Maven , How to add dependency of local system java-source? - java

I want to build one jar that includes a child module which depends on other package of my own project.
The output one jar should include all the related class (both from jar and my own project's classes).So the child module's classes is the base classes that should be included in the output jar,and these import some classes of my own project.All the related classes in my own project should be included.
for more detail please visit How to automatically collect all related class into one jar (use maven)?
Here is what I already find:
<project>
<dependencies>
<dependency>
<scope>system</scope>
<systemPath>D:\how\to\write</systemPath>
<groupId>how.to.write</groupId>
<artifactId>how-to-write</artifactId>
<version>0.0.1-SNAPSHOT</version>
<type>java-source</type>
</dependency>
</dependencies>
</project>
The error message is : Could not find artifact how.to.write:how-to-write:jar:sources:0.0.1-SNAPSHOT at specified path D:\how\to\write
the path D:\how\to\write contains my own project's classes that could support the build

Your maven dependency will look for a jar file with name how.to.write:how-to-write:jar:sources:0.0.1-SNAPSHOT in D:\how\to\write directory. Since you do not have one, the build will fail.
If your own project does not use maven, then you should create a jar file and place it in D:\how\to\write location and rename it to how.to.write:how-to-write:jar:sources:0.0.1-SNAPSHOT. Then your build mvn clean install will be success.
The command for creating jar file is jar cf jar-file input-file(s).
Have a look at this page on how to create a jar file

Related

Resolving Dependency from Github using Ivy.xml

I have a github repo that I created a Release for. While creating the release I manually added a .jar file. Lets call it exampleLibrary.jar
This would be github.com/MyExampleRepo/Releases
I have a project I want to add a dependency for to use this exampleLibrary.jar file I added in my release v1.0
This project using Ivy.xml for resolving dependencies.
To get the jar from github using maven with pom.xml I imagine it would look something like this:
<dependency>
<groupId>com.github.User</groupId>
<artifactId>Repo name</artifactId>
<version>Release tag</version>
</dependency>
How would I do this using Ivy.xml? This is what I have tried:
<dependency org="com.github" name="MyExampleRepo" rev="v1.0"/>

Maven- Could not resolve dependency

I am a beginner in using Maven.. I tried to add Grobid (for pdf parsing) in maven. The dependency I gave is :
<dependency>
<groupId>org.grobid</groupId>
<artifactId>grobid-core</artifactId>
<version>0.3.4</version>
</dependency>
But on building the pom it shows the following error:
[ERROR] Failed to execute goal on project Miner: Could not resolve dependencies for project Miner:war:1.0-SNAPSHOT: Failed to collect dependencies at org.grobid:grobid-core:jar:0.3.4 -> org.chasen:crfpp:jar:1.0.2: Failed to read artifact descriptor for org.chasen:crfpp:jar:1.0.2: Could not transfer artifact org.chasen:crfpp:pom:1.0.2 from/to 3rd-party-local-repo (file:///${basedir}/lib/): Repository path /${basedir}/lib does not exist, and cannot be created. -> [Help 1]
I have gone through different questions related..I tried after adding pom etc. Still it is not working.. why this error comes..do we have to do extra codes for Grobid..?
add the below repository in pom or .m2/settings.xml
<repositories>
<repository>
<id>Grobid repository</id>
<url>https://mvnrepository.com/artifact/org.grobid/grobid-core</url>
</repository>
</repositories>
Start by downloading maven from http://mirror.vorboss.net/apache/maven/maven-3/3.3.9/binaries/apache-maven-3.3.9-bin.zip
Unzip it somewhere, then assuming your're on windows
1) set an environment variable M2_HOME to point at the unziped folder.
2) add %M2_HOME%/bin to your PATH environment variable
3) go to your home directory (probably C:/Users/????? and create a .m2 folder
4) move the settings.xml file from the maven unzippped/conf directory to the directory created in step 3.
5) you may have to set the proxy element correctly in your settings.xml file
It should work.
You might be new to maven, but it explicit the problem here:
Repository path /${basedir}/lib does not exist, and cannot be created.
This means that Maven could not locate the repository path you are trying to access. Or (from the "cannot be created") can't find the directory where to save the content.
As you did not provide pom.xml to look further, you'll have to find all ${basedir}/lib path in your pom.xml and in your maven settings (default to %USERPROFILE%/.m2/settings.xml or $HOME/.m2/settings.xml), then you may want to
try with an absolute path.
use an actual HTTP repository where that dependency and child' dependencies are.
use a repository server such as Sonatype Nexus or Archiva and provide a mirror/copy of it.

Manually create jar for use with maven [duplicate]

Maven 2 is driving me crazy during the experimentation / quick and dirty mock-up phase of development.
