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How to make the Maven child project to have different version than the parent?

I am very new to Maven, and I am creating a Maven parent and child project. I want the child project to have a different version than the parent, but if I change the version, then I am getting the error Cannot resolve for some of the dependencies.
How can I have a have a parent version different than the child version?
Following are the current properties I have, which are working pretty fine:
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>io.parent-test</groupId>
<artifactId>io.parent-test</artifactId>
<version>0.9.1-SNAPSHOT</version>
<relativePath></relativePath>
</parent>
<artifactId>test-project-converter</artifactId>
<name>test-project</name>
<description>Test Project</description>
If I change the properties to include the different version for child then I get the error:
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>io.parent-test</groupId>
<artifactId>io.parent-test</artifactId>
<version>0.9.1-SNAPSHOT</version>
<relativePath></relativePath>
</parent>
<version>0.9.2-SNAPSHOT</version>
<artifactId>test-project-converter</artifactId>
<name>test-project</name>
<description>Test Project</description>
I have the following dependencies based on the version that is throwing the error:
<dependency>
<groupId>io.parent-dep</groupId>
<artifactId>parent-dev</artifactId>
<version>${project.version}</version>
</dependency>
I tried to look into some of the responses online and made modifications to my parent project to include the properties:
<properties>
<revision>0.9.2-SNAPSHOT</revision>
</properties>
and accordingly, change the child project to include the version <version>${revision}</version> but it's not working as expected.
Can someone please let me know how can I create a different snapshot version for my child project while keeping the parent project same?

I think because you are building wrong order of child and parent project. When you change the version of child project, you should first re-build child project with new version -> new jar file name (with old parent jar file if in the child project have parent dependency) then update the version of child dependency in the pom file of parent project and re-build parent project, then re-build child project again with the new parent jar file (the same version but include different child jar file).

I was able to fix it by providing the parent version ${project.parent.version} to the dependencies coming from the parent.
I tried this, and everything worked fine.
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>io.parent-test</groupId>
<artifactId>io.parent-test</artifactId>
<version>0.9.1-SNAPSHOT</version>
<relativePath></relativePath>
</parent>
<version>0.9.2-SNAPSHOT</version>
<artifactId>test-project-converter</artifactId>
<name>test-project</name>
<description>Test Project</description>
<dependencies>
<dependency>
<groupId>io.parent-dep</groupId>
<artifactId>parent-dev</artifactId>
<version>${project.parent.version}</version>
</dependency>
</dependencies>

Properties defined in parent pom cannot be resolved/updated in child pom

The parent pom:
<modelVersion>4.0.0</modelVersion>
<groupId>xx.xxxx.xxxx.xx</groupId>
<artifactId>parent-pom</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<properties>
<properties_deinfed_in_parent_pom>1.0.2-SNAPSHOT</properties_deinfed_in_parent_pom>
</properties>
The child pom:
<parent>
<groupId>xx.xxxx.xxxx.xx</groupId>
<artifactId>parent-pom</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>child-pom</artifactId>
<packaging>war</packaging>
<version>${properties_deinfed_in_parent_pom}</version>
which includes the parent pom, if I change the property properties_deinfed_in_parent_pom in parent pom, the version in child pom won't be updated. The only way I can update is using -Dxxx=value in maven command. I also checked the effective pom, it's also not updated. So will this idea work as my expectation, or what I thought was wrong.
I use Maven 3.3.x, IntelliJ 2018.1

The parent pom need to have the list of modules specified. Add the following to the parent pom
<modules>
<module>child-pom</module>
</modules>

Properties in parent definition are prohibited in the intellij maven on my mac osx

I have a question about my maven configuration on my MAC Intellij. I get an error that ${a-web.version} "properties in parent definition are prohibited" within parent tag in child POM.xml and that properties is defined in parent POM.xml.
But this same configuration works well on my Windows Intellij.
Below is my parent POM.xml.
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>***</groupId>
<artifactId>a-web</artifactId>
<packaging>pom</packaging>
<version>${a-web.version}</version>
<name>a-web project</name>
<url>http://***</url>
<properties>
<a-web.version>1.0.0</a-web.version>
</properties>
<modules>
<module>a-core</module>
<module>a-web</module>
</modules>
</project>
And this is my child POM.xml that configure a parent block.
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>a-web</artifactId>
<groupId>***</groupId>
<version>${a-web.version}</version>
<relativePath>../</relativePath>
</parent>
<artifactId>aweb-web</artifactId>
<version>${a-web.version}</version>
<packaging>war</packaging>
<name>aweb-web</name>
</project>
I've tried many methods from stackoverflow, but no one can fix it. I want to know why this Maven config have different behaviour in Mac and windows and how to fix it.

