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Occurred an error while packaging spring-boot application by maven

The IDEA app told me that Invalid packaging for parent POM org.springframework.boot:spring-boot-starter-web:1.5.9.RELEASE, must be "pom" but is "jar" while I packaged my easy-start spring-boot application, how to solve this problem?
My platform is macOS 10.15.7 with 3 JDKs(1.8, 11, 14), and I am using maven-3.6.3, my maven settings are also changed the JDK to 1.8 and 11
The pom.xml file is as followed:
<?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>org.example</groupId>
<artifactId>SpringBoot-01-HelloWorld</artifactId>
<version>1.0</version>
<packaging>pom</packaging>
<parent>
<artifactId>spring-boot-starter-web</artifactId>
<groupId>org.springframework.boot</groupId>
<version>1.5.9.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>

The parent POM should be the Spring Boot parent project
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.9.RELEASE</version>
</parent>

Creating multi module project using Intellij & Maven

I have a project structure which has a core tool and a REST API to interact and configure that tool.
I have a package structure like this:
com.example.api -> contains API definitions
com.example.commons -> contains module common to both core and api
com.exmaple.core -> contains the core module
This is primarily a Spring Boot application and both will run in different containers. So the API and the Core jar will be different.
How do I create a multi-module project with this structure so that I can also use the commons module in both the sub packages(core & api).
Suggestions on how to configure Maven and IntelliJ in such an environment?
Is my pattern right? Are there other well known patterns for this kind of project structure?

You can have a multi Maven module project as you wish. Here's an example on how you should configure your modules:
Create a parent pom.xml as follows (note that I am not adding spring-boot-starter-parent as a parent to the project, I am bringing in the Spring Boot dependencies with spring-boot-dependencies):
<?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.example</groupId>
<artifactId>parent</artifactId>
<packaging>pom</packaging>
<version>1.0.0-SNAPSHOT</version>
<modules>
<module>example-commons</module>
<module>example-core</module>
<module>example-api</module>
</modules>
<dependencyManagement>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-dependencies -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>1.5.3.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>1.5.3.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-test -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>1.5.3.RELEASE</version>
</dependency>
</dependencies>
</project>
And a non executable module's pom.xml would be like:
<?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">
<parent>
<artifactId>parent</artifactId>
<groupId>com.example</groupId>
<version>1.0.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>example-commons</artifactId>
</project>
whereas an executable module's pom.xml would be like (note the spring-boot-maven-plugin is present only here for this dependency):
<?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">
<parent>
<artifactId>parent</artifactId>
<groupId>com.example</groupId>
<version>1.0.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>example-core</artifactId>
<build>
<plugins>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-maven-plugin -->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>1.5.3.RELEASE</version>
<configuration>
<executable>true</executable>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>example-commons</artifactId>
<version>1.0.0-SNAPSHOT</version>
</dependency>
</dependencies>
</project>

How to package a maven multi-module properly?

I'm building a multi-module rest service with Maven and Spring Boot that will be published on a WebLogic Server, and I'm a bit confuse about how to configure the packaging of the application modules.
My current structure is:
/application
/main (main mehtod for spring-boot)
/api
/service
/dao
The parent project (application folder) is set up as pom packaging, but child projects I'm not sure how to configure it. I believe the correct way would be packaging like .jar file, but i saw some examples on the internet of Java projects with Maven multi-modules defined as war.
can someone tell me what's the correct way to define the child modules packaging in this case?
My 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.radarveicular</groupId>
<artifactId>radarveicular-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.8</java.version>
<javax.inject.version>1</javax.inject.version>
</properties>
<modules>
<module>radarveicular-api</module>
<module>radarveicular-service</module>
<module>radarveicular-main</module>
<module>radarveicular-dao</module>
</modules>
<build>
<plugins>
<plugin>
<artifactId>maven-eclipse-plugin</artifactId>
<configuration>
<downloadSources>true</downloadSources>
<downloadJavadocs>true</downloadJavadocs>
<wtpversion>2.0</wtpversion>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
<encoding>${project.build.sourceEncoding}</encoding>
</configuration>
</plugin>
</plugins>
</build>
</project>
main pom:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>radarveicular-main</artifactId>
<dependencies>
<dependency>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-api</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<!-- Spring Framework -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
</dependency>
</dependencies>
<build>
<finalName>${project.artifactId}</finalName>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
api 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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>radarveicular-api</artifactId>
<dependencies>
<dependency>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-service</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
</project>
service 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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>radarveicular-service</artifactId>
<dependencies>
<dependency>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-dao</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
</dependencies>
</project>
dao 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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.radarveicular</groupId>
<artifactId>radarveicular-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>radarveicular-dao</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.30</version>
</dependency>
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.4</version>
</dependency>
</dependencies>
</project>