I have a pom.xml file that defines the dependencies for the web-app framework I want to use, and I can quickly generate starter projects from that file. However, sometimes I want to link to a 3rd party library that doesn't already have a pom.xml file defined, so rather than create the pom.xml file for the 3rd party lib by hand and install it, and add the dependency to my pom.xml, I would just like to tell Maven: "In addition to my defined dependencies, include any jars that are in /lib too."
It seems like this ought to be simple, but if it is, I am missing something.
Any pointers on how to do this are greatly appreciated. Short of that, if there is a simple way to point maven to a /lib directory and easily create a pom.xml with all the enclosed jars mapped to a single dependency which I could then name / install and link to in one fell swoop would also suffice.
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 Repo" 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 jars 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:
<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 dir 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 repo
Instead of creating this structure by hand I recommend to use a Maven plugin to install your jars 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 pom to:
<repository>
<id>repo</id>
<url>file://${project.basedir}/repo</url>
</repository>
A helper script
Since executing installation command for each lib is kinda annoying and definitely error prone, I've created a utility script which automatically installs all the jars from a lib folder to a project repository, while automatically resolving all metadata (groupId, artifactId and etc.) from names of files. The script also prints out the dependencies xml for you to copy-paste in your pom.
Include the dependencies in your target package
When you'll have your in-project repository created you'll have solved a problem of distributing the dependencies of the project with its source, but since then your project's target artifact will depend on non-published jars, so when you'll install it to a repository it will have unresolvable dependencies.
To beat this problem I suggest to include these dependencies in your target package. This you can do with either the Assembly Plugin or better with the OneJar Plugin. The official documentaion on OneJar is easy to grasp.
For throw away code only
set scope == system and just make up a groupId, artifactId, and version
<dependency>
<groupId>org.swinglabs</groupId>
<artifactId>swingx</artifactId>
<version>0.9.2</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/swingx-0.9.3.jar</systemPath>
</dependency>
Note: system dependencies are not copied into resulted jar/war
(see How to include system dependencies in war built using maven)
You may create local repository on your project
For example if you have libs folder in project structure
In libs folder you should create directory structure like: /groupId/artifactId/version/artifactId-version.jar
In your pom.xml you should register repository
<repository>
<id>ProjectRepo</id>
<name>ProjectRepo</name>
<url>file://${project.basedir}/libs</url>
</repository>
and add dependency as usual
<dependency>
<groupId>groupId</groupId>
<artifactId>artifactId</artifactId>
<version>version</version>
</dependency>
That is all.
For detailed information: How to add external libraries in Maven (archived)
Note: When using the System scope (as mentioned on this page), Maven needs absolute paths.
If your jars are under your project's root, you'll want to prefix your systemPath values with ${basedir}.
This is what I have done, it also works around the package issue and it works with checked out code.
I created a new folder in the project in my case I used repo, but feel free to use src/repo
In my POM I had a dependency that is not in any public maven repositories
<dependency>
<groupId>com.dovetail</groupId>
<artifactId>zoslog4j</artifactId>
<version>1.0.1</version>
<scope>runtime</scope>
</dependency>
I then created the following directories repo/com/dovetail/zoslog4j/1.0.1 and copied the JAR file into that folder.
I created the following POM file to represent the downloaded file (this step is optional, but it removes a WARNING) and helps the next guy figure out where I got the file to begin with.
<?xml version="1.0" encoding="UTF-8" ?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.dovetail</groupId>
<artifactId>zoslog4j</artifactId>
<packaging>jar</packaging>
<version>1.0.1</version>
<name>z/OS Log4J Appenders</name>
<url>http://dovetail.com/downloads/misc/index.html</url>
<description>Apache Log4j Appender for z/OS Logstreams, files, etc.</description>
</project>
Two optional files I create are the SHA1 checksums for the POM and the JAR to remove the missing checksum warnings.
shasum -b < repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.jar \
> repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.jar.sha1
shasum -b < repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.pom \
> repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.pom.sha1
Finally I add the following fragment to my pom.xml that allows me to refer to the local repository
<repositories>
<repository>
<id>project</id>
<url>file:///${basedir}/repo</url>
</repository>
</repositories>
This is how we add or install a local jar
<dependency>
<groupId>org.example</groupId>
<artifactId>iamajar</artifactId>
<version>1.0</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/iamajar.jar</systemPath>
</dependency>
i gave some default groupId and artifactId because they are mandatory :)
You really ought to get a framework in place via a repository and identifying your dependencies up front. Using the system scope is a common mistake people use, because they "don't care about the dependency management." The trouble is that doing this you end up with a perverted maven build that will not show maven in a normal condition. You would be better off following an approach like this.
