Including dependencies in a jar with Maven

Question

Is there a way to force maven(2.0.9) to include all the dependencies in a single jar file?

I have a project the builds into a single jar file. I want the classes fro

Answer 1

Putting Maven aside, you can put JAR libraries inside the Main Jar but you will need to use your own classloader.

Check this project: One-JAR link text

Answer 2

Thanks I have added below snippet in POM.xml file and Mp problem resolved and create fat jar file that include all dependent jars.

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
        <executions>
            <execution>
                <phase>package</phase>
                <goals>
                    <goal>single</goal>
                </goals>
            </execution>
        </executions>
        <configuration>
            <descriptorRefs>
                <descriptorRef>dependencies</descriptorRef>
            </descriptorRefs>
        </configuration>
    </plugin>
</plugins>

Answer 3

You can use the newly created jar using a <classifier> tag.

<dependencies>
    <dependency>
        <groupId>your.group.id</groupId>
        <artifactId>your.artifact.id</artifactId>
        <version>1.0</version>
        <type>jar</type>
        <classifier>jar-with-dependencies</classifier>
    </dependency>
</dependencies>

Answer 4

http://fiji.sc/Uber-JAR provides an excellent explanation of the alternatives:

There are three common methods for constructing an uber-JAR:

1. Unshaded. Unpack all JAR files, then repack them into a single JAR.
   • Pro: Works with Java's default class loader.
   • Con: Files present in multiple JAR files with the same path (e.g., META-INF/services/javax.script.ScriptEngineFactory) will overwrite one another, resulting in faulty behavior.
   • Tools: Maven Assembly Plugin, Classworlds Uberjar
2. Shaded. Same as unshaded, but rename (i.e., "shade") all packages of all dependencies.
   • Pro: Works with Java's default class loader. Avoids some (not all) dependency version clashes.
   • Con: Files present in multiple JAR files with the same path (e.g., META-INF/services/javax.script.ScriptEngineFactory) will overwrite one another, resulting in faulty behavior.
   • Tools: Maven Shade Plugin
3. JAR of JARs. The final JAR file contains the other JAR files embedded within.
   • Pro: Avoids dependency version clashes. All resource files are preserved.
   • Con: Needs to bundle a special "bootstrap" classloader to enable Java to load classes from the wrapped JAR files. Debugging class loader issues becomes more complex.
   • Tools: Eclipse JAR File Exporter, One-JAR.

Answer 5

        <!-- Method 1 -->
        <!-- Copy dependency libraries jar files to a separated LIB folder -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <configuration>
                <outputDirectory>${project.build.directory}/lib</outputDirectory>
                <excludeTransitive>false</excludeTransitive> 
                <stripVersion>false</stripVersion>
            </configuration>
            <executions>
                <execution>
                    <id>copy-dependencies</id>
                    <phase>package</phase>
                    <goals>
                        <goal>copy-dependencies</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
        <!-- Add LIB folder to classPath -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <version>2.4</version>
            <configuration>
                <archive>
                    <manifest>
                        <addClasspath>true</addClasspath>
                        <classpathPrefix>lib/</classpathPrefix>
                    </manifest>
                </archive>
            </configuration>
        </plugin>


        <!-- Method 2 -->
        <!-- Package all libraries classes into one runnable jar -->
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <executions>
              <execution>
                <phase>package</phase>
                <goals>
                  <goal>single</goal>
                </goals>
              </execution>
            </executions>
            <configuration>
              <descriptorRefs>
                <descriptorRef>jar-with-dependencies</descriptorRef>
              </descriptorRefs>
            </configuration>
        </plugin>            

Answer 6

My definitive solution on Eclipse Luna and m2eclipse: Custom Classloader (download and add to your project, 5 classes only) :http://git.eclipse.org/c/jdt/eclipse.jdt.ui.git/plain/org.eclipse.jdt.ui/jar%20in%20jar%20loader/org/eclipse/jdt/internal/jarinjarloader/; this classloader is very best of one-jar classloader and very fast;

<project.mainClass>org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader</project.mainClass> <project.realMainClass>my.Class</project.realMainClass>

Edit in JIJConstants "Rsrc-Class-Path" to "Class-Path"
mvn clean dependency:copy-dependencies package
is created a jar with dependencies in lib folder with a thin classloader

<build>
    <resources>
        <resource>
            <directory>src/main/java</directory>
            <includes>
                <include>**/*.java</include>
                <include>**/*.properties</include>
            </includes>
        </resource>
        <resource>
            <directory>src/main/resources</directory>
            <filtering>true</filtering>
            <includes>
                <include>**/*</include>
            </includes>
            <targetPath>META-INF/</targetPath>
        </resource>
        <resource>
            <directory>${project.build.directory}/dependency/</directory>
            <includes>
                <include>*.jar</include>
            </includes>
            <targetPath>lib/</targetPath>
        </resource>
    </resources>
<pluginManagement>
        <plugins>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <mainClass>${project.mainClass}</mainClass>
                            <classpathPrefix>lib/</classpathPrefix>
                        </manifest>

                        <manifestEntries>
                            <Rsrc-Main-Class>${project.realMainClass}  </Rsrc-Main-Class>
                            <Class-Path>./</Class-Path>
                        </manifestEntries>

                    </archive>
                </configuration>
            </plugin>
<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-dependencies</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </pluginManagement>
</build>