Related
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 from dependencies to be copied into the jar as well.
Update: I know that I cant just include a jar file in a jar file. I'm searching for a way to unpack the jars that are specified as dependencies, and package the class files into my jar.
You can do this using the maven-assembly plugin with the "jar-with-dependencies" descriptor. Here's the relevant chunk from one of our pom.xml's that does this:
<build>
<plugins>
<!-- any other plugins -->
<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>
</plugins>
</build>
With Maven 2, the right way to do this is to use the Maven2 Assembly Plugin which has a pre-defined descriptor file for this purpose and that you could just use on the command line:
mvn assembly:assembly -DdescriptorId=jar-with-dependencies
If you want to make this jar executable, just add the main class to be run to the plugin configuration:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>my.package.to.my.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
If you want to create that assembly as part of the normal build process, you should bind the single or directory-single goal (the assembly goal should ONLY be run from the command line) to a lifecycle phase (package makes sense), something like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>create-my-bundle</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
...
</configuration>
</execution>
</executions>
</plugin>
Adapt the configuration element to suit your needs (for example with the manifest stuff as spoken).
If you want to do an executable jar file, them need set the main class too. So the full configuration should be.
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
<configuration>
<!-- ... -->
<archive>
<manifest>
<mainClass>fully.qualified.MainClass</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
Method 1: Copy the dependencies' JAR files into target/lib and then add them to the JAR's classpath in MANIFEST:
<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: Unpack all dependencies and repack their classes and resources into one flat JAR. Note: The overlapping resources will be randomly lost!
<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>
There's the shade maven plugin. It can be used to package and rename dependencies (to omit dependency problems on the classpath).
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>
If you (like me) dont particularly like the jar-with-dependencies approach described above,
the maven-solution I prefer is to simply build a WAR-project,
even if it is only a stand-alone java application you are building:
Make a normal maven jar-project, that will build your jar-file (without the dependencies).
Also, setup a maven war-project (with only an empty src/main/webapp/WEB-INF/web.xml file, which will avoid a warning/error in the maven-build), that only has your jar-project as a dependency, and make your jar-project a <module> under your war-project. (This war-project is only a simple trick to wrap all your jar-file dependencies into a zip-file.)
Build the war-project to produce the war-file.
In the deployment-step, simply rename your .war-file to *.zip and unzip it.
You should now have a lib-directory (which you can move where you want it) with your jar and all the dependencies you need to run your application:
java -cp 'path/lib/*' MainClass
(The wildcard in classpath works in Java-6 or higher)
I think this is both simpler to setup in maven (no need to mess around with the assembly plugin) and also gives you a clearer view of the application-structure (you will see the version-numbers of all dependent jars in plain view, and avoid clogging everything into a single jar-file).
http://fiji.sc/Uber-JAR provides an excellent explanation of the alternatives:
There are three common methods for constructing an uber-JAR:
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
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
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.
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>
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
I was trying to do sth similar, but I didn't want all jars to be included. I wanted to include some specific directories from the given dependency. In addition classifier tag was already occupied, so I couldn't do:
<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>
I used maven-dependency-plugin and unpack goal
And unpacked what I wanted to the ${project.build.directory}/classes, otherwise it will be omitted
Because it was in the classes directory, maven finally placed it in the jar
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>unpack</id>
<phase>prepare-package</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>my.group</groupId>
<artifactId>my.artifact</artifactId>
<classifier>occupied</classifier>
<version>1.0</version>
<type>jar</type>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
<includes>aaa/**, bbb/**, ccc/**</includes>
</configuration>
</execution>
</executions>
</plugin>
This post may be a bit old, but I also had the same problem recently. The first solution proposed by John Stauffer is a good one, but I had some problems as I am working this spring. The spring's dependency-jars I use have some property files and xml-schemas declaration which share the same paths and names. Although these jars come from the same versions, the jar-with-dependencies maven-goal was overwriting theses file with the last file found.
In the end, the application was not able to start as the spring jars could not find the correct properties files. In this case the solution propose by Rop have solved my problem.
Also since then, the spring-boot project now exist. It has a very cool way to manage this problem by providing a maven goal which overload the package goal and provide its own class loader. See spring-boots Reference Guide
Have a look at this answer:
I am creating an installer that runs as a Java JAR file and it needs to unpack WAR and JAR files into appropriate places in the installation directory. The dependency plugin can be used in the package phase with the copy goal and it will download any file in the Maven repository (including WAR files) and write them where ever you need them. I changed the output directory to ${project.build.directory}/classes and then end result is that the normal JAR task includes my files just fine. I can then extract them and write them into the installation directory.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>getWar</id>
<phase>package</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>the.group.I.use</groupId>
<artifactId>MyServerServer</artifactId>
<version>${env.JAVA_SERVER_REL_VER}</version>
<type>war</type>
<destFileName>myWar.war</destFileName>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
</configuration>
</execution>
</executions>
Thanks
I have added below snippet in POM.xml file and Mp problem resolved and
create fat jar file that include all dependent jars.