Maven install plugin has command line usage to install a jar into the local repository, POM is optional but you will have to specify the GroupId, ArtifactId, Version and Packaging (all the POM stuff).
Using <scope>system</scope> is a terrible idea for reasons explained by others, installing the file manually to your local repository makes the build unreproducible, and using <url>file://${project.basedir}/repo</url> is not a good idea either because (1) that may not be a well-formed file URL (e.g. if the project is checked out in a directory with unusual characters), (2) the result is unusable if this project’s POM is used as a dependency of someone else’s project.
Assuming you are unwilling to upload the artifact to a public repository, Simeon’s suggestion of a helper module does the job. But there is an easier way now…
The Recommendation
Use non-maven-jar-maven-plugin. Does exactly what you were asking for, with none of the drawbacks of the other approaches.
I found another way to do this, see here from a Heroku post
To summarize (sorry about some copy & paste)
Create a repo directory under your root folder:
yourproject
+- pom.xml
+- src
+- repo
Run this to install the jar to your local repo directory
mvn deploy:deploy-file -Durl=file:///path/to/yourproject/repo/ -Dfile=mylib-1.0.jar -DgroupId=com.example -DartifactId=mylib -Dpackaging=jar -Dversion=1.0
Add this your pom.xml:
<repositories>
<!--other repositories if any-->
<repository>
<id>project.local</id>
<name>project</name>
<url>file:${project.basedir}/repo</url>
</repository>
</repositories>
<dependency>
<groupId>com.example</groupId>
<artifactId>mylib</artifactId>
<version>1.0</version>
</dependency>
What seems simplest to me is just configure your maven-compiler-plugin to include your custom jars. This example will load any jar files in a lib directory.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<includes>
<include>lib/*.jar</include>
</includes>
</configuration>
</plugin>
After having really long discussion with CloudBees guys about properly maven packaging of such kind of JARs, they made an interesting good proposal for a solution:
Creation of a fake Maven project which attaches a pre-existing JAR as a primary artifact, running into belonged POM install:install-file execution. Here is an example of such kinf of POM:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-install-plugin</artifactId>
<version>2.3.1</version>
<executions>
<execution>
<id>image-util-id</id>
<phase>install</phase>
<goals>
<goal>install-file</goal>
</goals>
<configuration>
<file>${basedir}/file-you-want-to-include.jar</file>
<groupId>${project.groupId}</groupId>
<artifactId>${project.artifactId}</artifactId>
<version>${project.version}</version>
<packaging>jar</packaging>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
But in order to implement it, existing project structure should be changed. First, you should have in mind that for each such kind of JAR there should be created different fake Maven project (module). And there should be created a parent Maven project including all sub-modules which are : all JAR wrappers and existing main project. The structure could be :
root project (this contains the parent POM file includes all sub-modules with module XML element) (POM packaging)
JAR 1 wrapper Maven child project (POM packaging)
JAR 2 wrapper Maven child project (POM packaging)
main existing Maven child project (WAR, JAR, EAR .... packaging)
When parent running via mvn:install or mvn:packaging is forced and sub-modules will be executed. That could be concerned as a minus here, since project structure should be changed, but offers a non static solution at the end
The problem with systemPath is that the dependencies' jars won't get distributed along your artifacts as transitive dependencies. Try what I've posted here: Is it best to Mavenize your project jar files or put them in WEB-INF/lib?
Then declare dependencies as usual.
And please read the footer note.
If you want a quick and dirty solution, you can do the following (though I do not recommend this for anything except test projects, maven will complain in length that this is not proper).
Add a dependency entry for each jar file you need, preferably with a perl script or something similar and copy/paste that into your pom file.
#! /usr/bin/perl
foreach my $n (#ARGV) {
$n=~s#.*/##;
print "<dependency>
<groupId>local.dummy</groupId>
<artifactId>$n</artifactId>
<version>0.0.1</version>
<scope>system</scope>
<systemPath>\${project.basedir}/lib/$n</systemPath>
</dependency>
";
A quick&dirty batch solution (based on Alex's answer):
libs.bat
#ECHO OFF
FOR %%I IN (*.jar) DO (
echo ^<dependency^>
echo ^<groupId^>local.dummy^</groupId^>
echo ^<artifactId^>%%I^</artifactId^>
echo ^<version^>0.0.1^</version^>
echo ^<scope^>system^</scope^>
echo ^<systemPath^>${project.basedir}/lib/%%I^</systemPath^>
echo ^</dependency^>
)
Execute it like this: libs.bat > libs.txt.
Then open libs.txt and copy its content as dependencies.
In my case, I only needed the libraries to compile my code, and this solution was the best for that purpose.
To install the 3rd party jar which is not in maven repository use maven-install-plugin.
