使用Java Spring Boot，如何将依赖项，源代码和Spring合并到一个Jar文件中

Question

been wrestling with this issue for a few days and would appreciate some guidance.

I am working with Spring Boot and am attempting to build my project into a jar that I can run. There are some nested dependencies (OpenCV) that require me to include them all together into the one Jar file.

Before I added these dependencies, I was able to successfully build a Jar file that worked just fine; it wasn't until I started trying to build a combined jar that things started to become an issue.

The problem I am facing is this: How do I successfully build a Jar file that includes all of the Spring files, nested dependencies, and my source code all into one fat Jar file?

Here is my POM file below with a few of the dependencies omitted.

<?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.myapp</groupId>
    <artifactId>mytestproject</artifactId>
    <packaging>jar</packaging>
    <!--Change the above to a war instead of jar if you need a war file-->
    <name>Spring OSGi Bundle</name>
    <version>0.1</version>
    <url>http://www.springframework.org/osgi</url>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
    </parent>

    <properties>
        <spring.osgi.version>1.2.1</spring.osgi.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <java.version>1.8</java.version>
    </properties>

    <!-- ================================================ -->
    <!--            Repository Configuration              -->
    <!-- ================================================ -->

    <!-- Repos -->
    <repositories>

        <!-- Apache imaging https://commons.apache.org/proper/commons-imaging/index.html -->
        <repository>
            <id>apache.snapshots</id>
            <name>Apache Development Snapshot Repository</name>
            <url>https://repository.apache.org/content/repositories/snapshots/</url>
            <releases>
                <enabled>false</enabled>
            </releases>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>


        <repository>
            <id>jitpack.io</id>
            <url>https://jitpack.io</url>
        </repository>

        <repository>
            <id>i21-s3-osgi-repo</id>
            <name>i21 osgi artifacts repo</name>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
            <url>http://maven.springframework.org/osgi</url>
        </repository>


        <repository>
            <id>com.springsource.repository.bundles.external</id>
            <name>SpringSource Enterprise Bundle Repository - External Bundle Releases</name>
            <url>http://repository.springsource.com/maven/bundles/external</url>
        </repository>

        <repository>
            <id>com.springsource.repository.bundles.release</id>
            <name>SpringSource Enterprise Bundle Repository - SpringSource Bundle Releases</name>
            <url>http://repository.springsource.com/maven/bundles/release</url>
        </repository>

        <repository>
            <id>com.springsource.repository.bundles.milestone</id>
            <name>SpringSource Enterprise Bundle Repository - SpringSource Milestone Releases</name>
            <url>http://repository.springsource.com/maven/bundles/milestone</url>
        </repository>


        <repository>
            <id>spring-release</id>
            <name>Spring Portfolio Release Repository</name>
            <url>http://maven.springframework.org/release</url>
        </repository>

        <repository>
            <id>eclipse-repository</id>
            <name>Eclipse Repository</name>
            <url>http://repo1.maven.org/eclipse/</url>
        </repository>

        <repository>
            <id>spring-ext</id>
            <name>Spring External Dependencies Repository</name>
            <url>
                https://springframework.svn.sourceforge.net/svnroot/springframework/repos/repo-ext/
            </url>
        </repository>
    </repositories>

    <!-- Plugin Repos -->
    <pluginRepositories>
        <pluginRepository>
            <id>maven-repo</id>
            <name>maven repo</name>
            <url>http://repo1.maven.org/maven2/</url>
        </pluginRepository>
        <pluginRepository>
            <id>com.springsource.repository.bundles.milestone</id>
            <name>SpringSource Enterprise Bundle Repository - SpringSource Milestone Releases</name>
            <url>http://repository.springsource.com/maven/bundles/milestone</url>
        </pluginRepository>
    </pluginRepositories>