I have run into a very similar situation when the project started using parent version properties in the commit I have just pulled. The project would not build and felt "ill-imported". An attempt to show effective pom failed with no details presented by IDEA.
As #khmarbaise pointed out in the comments[1], there are some restrictions for properties usage in maven <parent> declarations - the most notable is maven 3.5+ is required. The IDEA might not be using maven new enough (the bundled one in the latest IDEA I have installed was too old) so I had to switch to local install using Settings > Build, Execution, Deployment > Build Tools > Maven > Maven Home Directory. Once pointed to newer version, it did not start to work immediately - some of the restart/rebuild/reimport routines caused the new setting to be effective and the project to successfully import and build again.
Despite the maven version requirement was enforced in pom, it have not caused IDEA to complain the maven version it uses is old. The lack of any details that IDEA fails to inspect the project with the maven it uses did not helped either. Now when everything else works, it still says "Properties in parent definition are prohibited" in pom files.
[1] https://maven.apache.org/maven-ci-friendly.html

Setting property revision in parent pom.xml and then inherit it into children, fixed the issue for me.
<groupId>com.java</groupId>
<artifactId>test</artifactId>
<version>${revision}</version>
<packaging>pom</packaging>
<name>Test</name>
<description>Demo project for Spring Boot</description>
<modules>
<module>backend</module>
<module>frontend</module>
</modules>
<properties>
<revision>1.0.0-SNAPSHOT</revision>
</properties>
In the child's pom.xml:
<parent>
<artifactId>com.java</artifactId>
<groupId>test</groupId>
<version>${revision}</version>
</parent>
<artifactId>backend</artifactId>
I use Maven 3.6.1

Work for me in Idea 18.2:
1) Don't use embeded Maven. Install Maven from official site! It's help me (^_^)
2) You can try to add groupId in child pom, put <groupId>com.iqiyi.lego.web</groupId> before line <artifactId>legoweb-web</artifactId>.
Try this code:
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>lego-web</artifactId>
<groupId>com.iqiyi.lego.web</groupId>
<version>${lego-web.version}</version>
<relativePath>../</relativePath>
</parent>
**<groupId>com.iqiyi.lego.web</groupId>**
<artifactId>legoweb-web</artifactId>
<version>${lego-web.version}</version>
<packaging>war</packaging>
<name>legoweb-web</name>
</project>

because your maven version is lower than 3.5.2, try to use version that >=3.5.2,when the ide intellij idea bundled maven version is lower than 3.5.2,try to download zip set to use your own maven instead of the bundled one.
by the way,although maven lower than 3.5.2 show error in intellij idea,but it works ok,you can "mvn package" success.

I think it's because when you push the compiled jar to central maven or private maven such as nexus, you can find the version in META-INF/maven/xxxxx/pom.xml of sub project is
<version>${lego-web.version}</version>
not real value <version>1.0.0</version>.so when you want to release a single jar, you cannot get the true version

It is the IntelliJ IDEA bug.
At least in the IntelliJ IDEA 2019.2 (Ultimate Edition)
Build #IU-192.5728.98, built on July 23, 2019

MavenError: Failed to execute goal on project: Could not resolve dependencies In Maven Multimodule project

