those same dependencies.
+		It is advised to publish the standard (non-uber) JAR of your component with
+		proper dependency declarations as the main artifact, and deploy the uber-JAR
+		as a separate classifier.
+		-->
+		<profile>
+			<id>uberjar</id>
+			<build>
+				<plugins>
+					<plugin>
+						<groupId>org.apache.maven.plugins</groupId>
+						<artifactId>maven-shade-plugin</artifactId>
+						<executions>
+							<execution>
+								<phase>package</phase>
+								<goals>
+									<goal>shade</goal>
+								</goals>
+								<configuration>
+									<shadedClassifierName>${uberjar-classifier}</shadedClassifierName>
+									<createDependencyReducedPom>false</createDependencyReducedPom>
+									<shadedArtifactAttached>true</shadedArtifactAttached>
+									<transformers>
+										<transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
+											<resource>META-INF/json/org.scijava.plugin.Plugin</resource>
+										</transformer>
+									</transformers>
+									<filters>
+										<filter>
+											<!--
+											Shading signed JARs will fail without this.
+											http://stackoverflow.com/questions/999489/invalid-signature-file-when-attempting-to-run-a-jar
+											-->
+											<artifact>*:*</artifact>
+											<excludes>
+												<exclude>META-INF/*.SF</exclude>
+												<exclude>META-INF/*.DSA</exclude>
+												<exclude>META-INF/*.RSA</exclude>
+											</excludes>
+										</filter>
+									</filters>
+								</configuration>
+							</execution>
+						</executions>
+					</plugin>	
+				</plugins>
+			</build>
+		</profile>
+
 		<!--
 		The jdb profile launches the defined ${main-class} in the jdb debugger.
 		Launch it using: mvn -Pjdb exec:exec