Below are steps:
Download the jar file manually from the source (website)
Create a folder and place your jar file in it
Run the below command to install the 3rd party jar in your local maven repository
mvn install:install-file -Dfile= -DgroupId=
-DartifactId= -Dversion= -Dpackaging=
Below is the e.g one I used it for simonsite log4j
mvn install:install-file
-Dfile=/Users/athanka/git/MyProject/repo/log4j-rolling-appender.jar -DgroupId=uk.org.simonsite -DartifactId=log4j-rolling-appender -Dversion=20150607-2059 -Dpackaging=jar
In the pom.xml include the dependency as below
<dependency>
<groupId>uk.org.simonsite</groupId>
<artifactId>log4j-rolling-appender</artifactId>
<version>20150607-2059</version>
</dependency>
Run the mvn clean install command to create your packaging
Below is the reference link:
https://maven.apache.org/guides/mini/guide-3rd-party-jars-local.html
A strange solution I found:
using Eclipse
create simple (non-maven) java project
add a Main class
add all the jars to the classpath
export Runnable JAR (it's important, because no other way here to do it)
select Extract required libraries into generated JAR
decide the licence issues
tadammm...install the generated jar to your m2repo
add this single dependency to your other projects.
cheers,
Balint
Even though it does not exactly fit to your problem, I'll drop this here. My requirements were:
Jars that can not be found in an online maven repository should be in the SVN.
If one developer adds another library, the other developers should not be bothered with manually installing them.
The IDE (NetBeans in my case) should be able find the sources and javadocs to provide autocompletion and help.
Let's talk about (3) first: Just having the jars in a folder and somehow merging them into the final jar will not work for here, since the IDE will not understand this. This means all libraries have to be installed properly. However, I dont want to have everyone installing it using "mvn install-file".
In my project I needed metawidget. Here we go:
Create a new maven project (name it "shared-libs" or something like that).
Download metawidget and extract the zip into src/main/lib.
The folder doc/api contains the javadocs. Create a zip of the content (doc/api/api.zip).
Modify the pom like this
Build the project and the library will be installed.
Add the library as a dependency to your project, or (if you added the dependency in the shared-libs project) add shared-libs as dependency to get all libraries at once.
Every time you have a new library, just add a new execution and tell everyone to build the project again (you can improve this process with project hierachies).
For those that didn't find a good answer here, this is what we are doing to get a jar with all the necessary dependencies in it. This answer (https://stackoverflow.com/a/7623805/1084306) mentions to use the Maven Assembly plugin but doesn't actually give an example in the answer. And if you don't read all the way to the end of the answer (it's pretty lengthy), you may miss it. Adding the below to your pom.xml will generate target/${PROJECT_NAME}-${VERSION}-jar-with-dependencies.jar
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.4.1</version>
<configuration>
<!-- get all project dependencies -->
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<!-- MainClass in mainfest make a executable jar -->
<archive>
<manifest>
<mainClass>my.package.mainclass</mainClass>
</manifest>
</archive>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<!-- bind to the packaging phase -->
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
I alluded to some python code in a comment to the answer from #alex lehmann's , so am posting it here.
def AddJars(jarList):
s1 = ''
for elem in jarList:
s1+= """
<dependency>
<groupId>local.dummy</groupId>
<artifactId>%s</artifactId>
<version>0.0.1</version>
<scope>system</scope>
<systemPath>${project.basedir}/manual_jars/%s</systemPath>
</dependency>\n"""%(elem, elem)
return s1
This doesn't answer how to add them to your POM, and may be a no brainer, but would just adding the lib dir to your classpath work? I know that is what I do when I need an external jar that I don't want to add to my Maven repos.
Hope this helps.
What works in our project is what Archimedes Trajano wrote, but we had in our .m2/settings.xml something like this:
<mirror>
<id>nexus</id>
<mirrorOf>*</mirrorOf>
<url>http://url_to_our_repository</url>
</mirror>
and the * should be changed to central. So if his answer doesn't work for you, you should check your settings.xml
I just wanted a quick and dirty workaround... I couldn't run the script from Nikita Volkov: syntax error + it requires a strict format for the jar names.
I made this Perl script which works with whatever format for the jar file names, and it generates the dependencies in an xml so it can be copy pasted directly in a pom.
If you want to use it, make sure you understand what the script is doing, you may need to change the lib folder and the value for the groupId or artifactId...