I am trying to create a maven multi-module project. the project is created successfully but when I am trying to use one module as a dependency of another module, it throws an exception. When I create a module using eclipse, I was selecting packaging as a jar, but when the module is created, the packaging tag was not mention in child pom.xml and I manually insert the packaging tag as a jar.
following is my parent pom.xml:
<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.netsol</groupId>
<artifactId>empirecl</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
-------------------------
<modules>
<module>empirecl-web</module>
<module>empirecl-dao</module>
<module>empirecl-service</module>
<module>empirecl-api</module>
</modules>
Dao Child Module:
<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.netsol</groupId>
<artifactId>empirecl</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath>../pom.xml</relativePath>
</parent>
<artifactId>empirecl-dao</artifactId>
<packaging>jar</packaging>
<name>empirecl-dao</name>
------------------------
Service Child Module:
<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.netsol</groupId>
<artifactId>empirecl</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath>../pom.xml</relativePath>
</parent>
<artifactId>empirecl-service</artifactId>
<packaging>jar</packaging>
<name>empirecl-service</name>
<dependencies>
<dependency>
<groupId>com.netsol</groupId>
<artifactId>empirecl-dao</artifactId>
<version>0.0.1-SNAPSHOT</version>
<type>jar</type>
</dependency>
------------------------------------------
The Dao module maven clean and install successfully, but when i trying to use service module, it will generate an following exception:
[ERROR] Failed to execute goal on project empirecl-service: Could not resolve dependencies for project com.netsol:empirecl-service:jar:0.0.1-SNAPSHOT: Failed to collect dependencies at com.netsol:empirecl-dao:jar:0.0.1-SNAPSHOT: Failed to read artifact descriptor for com.netsol:empirecl-dao:jar:0.0.1-SNAPSHOT: Could not find artifact com.netsol:empirecl:pom:0.0.1-SNAPSHOT -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal on project empirecl-service: Could not resolve dependencies for project com.netsol:empirecl-service:jar:0.0.1-SNAPSHOT: Failed to collect dependencies at com.netsol:empirecl-dao:jar:0.0.1-SNAPSHOT
I am trying the find to solution from web, but still the solution is not found. In eclipse when i open the Dependency Hierarchy of service module, it shown the DAO module as a folder not jar. below is the screen shot of Dependency Hierarchy of service module.

In case anybody comes back to this, I think the problem here was failing to install the parent pom first, which all these submodules depend on, so the Maven Reactor can't collect the necessary dependencies to build the submodule.
So from the root directory (here D:\luna_workspace\empire_club\empirecl) it probably just needs a:
mvn clean install
(Aside: <relativePath>../pom.xml</relativePath> is not really necessary as it's the default value).

In my case I forgot it was packaging conflict jar vs pom. I forgot to write
<packaging>pom</packaging>
In every child pom.xml file

My solution was to insert <packaging>pom</packaging> between artifactId and version
<groupId>com.onlinechat</groupId>
<artifactId>chat-online</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>server</module>
<module>client</module>
<module>network</module>
</modules>

This what worked for me -
Go to Java build path --> Order and Export(check JRE system libraries and maven dependencies) in my case these 2 were unchecked.

My solution:
remove all projects in current workspace
import all again
maven update project (Alt + F5) -> Select All and check Force Update of Snapshots/Releases
maven build (Ctrl + B) until there is nothing to build
It worked for me after the second try.

For me, adding the following block of code under <dependency management><dependencies> solved the problem.
<dependency>
<groupId>org.glassfish</groupId>
<artifactId>javax.el</artifactId>
<version>3.0.1-b06</version>
</dependency>

Check with your VPN connection, if you are working in home.

Delete or close all other projects, and restart netbeans IDE, and try again.

Maven version with a property

I have big Maven (Tycho) project witch about 400 plug-ins.
We have specified version of application in each POM file.
Is there a way how to specify the version for all POM:s only on one place?
I would expect some think like:
<properties>
<buildVersion>1.1.2-SNAPSHOT</buildVersion>
</properties>
....
<version>${buildVersion}</version>
We have parent pom.xml:
<modelVersion>4.0.0</modelVersion>
<groupId>company</groupId>
<artifactId>build.parent</artifactId>
<version>1.1.2-SNAPSHOT</version>
<packaging>pom</packaging>
Then in each POM is reference to parent POM:
<parent>
<artifactId>build.parent</artifactId>
<groupId>company</groupId>
<relativePath>../build.parent/pom.xml</relativePath>
<version>1.1.2-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>company</groupId>
<artifactId>artifact</artifactId>
<version>1.1.2-SNAPSHOT</version>
<packaging>eclipse-plugin</packaging>

If you have a parent project you can set the version in the parent pom and in the children you can reference sibling libs with the ${project.version} or ${version} properties.
If you want to avoid to repeat the version of the parent in each children: you can do this:
<modelVersion>4.0.0</modelVersion>
<groupId>company</groupId>
<artifactId>build.parent</artifactId>
<version>${my.version}</version>
<packaging>pom</packaging>
<properties>
<my.version>1.1.2-SNAPSHOT</my.version>
</properties>
And then in your children pom you have to do:
<parent>
<artifactId>build.parent</artifactId>
<groupId>company</groupId>
<relativePath>../build.parent/pom.xml</relativePath>
<version>${my.version}</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>company</groupId>
<artifactId>artifact</artifactId>
<packaging>eclipse-plugin</packaging>
<dependencies>
<dependency>
<groupId>company</groupId>
<artifactId>otherartifact</artifactId>
<version>${my.version}</version>
or
<version>${project.version}</version>
</dependency>
</dependencies>
hth