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
<configuration>
<descriptorRefs>
<descriptorRef>dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
I found this to be the clearest answer; other answers here were missing things that weren't obvious to me such as mvn clean package command for example, and adding the plugin separately as a dependancy also. All of which are probably obvious to more habitual maven users.
https://howtodoinjava.com/maven/executable-jar-with-dependencies/
To make it more simple, You can use the below plugin.
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<classifier>spring-boot</classifier>
<mainClass>
com.nirav.certificate.CertificateUtility
</mainClass>
</configuration>
</execution>
</executions>
</plugin>
I am using eclipse with maven. I need to combine several class-files in a jar while building the project with maven.
so i added the following to the pom.xml:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.4</version>
<configuration>
<archive>
<index>false</index>
<classesDirectory>${project.build.classes.de.filter}</classesDirectory>
<finalName>BasicFilters</finalName>
<outputDirectory>${project.build.Plugins}</outputDirectory>
</archive>
</configuration>
<executions>
<execution>
<id>Building Jar from Filters</id>
<phase>package</phase>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
The building says: build success, but it does not built any jar and no info from the plugin is displayed in the console.
Use mvn package to create a .jar file provided you have the right configurations. Read this link. Here, you have a good tutorial link
I'm trying to create automated solution for building with maven. My vision is to have a Maven build, which creates JAR file from my project and then just copies all the dependencies as JARs to some sub-directory in "target" folder.
I do not want to use Shade or Assembly (so I do not want to extract the content of other JARs and include it in one "super-JAR", because the project is more complicated and it breaks when I'm including all the JARs in one file).
How can I do such build POM?
I don't see here any problem. Just create maven pom.xml with <packaging>jar</packaging>
By default it should not pack into your jar all dependent libraries.
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<phase>install</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
Related with your latest comment, use this plugin to add the main class in the manifest:
<plugin>
<!-- Build an executable JAR -->
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>com.test.YourMainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
You can use the maven-assembly-plugin to create a .zip file from a selection of other files in your directory. I have used this method to create distribution zip files for a project. There are several examples available in the maven-assembly-plugin documentation.
i am creating a standalone java application with maven, and i am including the dependencies in the jar file with maven-dependecy-plugin as follows:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>prepare-package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/classes/lib</outputDirectory>
<overWriteReleases>false</overWriteReleases>
<overWriteSnapshots>false</overWriteSnapshots>
<overWriteIfNewer>true</overWriteIfNewer>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>theMainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>create-my-bundle</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</execution>
</executions>
</plugin>
this includes the dependencies in the generated jar file in a lib folder, and the jar runs and works fine, but the issue is in the other generated jar file appname-1.0-jar-with-dependencies.jar.
ISSUE: i am not sure if it's an issue or not, but i noticed in target folder in the generated appname-1.0-jar-with-dependencies.jar, that it contains duplicate application files like:
all sql,property files,xml files exists twice.
all java classes .class file exists twice.
there are lots of overview.html and license.txt files related to the dependencies.
i am not sure if that's feels right or not, also i need someone to clarify for me what is the importance of this generated jar file, since i am not familiar with this plugin.
please advise, thanks.
Since you have mentioned jar-with-dependencies, I assume you are using maven assembly plugin to assemble your project artifacts along with the dependant jars into a single jar.
I suspect that your project artifacts are getting into the jar-with-dependencies twice - due to a property useProjectArtifact of dependencySet which is true, by default. You can set this property to true in your assembly descriptor and see if it addresses your issue.
In the specific case above, maven dependency plugin does not seem to be doing anything useful. maven assembly plugin automatically packages all its dependencies into a single distribution as per configuration.
But do note classpath issues if you create an executable jar-with-dependencies. You may want to create a zip or tar.gz instead.
The configuration used above is the default and does not allow for customization. You may want to use an assembly descriptor file, where you can set the property mentioned earlier or other options.
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 from dependencies to be copied into the jar as well.
Update: I know that I cant just include a jar file in a jar file. I'm searching for a way to unpack the jars that are specified as dependencies, and package the class files into my jar.
You can do this using the maven-assembly plugin with the "jar-with-dependencies" descriptor. Here's the relevant chunk from one of our pom.xml's that does this:
<build>
<plugins>
<!-- any other plugins -->
<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>
</plugins>
</build>
With Maven 2, the right way to do this is to use the Maven2 Assembly Plugin which has a pre-defined descriptor file for this purpose and that you could just use on the command line:
mvn assembly:assembly -DdescriptorId=jar-with-dependencies
If you want to make this jar executable, just add the main class to be run to the plugin configuration:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<archive>
<manifest>
<mainClass>my.package.to.my.MainClass</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
If you want to create that assembly as part of the normal build process, you should bind the single or directory-single goal (the assembly goal should ONLY be run from the command line) to a lifecycle phase (package makes sense), something like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>create-my-bundle</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
...
