Maven project not being treated as Java in Eclipse

Question

I\'m working on a project that has lots of different Maven projects. I\'ve been doing a bunch of JUnit testing on these projects, and usually this goes well. I open up Eclipse

Answer 1

Several of the existing answers should work, but those suggesting to add a Java facet will only work if your project already is of (or you want to convert it to) a faceted nature, and the one suggesting you change your pom.xml will only work if you then re-import your project as a maven project.

If you'd like to "fix" your existing project, i.e. add a Java nature without converting it to faceted form and without deleting and re-importing, just edit your .project file (externally, or with the Navigator view in eclipse, as it won't show up in your package explorer) and add the java builder and java nature to the existing maven builder/nature:

    yourprojectname
    
    
    
    
        
        
            org.eclipse.jdt.core.javabuilder
            
            
        
        
        
            org.eclipse.m2e.core.maven2Builder
            
            
        
    
    
        
        org.eclipse.jdt.core.javanature
        
        org.eclipse.m2e.core.maven2Nature
    

Note the different capitalisation (javabuilder but maven2Builder, javanature but maven2Nature).

As soon as you save, it should re-build automatically. You may have to manually add any source folders (Project properties -> Java Build Path -> Source tab -> Add Folder....