I think your problem is that your parent pom.xml shouldn't handle your spring boot project. Meaning, you should have this in it :
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
I recommend that your pom.xml parent only handles your modules and dependencies as pom packaging :
Packaging
<packaging>pom</packaging>
Modules
<modules>
<module>radarveicular-api</module>
<module>radarveicular-service</module>
<module>radarveicular-main</module>
<module>radarveicular-dao</module>
</modules>
Then, you will have your module radarveicular-main with the spring boot parent :
Parent
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
Packaging
<packaging>war</packaging>
I hope this will help you. =)

I feel your question is more towards designing part of multi module.
Multi module management of application can depend on various things.
One thing could be if you want to deploy each sub module as separate module/service based, which can be turned off/on based on need. In that case it would help you if you build each of module as separate war and deploy them separately.
If you have to deploy it as a single war than most straight forward would to create all dependent modules as jar and include them in parent project. In this way a single war will be deployed.
You can have a hybrid approach of above two.
Hopefully i have understood your question correctly. :)
Happy coding!!

How to build neo4j-jdbc driver from official repo?

I wanted to use the neo4j-jdbc (https://github.com/neo4j-contrib/neo4j-jdbc) to connect to my Neo4j 3.0 server. I'd like to build the driver myself so that I can add it to another project as a jar file. I'm struggling to understand the readme on the official repo.
Could someone please explain how to do this, I'm hoping to clone the repo and build in Eclipse. I understand how to clone the repo it's how you go about building the driver.
Many thanks,

As you said in the comments it seems that you want to simply connect to a Neo4j server, and as most people recommend you should use Maven or Gradle to work with your dependecies.
For that you're gonna need to create a new Maven Project:
and when you finish creating you're gonna have a project similar to this one, the one file you're looking to add this capability to connect to Neo4j is the pom.xml:
To be able to connect to Neo4j simply add this to the <dependencies></dependencies> tag:
<dependency>
<groupId>org.neo4j</groupId>
<artifactId>neo4j-jdbc</artifactId>
<version>3.0</version>
</dependency>
Here's an example of a pom.xml created automaticly by a Spring Starter Project:
<?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.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.6.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

Managing Spring Boot parent POM version in multiple projects

I've created a few Spring Boot projects, each one's POM including a spring-boot-starter-parent as a parent. Whenever a new version comes out, I currently need to manually update it in every POM.
Adding a POM dependency which already has the spring-boot-starter-parent does not help, and the Spring Boot documentation states that using an 'import' scope will only work for dependencies, and not the Spring Boot version itself.
Is there a way to define a "super-pom" which all my projects can inherit from, where I can set the Spring Boot version once, and not go through each project?

Here is an approach you can try.
Your 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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<!-- Do you really need to have this parent? -->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.2.7.RELEASE</version>
</parent>
<groupId>org.example</groupId>
<artifactId>my-parent</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>pom</packaging>
<name>Parent POM</name>
<properties>
<!-- Change this property to switch Spring Boot version-->
<spring.boot.version>1.2.7.RELEASE</spring.boot.version>
</properties>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>${spring.boot.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<!-- Declare the Spring Boot dependencies you need here
Please note that you don't need to declare the version tags.
That's the whole point of the import above.
-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-actuator</artifactId>
</dependency>
<!-- About 50 in total if you need them all -->
...
</dependencies>
</project>
A child 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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.example</groupId>
<artifactId>my-parent</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<artifactId>my-child</artifactId>
<name>Child POM</name>
</project>
If you do a mvn dependency:tree on the child POM, you'll see that they are all in there.