</configuration>
</execution>
</executions>
</plugin>
Adapt the configuration element to suit your needs (for example with the manifest stuff as spoken).
If you want to do an executable jar file, them need set the main class too. So the full configuration should be.
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
<configuration>
<!-- ... -->
<archive>
<manifest>
<mainClass>fully.qualified.MainClass</mainClass>
</manifest>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
</plugins>
Method 1: Copy the dependencies' JAR files into target/lib and then add them to the JAR's classpath in MANIFEST:
<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: Unpack all dependencies and repack their classes and resources into one flat JAR. Note: The overlapping resources will be randomly lost!
<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>
There's the shade maven plugin. It can be used to package and rename dependencies (to omit dependency problems on the classpath).
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>
If you (like me) dont particularly like the jar-with-dependencies approach described above,
the maven-solution I prefer is to simply build a WAR-project,
even if it is only a stand-alone java application you are building:
Make a normal maven jar-project, that will build your jar-file (without the dependencies).
Also, setup a maven war-project (with only an empty src/main/webapp/WEB-INF/web.xml file, which will avoid a warning/error in the maven-build), that only has your jar-project as a dependency, and make your jar-project a <module> under your war-project. (This war-project is only a simple trick to wrap all your jar-file dependencies into a zip-file.)
Build the war-project to produce the war-file.
In the deployment-step, simply rename your .war-file to *.zip and unzip it.
You should now have a lib-directory (which you can move where you want it) with your jar and all the dependencies you need to run your application:
java -cp 'path/lib/*' MainClass
(The wildcard in classpath works in Java-6 or higher)
I think this is both simpler to setup in maven (no need to mess around with the assembly plugin) and also gives you a clearer view of the application-structure (you will see the version-numbers of all dependent jars in plain view, and avoid clogging everything into a single jar-file).
http://fiji.sc/Uber-JAR provides an excellent explanation of the alternatives:
There are three common methods for constructing an uber-JAR:
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
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
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.
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>
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
I was trying to do sth similar, but I didn't want all jars to be included. I wanted to include some specific directories from the given dependency. In addition classifier tag was already occupied, so I couldn't do:
<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>
I used maven-dependency-plugin and unpack goal
And unpacked what I wanted to the ${project.build.directory}/classes, otherwise it will be omitted
Because it was in the classes directory, maven finally placed it in the jar
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>unpack</id>
<phase>prepare-package</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>my.group</groupId>
<artifactId>my.artifact</artifactId>
<classifier>occupied</classifier>
<version>1.0</version>
<type>jar</type>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
<includes>aaa/**, bbb/**, ccc/**</includes>
</configuration>
</execution>
</executions>
</plugin>
This post may be a bit old, but I also had the same problem recently. The first solution proposed by John Stauffer is a good one, but I had some problems as I am working this spring. The spring's dependency-jars I use have some property files and xml-schemas declaration which share the same paths and names. Although these jars come from the same versions, the jar-with-dependencies maven-goal was overwriting theses file with the last file found.
In the end, the application was not able to start as the spring jars could not find the correct properties files. In this case the solution propose by Rop have solved my problem.
Also since then, the spring-boot project now exist. It has a very cool way to manage this problem by providing a maven goal which overload the package goal and provide its own class loader. See spring-boots Reference Guide
Have a look at this answer:
I am creating an installer that runs as a Java JAR file and it needs to unpack WAR and JAR files into appropriate places in the installation directory. The dependency plugin can be used in the package phase with the copy goal and it will download any file in the Maven repository (including WAR files) and write them where ever you need them. I changed the output directory to ${project.build.directory}/classes and then end result is that the normal JAR task includes my files just fine. I can then extract them and write them into the installation directory.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>getWar</id>
<phase>package</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>the.group.I.use</groupId>
<artifactId>MyServerServer</artifactId>
<version>${env.JAVA_SERVER_REL_VER}</version>
<type>war</type>
<destFileName>myWar.war</destFileName>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
</configuration>
</execution>
</executions>
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>
I found this to be the clearest answer; other answers here were missing things that weren't obvious to me such as mvn clean package command for example, and adding the plugin separately as a dependancy also. All of which are probably obvious to more habitual maven users.
https://howtodoinjava.com/maven/executable-jar-with-dependencies/
To make it more simple, You can use the below plugin.
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
<configuration>
<classifier>spring-boot</classifier>
<mainClass>
com.nirav.certificate.CertificateUtility
</mainClass>
</configuration>
</execution>
</executions>
</plugin>