I have the following dependency (only so far) pom.xml
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.6.2.RELEASE</version>
</dependency>
This dependency obviously depends on other "dependencies" via it's pom.xml... when maven finished downloading these dependencies I noticed that it didn't grab the latest version of the Spring stuff (4.0.6.RELEASE)... it grabbed a 3.2.x version.
How can I force maven to grab the latest version of the Spring stuff? Do I need to explicitly modify my pom.xml to include all the dependencies or is there some "magic" I can use for this?
Thanks.
Spring "Bill Of Materials"
Salvation may come from special "bill of materials" POMs supported by Maven and published by Spring. Quoting from Maven "Bill Of Materials" Dependency in their manual:
It is possible to accidentally mix different versions of Spring JARs when using Maven. For example, you may find that a third-party library, or another Spring project, pulls in a transitive dependency to an older release. If you forget to explicitly declare a direct dependency yourself, all sorts of unexpected issues can arise.
To overcome such problems Maven supports the concept of a "bill of materials" (BOM) dependency. You can import the spring-framework-bom in your dependencyManagement section to ensure that all spring dependencies (both direct and transitive) are at the same version.
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-framework-bom</artifactId>
<version>4.0.6.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
Would this work for you?
Looking at the spring-data-jpa artifact pom file, we can see that it has a parent called spring-data-parent with current version 1.4.2.RELEASE. It's pom describes dependencies and their versions. Currently spring version is at 3.2.10.RELEASE
One way you can possibly accomplish what you want is to add explicit dependency on spring artifacts. But you would still have to define their versions.
Related
I have dependency in pom with groovy-all
<dependency>
<groupId>org.codehaus.groovy</groupId>
<artifactId>groovy-all</artifactId>
<version>3.0.7</version>
<type>pom</type>
</dependency>
But if I check libs inside, I see 2.5.13 versions. How can I change all of this libs to 3.0.7? Of course I can add separately, but maybe is another option?
The versions are managed in the <dependencyManagement> section of the POM, either directly or by using a BOM (scope import).
If you want to update them, you need to look there.
You are importing Groovy 2.5.13 elsewhere likely as a transitive dependency and maven is deciding to use 2.5.13 instead of 3.0.7.
Look at the groovy 3.0.7 pom:
https://repo1.maven.org/maven2/org/codehaus/groovy/groovy-all/3.0.7/groovy-all-3.0.7.pom
It has no reference to 2.5.13.
in spring boot project tomcat-embed-core: 9.0.12 is getting resolved by parent dependency spring-boot-starter-web:2.1.0.
but due to some reasons we have to upgrade the tomcat-embed-core version from 9.0.12 to 9.0.20.
I have added the below dependency separately in POM,
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-core</artifactId>
<version>9.0.20</version>
</dependency>
now I can see V9.0.20 in dependency hierarchy, but also omitted for conflict with 9.0.20.
is this a correct way, if no then suggest the best way to do this?
I am trying to understand maven a little more. How is maven able to download the dependencies of the main dependency of the application? For example assuming my application has main dependency like this:
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
<version>2.7.0</version>
<scope>provided</scope>
</dependency>
Now, when maven downloads this jar , it downloads the dependencies for this jar as well. For example, see the screen shot below:
As can be seen, maven has not only downloaded the hadoop-hdfs-2.7.0.jar but also all it dependencies.
Now, my questions is how maven knows what are the dependencies for the "top-level" dependency, that is in this case the "top-level" dependency is hadoop-hdfs, so what all jars it has to download for this?
I see this as well in the .m2/respository for hadoop-hdfs:
I opened the .pom file, the contents are (partly):
<project>
....
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
<version>2.7.0</version>
<description>Apache Hadoop HDFS</description>
<name>Apache Hadoop HDFS</name>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-annotations</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-auth</artifactId>
<scope>provided</scope>
</dependency>
<dependencies>
...
</project>
What is this hadoop-hdfs-2.7.0.pom ? Does this file give information to maven what are the dependencies to be downloaded for hadoop-hdfs-2.7.0.jar?
Can anyone help me clear these things?
First of all you are right, the hadoop-hdfs-2.7.0.pom tells Maven
about the libraries that hadoop depends upon. But, when using hadoop
as a dependency in your project, maven uses the below strategies to
finalize the list of dependencies in addition to using the
hadoop-hdfs-2.7.0.pom.
If a dependency is specified with groupid, artifactid and version in the current project under the dependencies tag, it takes the first
precedence. This is how hadoop-hdfs got added in your project.
Dependency Management takes the next precedence. When a dependency is specified only with group and artifact id's under dependencies tag
but at the same time, the dependency is defined under
dependencyManagement tag with version and transitively inside hadoops pom.xml also,
the one under the dependencyManagement tag will be given preference.
Dependency Mediation takes the last precedence. Dependencies are resolved using dependency mediation. Meaning, in your case the
dependencies mentioned inside hadoop-hdfs-2.7.0.pom are the transitive
dependencies (indirectly depends on these dependencies since your
dependency "hadoop-hdfs" requires it) of your project and this process continues
recursively until all child dependencies are resolved.
Note: There are other features such as excluding dependencies, marking
one optional and importing a list of dependencies. But they are used
sparsely. More information with examples can be found in the below URL
[https://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html#Dependency_Management][1]
My project is a fairly large project consisting of many maven modules (but not microservices). I was trying to do Moving from spring to spring-bom on WAS but seems lot of clashes in versions. So for example one of my modules is using commons-collectionsversion 2.6.0 and my current project is using 3.2.2. I want the same jar to be used across. Since its more of a migration project I cannot do changes in container or repository changes at this time. I should only make sure that all the version are compatible with each other. My plan :
I want to include a dependency which is with in some other dependency
into the current pom as a dependency.
Also I want other jars in this pom (which exists as a dependency) to included the dependency
Is there anyway to do it?
I didn't completely understand your question, but the can help you to define a cross-module dependency version, as long as you place it in the parent-pom file.
<dependencyManagement>
<dependency>
<groupId>com.group</groupId>
<artifactId>project-1</artifactId>
<version>1.0.0</version>
</dependency>
</dependencyManagement>
and then define the dependency in the relevant module without providing it a version (it will be inherited from the parent-pom's <dependencyManagment> tag:
<dependencies>
<dependency>
<groupId>com.group</groupId>
<artifactId>project-1</artifactId>
</dependency>
</dependencies>
Problem is a bit stupid but I can't find any spring3.0-with-dependencies.jar. Is it assumed that I should find all necessary dependencies by myself?
May I use dependencies from spring 2.5 in this case? UPD: answer is no, I can't. So, where are the dependencies??
I guess they don't release them any more. You can have the dependencies automatically if you use maven or ivy. All you need is to define the dependencies in your pom.xml like this:
<pom>
...
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>3.0.0.RELEASE</version>
</dependency>
</dependencies>
...
</pom>
Maven will bring all the dependencies transitively.
If you are using Maven, you can get Spring 3.0 jars (and their transitive dependencies) from the central repository. Simply add this to your pom.xml:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.0.0.RELEASE</version>
</dependency>
For more details, more artifacts, check out Obtaining Spring 3 Artifacts with Maven (and please, don't use EBR if you don't need it or I guarantee the nightmare).
Usually the readme.txt file has the dependencies listed for each module. With that you can usually get them easiest from the maven repository... or better yet, with maven (http://maven.apache.org).