Full impl

.gitignore

@@ -18,6 +18,7 @@ cmake-build-*/
 out/
 build/
 work/
+target/
 .idea_modules/
 atlassian-ide-plugin.xml
 com_crashlytics_export_strings.xml

README.md

@@ -1,2 +1,4 @@
 # maven-git-versioning
-This plugin seamlessly converts standard "-SNAPSHOT" versions into a more descriptive format, "-dev-{gitDepth}-{gitHash}", allowing you to gain valuable insights into the exact commit from which each jar was built.
+
+This plugin seamlessly converts standard "-SNAPSHOT" versions into a more descriptive format, "
+-dev-{gitDepth}-{gitHash}", allowing you to gain valuable insights into the exact commit from which each jar was built.

pom.xml

@@ -1,34 +1,59 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
          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>
 
+    <name>Maven Git Versioning</name>
     <groupId>me.braydon</groupId>
-    <artifactId>maven-git-versioning</artifactId>
+    <artifactId>git-versioning-maven-plugin</artifactId>
-    <version>1.0-SNAPSHOT</version>
+    <version>1.0</version>
+    <packaging>maven-plugin</packaging>
 
     <properties>
-        <maven.compiler.source>8</maven.compiler.source>
+        <java.version>8</java.version>
-        <maven.compiler.target>8</maven.compiler.target>
+        <maven.compiler.source>${java.version}</maven.compiler.source>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven.compiler.target>${java.version}</maven.compiler.target>
+        <maven-plugin-tools.version>3.9.0</maven-plugin-tools.version>
     </properties>
 
     <build>
         <plugins>
+            <!--Used for compiling the source code with the proper Java version-->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.8.1</version>
+                <version>3.11.0</version>
                 <configuration>
-                    <source>8</source>
+                    <source>${java.version}</source>
-                    <target>8</target>
+                    <target>${java.version}</target>
+
+                    <!--Enable incremental builds, this is reversed due to-->
+                    <!--a bug as seen in https://issues.apache.org/jira/browse/MCOMPILER-209-->
+                    <useIncrementalCompilation>false</useIncrementalCompilation>
                 </configuration>
             </plugin>
+
+            <!--Handles shading of dependencies in the final output jar-->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-shade-plugin</artifactId>
-                <version>3.1.0</version>
+                <version>3.5.0</version>
+                <configuration>
+                    <createDependencyReducedPom>false</createDependencyReducedPom>
+                    <filters>
+                        <filter>
+                            <!-- Exclude META-INF directory from being shaded -->
+                            <artifact>*:*</artifact>
+                            <excludes>
+                                <exclude>META-INF/*.MF</exclude>
+                                <exclude>META-INF/*.SF</exclude>
+                                <exclude>META-INF/*.DSA</exclude>
+                                <exclude>META-INF/*.DSA</exclude>
+                            </excludes>
+                        </filter>
+                    </filters>
+                </configuration>
                 <executions>
                     <execution>
                         <phase>package</phase>
@@ -39,12 +64,60 @@
                 </executions>
             </plugin>
         </plugins>
-        <resources>
+
-            <resource>
+        <!-- Plugin Management -->
-                <directory>src/main/resources</directory>
+        <pluginManagement>
-                <filtering>true</filtering>
+            <plugins>
-            </resource>
+                <!-- Generate a help mojo -->
-        </resources>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-plugin-plugin</artifactId>
+                    <version>${maven-plugin-tools.version}</version>
+                    <executions>
+                        <execution>
+                            <id>help-mojo</id>
+                            <goals>
+                                <goal>helpmojo</goal>
+                            </goals>
+                        </execution>
+                    </executions>
+                </plugin>
+            </plugins>
+        </pluginManagement>
     </build>
 
+    <dependencies>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.28</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.jgit</groupId>
+            <artifactId>org.eclipse.jgit</artifactId>
+            <version>5.12.0.202106070339-r</version>
+            <scope>compile</scope>
+        </dependency>
+
+        <!-- Maven Plugin -->
+        <dependency>
+            <groupId>org.apache.maven</groupId>
+            <artifactId>maven-plugin-api</artifactId>
+            <version>3.9.3</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.maven.plugin-tools</groupId>
+            <artifactId>maven-plugin-tools-java</artifactId>
+            <version>${maven-plugin-tools.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.maven.plugin-tools</groupId>
+            <artifactId>maven-plugin-annotations</artifactId>
+            <version>${maven-plugin-tools.version}</version>
+            <scope>provided</scope>
+        </dependency>
+    </dependencies>
 </project>

