A cycle was detected in the build path of project xxx - Build Path Problem
Solution 1:
Mark circular dependencies as "Warning" in Eclipse tool to avoid "A CYCLE WAS DETECTED IN THE BUILD PATH" error.
In Eclipse go to:
Windows -> Preferences -> Java-> Compiler -> Building -> Circular Dependencies
Solution 2:
When we have multiple projects in workspace, we have to set the references between the projects, not among the projects. If P1 references P2, P2 references P3, and P3 reference back to P1. That will cause a cycle.
The Solution is to draw a Diagram of the reference between projects in workspace. Check the Java Build Path of each of the projects to see the Tab of the Projects window. Take out the Project that are refering back to the main project, e.g. P3 references P1, in this example above.
Detailed operation is to select P3 project in RAD OR eclipse, right click on the project and choose the properties option, it brings up a new window for properties of P3. Click on the "Java Build Path" section, Choose the "Projects" option Tab. You can see the P3 has referenced P1 in the field. Select the P1 reference, click "Remove" button on the right side of the window. Then, click okay. The IDE will start to reset the path automatically.
Done.
Keep find all of the mis-referenced reference in every each projects until you have the right references to each of the projects in your Diagram. Good Luck!
Solution 3:
I had this due to one project referencing another.
- Remove reference from project A to project B
- Try running stuff, it will break
- Re-add reference
- Clean/Clean and build
- Back in business
Solution 4:
In simple terms, a cycle is when bundle A depends on bundle B which depends on bundle A. If this is source code, then there's no way of building the bundles seperately in one pass.
Since the problem only shows in Eclipse, it may be a binary circular dependency as opposed to a source code circular dependency.
There is support for binary cycles in recent versions of Eclipse: Eclipsesource Blog
If the cycle is in your code, then I suggest refactoring the code by breaking out some of the code to a 3rd bundle to remove the circular dependency.
And watch out if you are using OSGi fragments (a common pattern for unit testing) as it is very easy to introduce cycles.
Eclipse's manifest editor does have functionality on the "Dependencies" tab for looking for cycles (you need to click on "Dependency Analysis"), but I've never seen it show a cycle even when Eclipse has a big red X telling me there's a cycle!