#!/usr/bin/perl
use strict;
use warnings;
open(my $fh, '>', 'dependencies.xml') or die "Could not open file 'dependencies.xml' $!";
foreach my $file (glob("lib/*.jar")) {
print "$file\n";
my $groupId = "my.mess";
my $artifactId = "";
my $version = "0.1-SNAPSHOT";
if ($file =~ /\/([^\/]*?)(-([0-9v\._]*))?\.jar$/) {
$artifactId = $1;
if (defined($3)) {
$version = $3;
}
`mvn install:install-file -Dfile=$file -DgroupId=$groupId -DartifactId=$artifactId -Dversion=$version -Dpackaging=jar`;
print $fh "<dependency>\n\t<groupId>$groupId</groupId>\n\t<artifactId>$artifactId</artifactId>\n\t<version>$version</version>\n</dependency>\n";
print " => $groupId:$artifactId:$version\n";
} else {
print "##### BEUH...\n";
}
}
close $fh;
The solution for scope='system' approach in Java:
public static void main(String[] args) {
String filepath = "/Users/Downloads/lib/";
try (Stream<Path> walk = Files.walk(Paths.get(filepath))) {
List<String> result = walk.filter(Files::isRegularFile)
.map(x -> x.toString()).collect(Collectors.toList());
String indentation = " ";
for (String s : result) {
System.out.println(indentation + indentation + "<dependency>");
System.out.println(indentation + indentation + indentation + "<groupId>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</groupId>");
System.out.println(indentation + indentation + indentation + "<artifactId>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</artifactId>");
System.out.println(indentation + indentation + indentation + "<version>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</version>");
System.out.println(indentation + indentation + indentation + "<scope>system</scope>");
System.out.println(indentation + indentation + indentation + "<systemPath>" + s + "</systemPath>");
System.out.println(indentation + indentation + "</dependency>");
}
} catch (IOException e) {
e.printStackTrace();
}
}

Maven , How to let dependency of local system jar be included into the output jar? [duplicate]

Maven 2 is driving me crazy during the experimentation / quick and dirty mock-up phase of development.
I have a pom.xml file that defines the dependencies for the web-app framework I want to use, and I can quickly generate starter projects from that file. However, sometimes I want to link to a 3rd party library that doesn't already have a pom.xml file defined, so rather than create the pom.xml file for the 3rd party lib by hand and install it, and add the dependency to my pom.xml, I would just like to tell Maven: "In addition to my defined dependencies, include any jars that are in /lib too."
It seems like this ought to be simple, but if it is, I am missing something.
Any pointers on how to do this are greatly appreciated. Short of that, if there is a simple way to point maven to a /lib directory and easily create a pom.xml with all the enclosed jars mapped to a single dependency which I could then name / install and link to in one fell swoop would also suffice.
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 Repo" 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 jars 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:
<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 dir 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 repo
Instead of creating this structure by hand I recommend to use a Maven plugin to install your jars 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 pom to:
<repository>
<id>repo</id>
<url>file://${project.basedir}/repo</url>
</repository>
A helper script
Since executing installation command for each lib is kinda annoying and definitely error prone, I've created a utility script which automatically installs all the jars from a lib folder to a project repository, while automatically resolving all metadata (groupId, artifactId and etc.) from names of files. The script also prints out the dependencies xml for you to copy-paste in your pom.
Include the dependencies in your target package
When you'll have your in-project repository created you'll have solved a problem of distributing the dependencies of the project with its source, but since then your project's target artifact will depend on non-published jars, so when you'll install it to a repository it will have unresolvable dependencies.
To beat this problem I suggest to include these dependencies in your target package. This you can do with either the Assembly Plugin or better with the OneJar Plugin. The official documentaion on OneJar is easy to grasp.
For throw away code only
set scope == system and just make up a groupId, artifactId, and version
<dependency>
<groupId>org.swinglabs</groupId>
<artifactId>swingx</artifactId>
<version>0.9.2</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/swingx-0.9.3.jar</systemPath>
</dependency>
Note: system dependencies are not copied into resulted jar/war
(see How to include system dependencies in war built using maven)
You may create local repository on your project
For example if you have libs folder in project structure
In libs folder you should create directory structure like: /groupId/artifactId/version/artifactId-version.jar
In your pom.xml you should register repository
<repository>
<id>ProjectRepo</id>
<name>ProjectRepo</name>
<url>file://${project.basedir}/libs</url>
</repository>
and add dependency as usual
<dependency>
<groupId>groupId</groupId>
<artifactId>artifactId</artifactId>
<version>version</version>
</dependency>
That is all.
For detailed information: How to add external libraries in Maven (archived)
Note: When using the System scope (as mentioned on this page), Maven needs absolute paths.
If your jars are under your project's root, you'll want to prefix your systemPath values with ${basedir}.
This is what I have done, it also works around the package issue and it works with checked out code.
I created a new folder in the project in my case I used repo, but feel free to use src/repo
In my POM I had a dependency that is not in any public maven repositories
<dependency>
<groupId>com.dovetail</groupId>
<artifactId>zoslog4j</artifactId>
<version>1.0.1</version>
<scope>runtime</scope>
</dependency>
I then created the following directories repo/com/dovetail/zoslog4j/1.0.1 and copied the JAR file into that folder.
