For Maven projects you can go like this:

Open the maven the tool window. In Intellij you can do this by right click on the project name and then click on "maven tool window".

Then click on the reimport all maven projects.

Now your project should be stable again



Intellij has a lot of interesting features and for that it makes use of cache. That sometimes makes problems like this. After invalidating caches and restarting IntelliJ the dependencies that were cached are removed and updated on the next compiling, and these errors were fixed.

IntelliJ not recognizing classes of other maven modules

I am developing an application with multiple java modules and when I try to use class of another module, that I have a dependency on java does not recognize it. It used to recognize it, but since I updated versions of the modules this does not work. I tried reimporting everything, but it doesn't work. I am working on IntelliJ

Using Maven and Gradle through proxy

Because of my working environment, I have to set up Gradle and Maven to use a proxy server without password authentication. Only setting up the operating system to use a proxy is not sufficient, as I cannot establish network communication using Maven or Gradle. How can I configure the tools to communicate through a proxy?

CRUD operations example using Spring, MVC, Hybernate and Maven

I need an example to better understand of how to operate with these technologies. The interface will be HTML-based. The application will support all CRUD operations: create, read, update, delete. MySQL was used for the database.

Using Maven to Compile those Projects

The solution to that problem is quite simple, you just have to install maven (if you haven't done it already) and then compile the projects with e.g. "mvn eclipse:eclipse".

In the beginning, it takes maven approx. 30 minutes to download all dependencies and required files but then is able to compile it without any problems..


Fixing the Import Problem in Mule ESB

If you are programming with the MuleESB suite you are may be forced with the problem, that it is not able to find imports or throws "ClassNotFoundExceptions" after trying to compile your source code. Even after checking the class/build path and adding every jar to them, the problem still exists.

Adding a new maven mirror and overwrite the default behavior

At the user's home directory (e.g. C:\Users\\ on a Windows machine, or /Users/ on a Mac) there is a hidden directory, called .m2. Within this directory there is a settings.xml file. It may be that this file is not existing, than just create a new text file and save it as settings.xml

Withing the XML file, the following notation allows to manually specify a mirror: see attached image.

The reference of the xml elements is:
mirrorOf: The server ID of the repository being mirrored (e.g "central")
name: A name of the mirror (optional, just for documentation purpose)
url: The url of the mirror
id: A freely selectable id of the mirror entry

Please check the attached file for an example.


Adding different mirrors for maven / Mirror management in Apache maven

In some cases it may takes a lot of time during a maven build as it is necessary to download required dependecies from the maven central repo. Maven uses a mirror, located in California, United States for downlowding required maven dependencies during a maven bulid. Even there has been implemented a balance loader for the default maven mirror ( recently it might make sense to overwrite the default behavior and set the mirror manually cause of: -) A mirror is geographically closer and faster -) Use an internal mirror (e.g. repo - proxy) Maven allows different settings to improve speed and make the downloading process more efficient and fast. Depending on the workflow two different soultions can be an adequate approach for the problem, described above.

Twitter your project status with Maven.

Create a simple hello world Java Maven Project (this is already available as an maven-archetype) and configure it in a way so that every time you make a installation (via the cli command: mvn clean install) a new status update with the message "New Project Built Available" shows up on your twitter account.
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