构建Maven Java项目时如何包含其他Java项目

Question

I have two projects, Java Project and Maven Java Project . I build my Maven Java Project as runnable jar file using this pom setting.

<build>
    <plugins>
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <configuration>
                <finalName>ISO8583PostpaidServer</finalName>
                <!-- <finalName>ISO8583PrepaidServer</finalName> -->
                <archive>
                    <manifest>
                        <!-- If you want to compile as Prepaid change this class reference -->
                        <mainClass>PostpaidServer</mainClass>
                        <!-- <mainClass>PrepaidServer</mainClass> -->
                    </manifest>
                </archive>

                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>

                <appendAssemblyId>false</appendAssemblyId>
            </configuration>
        </plugin>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>

    </plugins>
  </build>

But i get an error because in my Build Path i add dependency to my Java Project . How to add standard Java Project as dependency to my Maven Project?

Thank you anyway :)

Answer 1

As you state, your problem is that you depend on a Java Project that is not managed with maven.

I think you have two options:

• Convert that project to a maven project, and create a multimodule Maven project. This is convenient if you are the owner of the other project.
• Build that project, take jar and create your own local maven repo. This is convenient in case you can't manage the other project, or you just want to use as a dependency.

1. CONVERT TO MAVEN AND CREATE MULTIMODULE

If you have the project source, and you can change it because it is on your own, the best choice is:

• Transform to a maven project
• Create a parent maven project with two modules: your project and your transformed project.
• Add dependency.

Transform to a maven project

It is not difficult to transform a Java Standard project to a maven project:

• Change source and resources paths to src/main/java/ and src/main/resources/ .
• Declare dependencies.
• Configure plugins.

If you are the owner, and controls that project, you can transform it in a few minutes. If you don't have control on the project, it could a tedious task.

Create a parent project

Once you get transformed your dependent project, create a new project structure as follows:

parent
 ├── module1
 │   ├── src ...
 │   └── pom.xml
 ├── module1
 │   ├── src ...
 │   └── pom.xml
 └── pom.xml

your parent pom.xml will declare a modules section to include both modules, and your modules pom.xml will include a parent section to reference parent project.

Parent pom

<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/maven-v4_0_0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>GROUP</groupId>
    <artifactId>PARENT</artifactId>
    <packaging>pom</packaging>
    <version>VERSION</version>

    ...

    <modules>
        <module>module1</module>
        <module>module2</module>
    </modules>

    ...

Modules pom

<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/maven-v4_0_0.xsd">

    <parent>
        <groupId>GROUP</groupId>
        <artifactId>PARENT</artifactId>
        <version>VERSION</version>
    </parent>

    <modelVersion>4.0.0</modelVersion>

    <artifactId>MODULE1</artifactId>
    <packaging>jar</packaging>

Declare dependency

Finally declare the dependency to module2 on module1

<dependency>
    <groupId>GROUP</groupId>
    <artifactId>MODULE2</artifactId>
    <version>VERSION</version>
</dependency>

2. OWN LOCAL MAVEN REPO OPTION

In this case, the most interesting option is to deploy your dependent jar on a private/corporate Nexus or Artifactory.

But, If you don't have access to a private/corporate repository, you can use a local maven repository in your project. This way has an advantage, because all programmers gets all dependencies resolved with no command.

Create your local repository

First, you have to create a folder to store local maven repository. I will do it in the root path of your repository, for example call it local-libs .

Then, when you want to add a private jar, run the following command:

mvn org.apache.maven.plugins:maven-install-plugin:2.3.1:install-file \
    -Dfile=YOU_FILE.jar \
    -DgroupId=GROUP \
    -DartifactId=ARTIFACT \
    -Dversion=VERSION \
    -Dpackaging=jar \
    -DlocalRepositoryPath=local-libs

This command will store your jar into your local maven repository ( and not in your HOME/.m2/repository ) as GROUP.ARTIFACT.VERSION .

Declare local maven repo on your projects pom

After you created your local maven repo, declare it in your pom.xml as follows:

<repositories>
    <repository>
        <id>local-repo</id>
        <name>Local Repo</name>
        <url>file://${project.basedir}/local-libs</url>
    </repository>
</repositories>

Declare dependency

Once you have created and declared your local maven repo, use it. Create a dependency as follows:

<dependency>
    <groupId>GROUP</groupId>
    <artifactId>ARTIFACT</artifactId>
    <version>VERSION</version>
</dependency>

And you don't have to do anything else.

Once you created your local maven repo, every programmer that gets your repo can work immediately, it is not needed to run again any mvn command.

Answer 2

The easiest method with Eclipse is:

1. Convert the Java projects to Maven project, Configure->Convert to Maven Project . Fill in Group Id , Artifact Id and version .

2. Run As->Maven install

3. In your project which wants to use them, add the above created dependency information in pom.xml