I created the following POM file to represent the downloaded file (this step is optional, but it removes a WARNING) and helps the next guy figure out where I got the file to begin with.
<?xml version="1.0" encoding="UTF-8" ?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.dovetail</groupId>
<artifactId>zoslog4j</artifactId>
<packaging>jar</packaging>
<version>1.0.1</version>
<name>z/OS Log4J Appenders</name>
<url>http://dovetail.com/downloads/misc/index.html</url>
<description>Apache Log4j Appender for z/OS Logstreams, files, etc.</description>
</project>
Two optional files I create are the SHA1 checksums for the POM and the JAR to remove the missing checksum warnings.
shasum -b < repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.jar \
> repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.jar.sha1
shasum -b < repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.pom \
> repo/com/dovetail/zoslog4j/1.0.1/zoslog4j-1.0.1.pom.sha1
Finally I add the following fragment to my pom.xml that allows me to refer to the local repository
<repositories>
<repository>
<id>project</id>
<url>file:///${basedir}/repo</url>
</repository>
</repositories>
This is how we add or install a local jar
<dependency>
<groupId>org.example</groupId>
<artifactId>iamajar</artifactId>
<version>1.0</version>
<scope>system</scope>
<systemPath>${project.basedir}/lib/iamajar.jar</systemPath>
</dependency>
i gave some default groupId and artifactId because they are mandatory :)
You really ought to get a framework in place via a repository and identifying your dependencies up front. Using the system scope is a common mistake people use, because they "don't care about the dependency management." The trouble is that doing this you end up with a perverted maven build that will not show maven in a normal condition. You would be better off following an approach like this.
Maven install plugin has command line usage to install a jar into the local repository, POM is optional but you will have to specify the GroupId, ArtifactId, Version and Packaging (all the POM stuff).
Using <scope>system</scope> is a terrible idea for reasons explained by others, installing the file manually to your local repository makes the build unreproducible, and using <url>file://${project.basedir}/repo</url> is not a good idea either because (1) that may not be a well-formed file URL (e.g. if the project is checked out in a directory with unusual characters), (2) the result is unusable if this project’s POM is used as a dependency of someone else’s project.
Assuming you are unwilling to upload the artifact to a public repository, Simeon’s suggestion of a helper module does the job. But there is an easier way now…
The Recommendation
Use non-maven-jar-maven-plugin. Does exactly what you were asking for, with none of the drawbacks of the other approaches.
I found another way to do this, see here from a Heroku post
To summarize (sorry about some copy & paste)
Create a repo directory under your root folder:
yourproject
+- pom.xml
+- src
+- repo
Run this to install the jar to your local repo directory
mvn deploy:deploy-file -Durl=file:///path/to/yourproject/repo/ -Dfile=mylib-1.0.jar -DgroupId=com.example -DartifactId=mylib -Dpackaging=jar -Dversion=1.0
Add this your pom.xml:
<repositories>
<!--other repositories if any-->
<repository>
<id>project.local</id>
<name>project</name>
<url>file:${project.basedir}/repo</url>
</repository>
</repositories>
<dependency>
<groupId>com.example</groupId>
<artifactId>mylib</artifactId>
<version>1.0</version>
</dependency>
What seems simplest to me is just configure your maven-compiler-plugin to include your custom jars. This example will load any jar files in a lib directory.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<includes>
<include>lib/*.jar</include>
</includes>
</configuration>
</plugin>
After having really long discussion with CloudBees guys about properly maven packaging of such kind of JARs, they made an interesting good proposal for a solution:
Creation of a fake Maven project which attaches a pre-existing JAR as a primary artifact, running into belonged POM install:install-file execution. Here is an example of such kinf of POM:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-install-plugin</artifactId>
<version>2.3.1</version>
<executions>
<execution>
<id>image-util-id</id>
<phase>install</phase>
<goals>
<goal>install-file</goal>
</goals>
<configuration>
<file>${basedir}/file-you-want-to-include.jar</file>
<groupId>${project.groupId}</groupId>
<artifactId>${project.artifactId}</artifactId>
<version>${project.version}</version>
<packaging>jar</packaging>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
But in order to implement it, existing project structure should be changed. First, you should have in mind that for each such kind of JAR there should be created different fake Maven project (module). And there should be created a parent Maven project including all sub-modules which are : all JAR wrappers and existing main project. The structure could be :
root project (this contains the parent POM file includes all sub-modules with module XML element) (POM packaging)
JAR 1 wrapper Maven child project (POM packaging)
JAR 2 wrapper Maven child project (POM packaging)
main existing Maven child project (WAR, JAR, EAR .... packaging)
When parent running via mvn:install or mvn:packaging is forced and sub-modules will be executed. That could be concerned as a minus here, since project structure should be changed, but offers a non static solution at the end
The problem with systemPath is that the dependencies' jars won't get distributed along your artifacts as transitive dependencies. Try what I've posted here: Is it best to Mavenize your project jar files or put them in WEB-INF/lib?