src/main/java/me/braydon/plugin/GitUtils.java

@@ -0,0 +1,81 @@
+package me.braydon.plugin;
+
+import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.api.errors.GitAPIException;
+import org.eclipse.jgit.internal.storage.file.FileRepository;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevWalk;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.AbstractMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * @author Braydon
+ */
+public final class GitUtils {
+    /**
+     * Can't construct utility classes.
+     */
+    public GitUtils() {
+        throw new UnsupportedOperationException("Cannot instantiate utility class.");
+    }
+    
+    /**
+     * Get the git data for the current repository.
+     * <p>
+     * "Git data" is referred to as the latest commit
+     * hash, as well as the commit depth, or in other
+     * words, the amount of commits since the last tag.
+     * <p>
+     * If successful, a map entry is returned containing
+     * the commit hash as the key, and the commit depth
+     * as the value.
+     * <p>
+     * If there is no local git repository, or
+     * an error has occurred, then null is returned.
+     * </p>
+     *
+     * @return the map entry containing the git data
+     * @see Map.Entry for map entry
+     */
+    public static Map.Entry<String, Integer> getGitData() {
+        File gitDir = new File(".git");
+        if (!gitDir.exists()) { // Not a git repository, return null
+            return null;
+        }
+        try (
+            FileRepository repository = new FileRepository(gitDir); // Create a new file repository
+            Git git = new Git(repository); // Create a new git instance
+            RevWalk walk = new RevWalk(repository); // Create a new rev walk of the repository
+        ) {
+            RevCommit latestCommit = git.log().setMaxCount(1).call().iterator().next(); // Get the latest commit
+            
+            // Find the commits since the last tag
+            int commitsSinceLastTag = 0;
+            List<Ref> tags = git.tagList().call();
+            RevCommit commit = walk.parseCommit(repository.resolve("HEAD"));
+            while (true) {
+                for (Ref tag : tags) {
+                    // If the commit is not the same as the tag, continue
+                    if (!walk.parseCommit(tag.getObjectId()).equals(commit)) {
+                        continue;
+                    }
+                    walk.dispose(); // Dispose of the rev walk
+                    
+                    // Return the git data
+                    return new AbstractMap.SimpleEntry<>(latestCommit.getName(), commitsSinceLastTag);
+                }
+                commitsSinceLastTag++; // Increment commits since last tag
+                commit = walk.parseCommit(commit.getParent(0)); // Get the parent commit
+            }
+        } catch (IOException | GitAPIException ex) {
+            System.err.println("Failed fetching git data:");
+            ex.printStackTrace();
+        }
+        return null;
+    }
+}

src/main/java/me/braydon/plugin/VersioningMojo.java

@@ -12,6 +12,11 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 /**
+ * The purpose of this mojo is to uniquely identify
+ * development builds of projects by modifying the
+ * output jar name to contain a commit depth, as well
+ * as a commit hash.
+ *
  * @author Braydon
  */
 @Mojo(name = "versioning", defaultPhase = LifecyclePhase.GENERATE_SOURCES, threadSafe = true)
@@ -34,22 +39,28 @@ public final class VersioningMojo extends AbstractMojo {
             return;
         }
         String target = matcher.group(); // Extract the found target version
-
+        
         // Fetch git data
         System.out.println("Retrieving git data..."); // Log git data retrieval
         int depth = 0; // The amount of commits since the last tag
         String commitHash = "unknown"; // The commit hash of the current commit
         
+        long before = System.currentTimeMillis(); // The time before retrieving git data
         Map.Entry<String, Integer> gitData = GitUtils.getGitData(); // Get the git data
         if (gitData == null) { // No git data
             System.out.println("Failed to retrieve git data, is this a git repository?");
         } else {
             depth = gitData.getValue(); // Set the depth
-            commitHash = gitData.getKey(); // Set the commit hash
+            commitHash = gitData.getKey().substring(0, 7); // Set the commit hash (trimmed)
+            System.out.println("Commits since last tag (depth): " + depth);
+            System.out.println("Last commit: " + commitHash);
         }
+        System.out.println("Data retrieval took " + (System.currentTimeMillis() - before) + "ms");
         
         // Updating the output jar name
         Build build = project.getBuild(); // Get the build
-        build.setFinalName(build.getFinalName().replace(target, "-dev-" + depth + "-" + commitHash));
+        build.setFinalName(build.getFinalName().replace(target, String.format("-dev-%s-%s",
+            depth, commitHash
+        )));
     }
 }