The correct answer is this (example version):
In parent pom.xml you should have (not inside properties):
<version>0.0.1-SNAPSHOT</version>
In all child modules you should have:
<parent>
<groupId>com.vvirlan</groupId>
<artifactId>grafiti</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
So it is hardcoded.
Now, to update the version you do this:
mvn versions:set -DnewVersion=0.0.2-SNAPSHOT
mvn versions:commit # Necessary to remove the backup file pom.xml
and all your 400 modules will have the parent version updated.

Using a property for the version generates the following warning:
[WARNING]
[WARNING] Some problems were encountered while building the effective model for xxx.yyy.sandbox:Sandbox:war:0.1.0-SNAPSHOT
[WARNING] 'version' contains an expression but should be a constant. # xxx.yyy.sandbox:Sandbox:${my.version}, C:\Users\xxx\development\gwtsandbox\pom.xml, line 8, column 14
[WARNING]
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING]
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING]
If your problem is that you have to change the version in multiple places because you are switching versions, then the correct thing to do is to use the Maven Release Plugin that will do this for you automatically.

See the Maven - Users forum 'version' contains an expression but should be a constant. Better way to add a new version?:
here is why this is a bad plan.
the pom that gets deployed will not have the property value resolved, so
anyone depending on that pom will pick up the dependency as being the string uninterpolated with the ${ } and much hilarity will ensue in your
build process.
in maven 2.1.0 and/or 2.2.0 an attempt was made to deploy poms with
resolved properties... this broke more than expected, which is why those
two versions are not recommended, 2.2.1 being the recommended 2.x version.

With a Maven version of 3.5 or higher, you should be able to use a placeholder (e.g. ${revision}) in the parent section and inside the rest of the POM, you can use ${project.version}.
Actually, you can also omit GAV properties outside of <parent> which are the same, as they will be inherited. The result would look something like this:
<project>
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>build.parent</artifactId>
<groupId>company</groupId>
<version>${revision}</version> <!-- use placeholder -->
<relativePath>../build.parent</relativePath>
</parent>
<artifactId>artifact</artifactId>
<!-- no 'version', no 'groupId'; inherited from parent -->
<packaging>eclipse-plugin</packaging>
...
</project>
For more information, especially on how to resolve the placeholder during publishing, see Maven CI Friendly Versions | Multi Module Setup.

If you're using Maven 3, one option to work around this problem is to use the versions plugin
http://www.mojohaus.org/versions-maven-plugin/
Specifically the commands,
mvn versions:set -DnewVersion=2.0-RELEASE
mvn versions:commit
This will update the parent and child poms to 2.0-RELEASE. You can run this as a build step before.
Unlike the release plugin, it doesn't try to talk to your source control

I have two recommendation for you
Use CI Friendly Revision for all your artifacts. You can add -Drevision=2.0.1 in .mvn/maven.config file. So basically you define your version only at one location.
For all external dependency create a property in parent file. You can use Apache Camel Parent Pom as reference

I have successfully resolved the issue thus:
In parent pom.xml I have sited the version as usual (not inside properties):
<version>0.0.1-SNAPSHOT</version>
In all child modules I used:
<parent>
<groupId>com.example</groupId>
<artifactId>parent-module</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
Then I changed the parent to:
<version>0.0.2-SNAPSHOT</version>
Now, to update the version I executed in the command line:
mvn -N versions:update-child-modules
The children have been updated automatically to:
<parent>
<groupId>com.example</groupId>
<artifactId>parent-module</artifactId>
<version>0.0.2-SNAPSHOT</version>
</parent>
In other words I have used the versions:update-child-modules goal.
I have found this solution here.

The version of the pom.xml should be valid
<groupId>com.amazonaws.lambda</groupId>
<artifactId>lambda</artifactId>
<version>2.2.4 SNAPSHOT</version>
<packaging>jar</packaging>
This version should not be like 2.2.4. etc