Try to run Maven import with -U flag (force update snapshots)

I use Intellij > new > project from version control and clone the repository from
https://github.com/eugenp/tutorials.git

then error:
Could not find artifact org.baeldung.pmd:custom-pmd:pom:0.0.1 in central (https://repo.maven.apache.org/maven2)
Could not find artifact org.baeldung.pmd:custom-pmd:jar:0.0.1 in central (https://repo.maven.apache.org/maven2)

Cannot resolve plugin org.apache.maven.plugins:maven-pmd-plugin:3.19.0

Try to run Maven import with -U flag (force update snapshots)

what is the problem and what should I do now?

image as follow:

Ok, I press the reload all maven projects icon and no error is shown now.

I don't think that there are any org.baeldung artefacts in the world-wide Maven Repository.

What it looks like is that you have a multi-project projects where one project/POM depends on another project/POM. So you need to go back to baeldung and check the instructions more carefully. They're usually good with their documentation.

Please avoid posting screenshots where possible. Text copy/paste is better. It saves server space and is more readable.

I try to find any documentations for running their sources in github but cannot find it, maybe need take its paid course to know.

I looked at that project. It's not from Baeldung, which explains why it's not self-contained. It's also not a "project" as such, but rather a set of different sub-projects collected together to make a downloadable whole. The sub-projects each have README files that link to an article and can be built and tested individually. For example:
cd spring-quartz mvn clean install

The top (root)-level POM can build the sub-projects in bulk, but you do have to follow the instructions in the README, since this multi-project project has some stuff that requires Java 8 and some that requires Java 9 and later and since there was a major break in how Java handles introspection between the two versions, they're handled differently.

Tim Holloway wrote:I looked at that project. It's not from Baeldung, which explains why it's not self-contained. It's also not a "project" as such, but rather a set of different sub-projects collected together to make a downloadable whole. The sub-projects each have README files that link to an article and can be built and tested individually. For example:
cd spring-quartz mvn clean install

The top (root)-level POM can build the sub-projects in bulk, but you do have to follow the instructions in the README, since this multi-project project has some stuff that requires Java 8 and some that requires Java 9 and later and since there was a major break in how Java handles introspection between the two versions, they're handled differently.

Yes, the sub-projects I try to run is
spring-data-jpa-repo, the relevant articles is
Spring Data – CrudRepository save() Method
it has three pom.xml (one pom, and inherit two from parents),
tutorials\persistence-modules\spring-data-jap-repo\pom.xml
tutorials\parent-boot-2\pom.xml
tutorials\pom.xml

I add
<properties>        <start-class>com.baeldung.Application</start-class>    </properties>
in tutorials\persistence-modules\spring-data-jap-repo\pom.xml,
then run
{path} \tutorials\persistence-modules\spring-data-jpa-repo> mvn spring-boot:run
but it returns many error like
2023-01-26 00:54:56.029  INFO 12620 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JDBC repositories in DEFAULT mode.
2023-01-26 00:54:56.032  INFO 12620 --- [           main] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candid
ate interface com.baeldung.derivedquery.repository.UserRepository; If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations:
org.springframework.data.relational.core.mapping.Table.
..........\\ other error
2023-01-26 00:54:59.766  WARN 12620 --- [           main] o.h.t.s.i.ExceptionHandlerLoggedImpl     : GenerationTarget encountered exception accepting command : Error executing DDL "cre
ate table car (id bigint generated by default as identity, model varchar(255), year integer, primary key (id))" via JDBC Statement

org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "create table car (id bigint generated by default as identity, model varchar(255), year integer, primary k
ey (id))" via JDBC Statement
       at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:67) ~[hibernate-core-5.6.12.Final.jar:5.6.12.Final]
       at org.hibernate.tool.schema.internal.SchemaCreatorImpl.applySqlString(SchemaCreatorImpl.java:458) ~[hibernate-core-5.6.12.Final.jar:5.6.12.Final]
       at org.hibernate.tool.schema.internal.SchemaCreatorImpl.applySqlStrings(SchemaCreatorImpl.java:442) ~[hibernate-core-5.6.12.Final.jar:5.6.12.Final]

and the article
https://www.baeldung.com/spring-data-crud-repository-save
has not mentioned how to run the code, so don't know what to do.

Tim Holloway wrote:I don't think that there are any org.baeldung artefacts in the world-wide Maven Repository.

https://mvnrepository.com/artifact/org.baeldung.pmd/custom-pmd

I noticed an "ICM" above the single version. If I click on the version I see this:

Note: this artifact is located at ICM repository (http://maven.icm.edu.pl/artifactory/repo/)

So to access it, you need to add a <repositories> section, see https://maven.apache.org/guides/mini/guide-multiple-repositories.html for a bit more information.
(I currently get a 400 in the browser, so I don't know for sure if it actually works.)

Update: I tried a bit with mvn dependency:get, but after using Maven 3.6.3 (because 3.8.x blocks the http URL, and the site doesn't work properly with https) I get a 400 again. I guess that the Maven repository is broken.