[FIXED] Run Java Maven program from Linux terminal: ClassNotFoundException

Issue

I have Java maven project that read Json file and get some data. But I can not run my program by Linux Terminal.

package name: my

classname: StartProgram

OS Ubuntu 20.04.2.064

Maven 3.6.3

Java 14.0.2

I did next steps:

mvn clean install
cd target
java -cp jsonReader-0.0.1-SNAPSHOT.jar my.StartProgram

the output:

Error: Could not find or load main class my.StartProgram
Caused by: java.lang.ClassNotFoundException: my.StartProgram

Part of my pom.xml:

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <mainClass>my.StartProgram</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>

How I can fix it? Thank you in advance.

Solution

Simply way in project directory:

mvn exec:java -Dexec.mainClass="StartProgram"

Another way:

Your project depends on another external library, so when you use java -cp ... you mast provide all of them.

you can build dependency list by (need run once once when your pom chanegs):

mvn dependency:build-classpath -Dmdep.outputFile=cp.txt

and then you can run your program by:

java -cp `cat cp.txt`:target/jsonReader-1.0-SNAPSHOT.jar StartProgram

Answered By - Slawomir Jaranowski
Answer Checked By - Marilyn (JavaFixing Volunteer)