To include external jars you can add the dependency with System scope.
<dependency>
..
<scope>system<scope>
<systemPath>your jar path</systemPath>
</dependency>
Also you can define your compiler plugin to include the directory in your classpath.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<includes>
<include>directory path/*.jar</include>
</includes>
</configuration>
</plugin>
</plugins>
</build>
NOTE: This will make your build success. But not sure how to make those classes available for access inside IDE.
Answer from Rima on Stack Overflowjava - How to put a jar in classpath in Eclipse? - Stack Overflow
How do I add jar files to classpath? Specifically, I am using Eclipse and I want to add Quartz scheduler jar files
maven - how to add my external jar file to class path - Stack Overflow
Maven: add a folder or jar file into current classpath - Stack Overflow
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Right click on the project in which you want to put jar file. A window will open like this
Click on the AddExternal Jars there you can give the path to that jar file
As of rev 17 of the Android Developer Tools, the correct way to add a library jar when.using the tools and Eclipse is to create a directory called libs on the same level as your src and assets directories and then drop the jar in there. Nothing else.required, the tools take care of all the rest for you automatically.
Maven out of the box will come up with a JAR file (default packaging). This JAR file only contains (main) artifacts of the project. If you take just that and run it, clearly the dependencies are missing -- by design.
Typically Maven artifacts are reused in combination with their POM so that at the point of use it's know what the dependencies are. Edit: if you're using APKs and installing them on a phone, there may be mechanisms to deal with dependencies, I'm answering this merely from a Maven standpoint.
If you want to create a JAR with dependencies you have to tell Maven to do so, that's not the default. Ways of having Maven do that are (probably not exhaustive):
Maven Assembly plugin,
jar-with-dependenciespredefined descriptor:<plugin> <artifactId>maven-assembly-plugin</artifactId> <version>2.4</version> <configuration> <descriptorRefs> <descriptorRef>jar-with-dependencies</descriptorRef> </descriptorRefs> </configuration> ...Maven Shade plugin
That way it'll create a single-jar of large size and build time will be large everytime you try to build.
I instead prefer adding all jars to a lib folder and including in the classpath (jar's manifest), because of which when we have to make some change or redeploy to the client or some place, we can simply give the small jar (not all the dependencies merged within jar)
<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>
<mainClass>com.kalindiinfotech.webcrawler.MainGUI</mainClass>
<!-- <mainClass>com.KalindiInfotech.busbookingmaven.form.LoginForm</mainClass>-->
</manifest>
</archive>
</configuration>
</plugin>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<phase>install</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
This might have been asked before. See Can I add jars to maven 2 build classpath without installing them?
In a nutshell: include your jar as dependency with system scope. This requires specifying the absolute path to the jar.
See also http://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html
The classpath setting of the compiler plugin are two args. Changed it like this and it worked for me:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.1</version>
<configuration>
<compilerArgs>
<arg>-cp</arg>
<arg>${cp}:${basedir}/lib/bad.jar</arg>
</compilerArgs>
</configuration>
</plugin>
I used the gmavenplus-plugin to read the path and create the property 'cp':
<plugin>
<!--
Use Groovy to read classpath and store into
file named value of property <cpfile>
In second step use Groovy to read the contents of
the file into a new property named <cp>
In the compiler plugin this is used to create a
valid classpath
-->
<groupId>org.codehaus.gmavenplus</groupId>
<artifactId>gmavenplus-plugin</artifactId>
<version>1.12.0</version>
<dependencies>
<dependency>
<groupId>org.codehaus.groovy</groupId>
<artifactId>groovy-all</artifactId>
<!-- any version of Groovy \>= 1.5.0 should work here -->
<version>3.0.6</version>
<type>pom</type>
<scope>runtime</scope>
</dependency>
</dependencies>
<executions>
<execution>
<id>read-classpath</id>
<phase>validate</phase>
<goals>
<goal>execute</goal>
</goals>
</execution>
</executions>
<configuration>
<scripts>
<script><![CDATA[
def file = new File(project.properties.cpfile)
/* create a new property named 'cp'*/
project.properties.cp = file.getText()
println '<<< Retrieving classpath into new property named <cp> >>>'
println 'cp = ' + project.properties.cp
]]></script>
</scripts>
</configuration>
</plugin>
Problems of popular approaches
Most of the answers you'll find around the internet will suggest you to either install the dependency to your local repository or specify a "system" scope in the pom and distribute the dependency with the source of your project. But both of these solutions are actually flawed.
Why you shouldn't apply the "Install to Local Repository" approach
When you install a dependency to your local repository it remains there. Your distribution artifact will do fine as long as it has access to this repository. The problem is in most cases this repository will reside on your local machine, so there'll be no way to resolve this dependency on any other machine. Clearly making your artifact depend on a specific machine is not a way to handle things. Otherwise this dependency will have to be locally installed on every machine working with that project which is not any better.
Why you shouldn't apply the "System Scope" approach
The JAR files you depend on with the "System Scope" approach neither get installed to any repository or attached to your target packages. That's why your distribution package won't have a way to resolve that dependency when used. That I believe was the reason why the use of system scope even got deprecated. Anyway you don't want to rely on a deprecated feature.
The static in-project repository solution
After putting this in your POM file:
<repository>
<id>repo</id>
<releases>
<enabled>true</enabled>
<checksumPolicy>ignore</checksumPolicy>
</releases>
<snapshots>
<enabled>false</enabled>
</snapshots>
<url>file://${project.basedir}/repo</url>
</repository>
for each artifact with a group id of form x.y.z Maven will include the following location inside your project directory in its search for artifacts:
repo/
| - x/
| | - y/
| | | - z/
| | | | - ${artifactId}/
| | | | | - ${version}/
| | | | | | - ${artifactId}-${version}.jar
To elaborate more on this, you can read this blog post.
Use Maven to install to project repository
Instead of creating this structure by hand, I recommend to use a Maven plugin to install your JAR files as artifacts. So, to install an artifact to an in-project repository under repo folder execute:
mvn install:install-file -DlocalRepositoryPath=repo -DcreateChecksum=true -Dpackaging=jar -Dfile=[your-jar] -DgroupId=[...] -DartifactId=[...] -Dversion=[...]
If you'll choose this approach, you'll be able to simplify the repository declaration in the POM file to:
<repository>
<id>repo</id>
<url>file://${project.basedir}/repo</url>
</repository>
A helper script
Since executing installation command for each library is kind of annoying and definitely error-prone, I've created a utility script which automatically installs all the JAR files from a lib folder to a project repository, while automatically resolving all metadata (groupId, artifactId, etc.) from names of files. The script also prints out the dependencies XML file for you to copy-paste in your POM file.
Include the dependencies in your target package
When you'll have your in-project repository created, you'll have solved a problem of distributing the dependencies of the project with its source, but since then your project's target artifact will depend on non-published JAR files, so when you'll install it to a repository, it will have unresolvable dependencies.
To beat this problem, I suggest to include these dependencies in your target package. This you can do with either the Assembly Plugin or better with the OneJar Plugin. The official documentation on OneJar is easy to grasp.
For throwaway code only
Set scope == system and just make up a groupId, artifactId, and version:
<dependency>
<groupId>org.swinglabs</groupId>
<artifactId>swingx</artifactId>
<version>0.9.2</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/swingx-0.9.3.jar</systemPath>
</dependency>
Note: System dependencies are not copied into the resulting JAR/WAR file (see How to include system dependencies in a WAR file built using Maven)