Maven - 为java项目中的每个java包创建一个jar

Question

lets say i have 3 packages and a jar needs to be created for every package containing only the contents in the current package. My attempt is:

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.4</version>
                <executions>
                    <execution>
                        <id>first-jar</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                        <configuration>
                            <classifier>first-jar</classifier>
                            <excludes>
                                <exclude>/maven.task.3/src/main/java/third/ThirdMain.java
                                </exclude>
                                <exclude>/maven.task.3/src/main/java/second/SecondMain.java
                                </exclude>
                            </excludes>
                        </configuration>
                    </execution>
                    <execution>
                        <id>second-jar</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                        <configuration>
                            <classifier>second-jar</classifier>
                            <excludes>
                                <exclude>/maven.task.3/src/main/java/first/FirstMain.java
                                </exclude>
                                <exclude>/maven.task.3/src/main/java/third/ThirdMain.java
                                </exclude>
                            </excludes>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

And this does indeed create different jars, however the content inside is the same, meaning the exclude clauses don't work. I tried excluding only the class(relative/absolute path) and only the package. Don't ask why i do this its for homework, it does not make a lot of sense! This is the way i attempt of doing it, if there is any other more efficient way please feel free to share it with me!

EDIT: Modular structure must not be used, it must be one single project.

Thanks in advance

Answer 1

It's already been answered in the comments but here's an example.

A parent pom:

<?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.essexboy</groupId>
  <artifactId>parent</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>pom</packaging>

  <modules>
    <module>jar1</module>
    <module>jar2</module>
  </modules>

</project>

And 2 child/modules poms, only the artifactId is different:

<?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>

  <parent>
    <artifactId>parent</artifactId>
    <groupId>com.essexboy</groupId>
    <version>1.0-SNAPSHOT</version>
  </parent>

  <artifactId>jar1</artifactId>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <build>
  </build>
</project>

Extra info

I created the parent with the command:

mvn archetype:generate -DarchetypeGroupId=org.codehaus.mojo.archetypes -DarchetypeArtifactId=pom-root -DarchetypeVersion=RELEASE

Then created 2 modules with the command

mvn archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=RELEASE

If you must have a single jar project (no modules and parent) you can do it with the shade-plugin :

<?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.essexboy</groupId>
    <artifactId>double-jar</artifactId>
    <version>1.0-SNAPSHOT</version>

    <name>double-jar</name>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.2.1</version>
                <executions>
                    <execution>
                        <id>1</id>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <finalName>jar1</finalName>
                            <filters>
                                <filter>
                                    <artifact>*:*</artifact>
                                    <excludes>
                                        <exclude>com/essexboy/App2*</exclude>
                                    </excludes>
                                </filter>
                            </filters>
                        </configuration>
                    </execution>
                    <execution>
                        <id>2</id>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <finalName>jar2</finalName>
                            <filters>
                                <filter>
                                    <artifact>*:*</artifact>
                                    <excludes>
                                        <exclude>com/essexboy/App1*</exclude>
                                    </excludes>
                                </filter>
                            </filters>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

Answer 2

I have accepted the above answer as right since it's the correct way to do it, but if some crazy kid like me tries to do it the wrong way, here's how:

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.4</version>
                <executions>
                    <execution>
                        <id>first-jar</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                        <configuration>
                            <classifier>first-jar</classifier>
                            <includes>
                                <include>first/FirstMain.class</include>
                                <include>log4j.properties</include>
                                <include>pictures/12px-Commons-logo.svg.png</include>
                                <include>textFiles/first.txt</include>
                            </includes>
                        </configuration>
                    </execution>
    </plugin>

Notice to use class instead of java, since it uses the compiled extention! As for the other files, they are resources on the classpath