Then declare dependencies as usual.
And please read the footer note.
If you want a quick and dirty solution, you can do the following (though I do not recommend this for anything except test projects, maven will complain in length that this is not proper).
Add a dependency entry for each jar file you need, preferably with a perl script or something similar and copy/paste that into your pom file.
#! /usr/bin/perl
foreach my $n (#ARGV) {
$n=~s#.*/##;
print "<dependency>
<groupId>local.dummy</groupId>
<artifactId>$n</artifactId>
<version>0.0.1</version>
<scope>system</scope>
<systemPath>\${project.basedir}/lib/$n</systemPath>
</dependency>
";
A quick&dirty batch solution (based on Alex's answer):
libs.bat
#ECHO OFF
FOR %%I IN (*.jar) DO (
echo ^<dependency^>
echo ^<groupId^>local.dummy^</groupId^>
echo ^<artifactId^>%%I^</artifactId^>
echo ^<version^>0.0.1^</version^>
echo ^<scope^>system^</scope^>
echo ^<systemPath^>${project.basedir}/lib/%%I^</systemPath^>
echo ^</dependency^>
)
Execute it like this: libs.bat > libs.txt.
Then open libs.txt and copy its content as dependencies.
In my case, I only needed the libraries to compile my code, and this solution was the best for that purpose.
To install the 3rd party jar which is not in maven repository use maven-install-plugin.
Below are steps:
Download the jar file manually from the source (website)
Create a folder and place your jar file in it
Run the below command to install the 3rd party jar in your local maven repository
mvn install:install-file -Dfile= -DgroupId=
-DartifactId= -Dversion= -Dpackaging=
Below is the e.g one I used it for simonsite log4j
mvn install:install-file
-Dfile=/Users/athanka/git/MyProject/repo/log4j-rolling-appender.jar -DgroupId=uk.org.simonsite -DartifactId=log4j-rolling-appender -Dversion=20150607-2059 -Dpackaging=jar
In the pom.xml include the dependency as below
<dependency>
<groupId>uk.org.simonsite</groupId>
<artifactId>log4j-rolling-appender</artifactId>
<version>20150607-2059</version>
</dependency>
Run the mvn clean install command to create your packaging
Below is the reference link:
https://maven.apache.org/guides/mini/guide-3rd-party-jars-local.html
A strange solution I found:
using Eclipse
create simple (non-maven) java project
add a Main class
add all the jars to the classpath
export Runnable JAR (it's important, because no other way here to do it)
select Extract required libraries into generated JAR
decide the licence issues
tadammm...install the generated jar to your m2repo
add this single dependency to your other projects.
cheers,
Balint
Even though it does not exactly fit to your problem, I'll drop this here. My requirements were:
Jars that can not be found in an online maven repository should be in the SVN.
If one developer adds another library, the other developers should not be bothered with manually installing them.
The IDE (NetBeans in my case) should be able find the sources and javadocs to provide autocompletion and help.
Let's talk about (3) first: Just having the jars in a folder and somehow merging them into the final jar will not work for here, since the IDE will not understand this. This means all libraries have to be installed properly. However, I dont want to have everyone installing it using "mvn install-file".
In my project I needed metawidget. Here we go:
Create a new maven project (name it "shared-libs" or something like that).
Download metawidget and extract the zip into src/main/lib.
The folder doc/api contains the javadocs. Create a zip of the content (doc/api/api.zip).
Modify the pom like this
Build the project and the library will be installed.
Add the library as a dependency to your project, or (if you added the dependency in the shared-libs project) add shared-libs as dependency to get all libraries at once.
Every time you have a new library, just add a new execution and tell everyone to build the project again (you can improve this process with project hierachies).