    <!-- Dependencies -->
    <dependencies>

        <!-- Local Jar File for open.cv -->
        <dependency>
            <groupId>org.openpnp</groupId>
            <artifactId>opencv</artifactId>
            <scope>system</scope>
            <version>3.2.0</version>
            <systemPath>${basedir}/src/main/libs/opencv-320.jar</systemPath>
        </dependency>

        <!-- OSGI -->
        <dependency>
            <groupId>org.springframework.osgi</groupId>
            <artifactId>spring-osgi-test</artifactId>
            <version>${spring.osgi.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.osgi</groupId>
            <artifactId>spring-osgi-annotation</artifactId>
            <version>${spring.osgi.version}</version>
            <scope>test</scope>
        </dependency>




    </dependencies>

    <!-- Build Tag -->
    <build>
        <sourceDirectory>${basedir}/src/main/java</sourceDirectory>
        <resources>
            <!-- standard Maven folder -->
            <resource>
                <directory>src/main/resources</directory>
            </resource>
            <!-- plus root folder -->
            <resource>
                <directory>.</directory>
                <includes>
                    <include>plugin.xml</include>
                    <include>META-INF/*</include>
                </includes>
            </resource>
        </resources>


        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <!--<classifier>sources</classifier>-->
                    <!--<classifier>spring-boot</classifier>-->
                    <mainClass>com.myapp.internal.MainLauncher</mainClass>
                    <addResources>true</addResources>
                    <!--<executable>true</executable>-->
                </configuration>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <!--<phase>compile</phase>-->
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <!--<classpath>.</classpath>-->
                            <addClasspath>true</addClasspath>
                            <mainClass>com.myapp.internal.MainLauncher</mainClass>
                        </manifest>
                    </archive>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <!--<execution>-->
                        <!--<id>attach-sources</id>-->
                        <!--<phase>compile</phase>-->
                        <!--<goals>-->
                            <!--<goal>single</goal>-->
                        <!--</goals>-->
                    <!--</execution>-->
                    <execution>
                        <id>assemble-all</id>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

There are 3 different commands I am trying to compile with at the terminal in the Intellij IDE:

1) mvn clean package

2) mvn clean install

3) mvn clean compile assembly:single

Those 3 commands coupled with changing the commented code within the build tag always yields one of two results:

Either I get one large jar file which has everything in it except my source code is not in the base directory (it is located under the BOOT-INF directory and can't be found when ran) and I get the standard "Could not find MainLauncher" error whenever I run it using java -jar {MyJar}.jar.

or

I get 2 jar files where the "jar-with-dependencies" version has my source code as well as the other libs, but has none of the Spring libs in it.

Consequently, neither of these 2 jars work as I need some combination of both of them.

Things I have tried thus far:

1) Packaging spring sub-projects into one jar

2) No source jar attached with maven-assembly-plugin

3) Include spring xml in jar by maven-assembly-plugin packaging

4) How do I create an an executable jar in Spring Boot?

5) https://www.mkyong.com/maven/create-a-fat-jar-file-maven-assembly-plugin/

What am I missing in order to accomplish the goal of one jar file with my source, spring files, and nested dependencies?

Answer 1

Ok, took quite a bit of research, but the short answer is, you cannot do what I had hoped you could with certain external libraries.

The longer explanation is this:

First, as per this answer , you need to remove the secondary gradle assembly dependency to have your POM file look like this:

<plugins>
    <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        <configuration>
            <mainClass>com.myapp.internal.MainLauncher</mainClass>
            <addResources>true</addResources>
        </configuration>
        <executions>
            <execution>
                <goals>
                    <goal>repackage</goal>
                </goals>
            </execution>
        </executions>
    </plugin>
</plugins>

Then make the build with this command:

mvn clean install

Second, as per this sample , you need to have the library (in my case, OpenCV ) and the respective files located along your path / classpath. Here's the link on how to do that with Java.

Once those steps are complete, you can run your jar with the standard

java -jar YOUR_JAR_HERE.jar

and it should work correctly.