For those that didn't find a good answer here, this is what we are doing to get a jar with all the necessary dependencies in it. This answer (https://stackoverflow.com/a/7623805/1084306) mentions to use the Maven Assembly plugin but doesn't actually give an example in the answer. And if you don't read all the way to the end of the answer (it's pretty lengthy), you may miss it. Adding the below to your pom.xml will generate target/${PROJECT_NAME}-${VERSION}-jar-with-dependencies.jar
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.4.1</version>
<configuration>
<!-- get all project dependencies -->
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<!-- MainClass in mainfest make a executable jar -->
<archive>
<manifest>
<mainClass>my.package.mainclass</mainClass>
</manifest>
</archive>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<!-- bind to the packaging phase -->
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
I alluded to some python code in a comment to the answer from #alex lehmann's , so am posting it here.
def AddJars(jarList):
s1 = ''
for elem in jarList:
s1+= """
<dependency>
<groupId>local.dummy</groupId>
<artifactId>%s</artifactId>
<version>0.0.1</version>
<scope>system</scope>
<systemPath>${project.basedir}/manual_jars/%s</systemPath>
</dependency>\n"""%(elem, elem)
return s1
This doesn't answer how to add them to your POM, and may be a no brainer, but would just adding the lib dir to your classpath work? I know that is what I do when I need an external jar that I don't want to add to my Maven repos.
Hope this helps.
What works in our project is what Archimedes Trajano wrote, but we had in our .m2/settings.xml something like this:
<mirror>
<id>nexus</id>
<mirrorOf>*</mirrorOf>
<url>http://url_to_our_repository</url>
</mirror>
and the * should be changed to central. So if his answer doesn't work for you, you should check your settings.xml
I just wanted a quick and dirty workaround... I couldn't run the script from Nikita Volkov: syntax error + it requires a strict format for the jar names.
I made this Perl script which works with whatever format for the jar file names, and it generates the dependencies in an xml so it can be copy pasted directly in a pom.
If you want to use it, make sure you understand what the script is doing, you may need to change the lib folder and the value for the groupId or artifactId...
#!/usr/bin/perl
use strict;
use warnings;
open(my $fh, '>', 'dependencies.xml') or die "Could not open file 'dependencies.xml' $!";
foreach my $file (glob("lib/*.jar")) {
print "$file\n";
my $groupId = "my.mess";
my $artifactId = "";
my $version = "0.1-SNAPSHOT";
if ($file =~ /\/([^\/]*?)(-([0-9v\._]*))?\.jar$/) {
$artifactId = $1;
if (defined($3)) {
$version = $3;
}
`mvn install:install-file -Dfile=$file -DgroupId=$groupId -DartifactId=$artifactId -Dversion=$version -Dpackaging=jar`;
print $fh "<dependency>\n\t<groupId>$groupId</groupId>\n\t<artifactId>$artifactId</artifactId>\n\t<version>$version</version>\n</dependency>\n";
print " => $groupId:$artifactId:$version\n";
} else {
print "##### BEUH...\n";
}
}
close $fh;
The solution for scope='system' approach in Java:
public static void main(String[] args) {
String filepath = "/Users/Downloads/lib/";
try (Stream<Path> walk = Files.walk(Paths.get(filepath))) {
List<String> result = walk.filter(Files::isRegularFile)
.map(x -> x.toString()).collect(Collectors.toList());
String indentation = " ";
for (String s : result) {
System.out.println(indentation + indentation + "<dependency>");
System.out.println(indentation + indentation + indentation + "<groupId>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</groupId>");
System.out.println(indentation + indentation + indentation + "<artifactId>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</artifactId>");
System.out.println(indentation + indentation + indentation + "<version>"
+ s.replace(filepath, "").replace(".jar", "")
+ "</version>");
System.out.println(indentation + indentation + indentation + "<scope>system</scope>");
System.out.println(indentation + indentation + indentation + "<systemPath>" + s + "</systemPath>");
System.out.println(indentation + indentation + "</dependency>");
}
} catch (IOException e) {
e.printStackTrace();
}
}

importing external jar inside eclipse

I'm writing assignment on coursera.org Java course. I'm using Maven and I have external jars that I have to use in this course (course requirements).
This is part of my pom.xml:
<dependency>
<groupId>org.coursera.algs4part1</groupId>
<artifactId>stdlib</artifactId>
<version>1.0</version>
</dependency>
I can't make java compiler import the external jar file. Below, following errors occur:
The import org.coursera.algs4part1.stdlib cannot be resolved
But I've successfully added the jar to maven:
What am I missing?
You need to do the following steps if you have a eclipse-maven plugin installed.
Run the command mvn eclipse:eclipse
Go to Project Properties > Build Path > Libraries tab > Add Variable... button > Configure Variables... button > New button. Enter the variable name as M2_REPO and its value/path to the Maven Repository path (Usually it's like C:\Users\<username>\.m2\repository.)
1.create a folder src\lib and paste your jar file
2.your pom.xml should be like this.
<groupId>org.coursera.algs4part1</groupId>
<artifactId>stdlib</artifactId>
<scope>system</scope>
<version>1.0</version>
<systemPath>${basedir}\src\lib\stdlib.jar</systemPath>
</dependency>
Hopefully this will solve your problem and for more details visit http://noexceptionfound.blogspot.in/

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