Those classes are intented for users dealing with SAT solvers as blackboxes. Typical usage is the following:
    DimacsSolver solver = new Dimacs(SolverFactory.newMiniLearning());
    
    try {
        solver.parseInstance("myfile.cnf");    
        if (solver.isSatisfiable()) {
    	    // SAT case
        } else {
    	    // UNSAT case
        }
    } catch (FileNotFoundException e) {
      // file not found
    } catch (ParseFormatException e) {
      // pbm in Dimacs format
    } catch (IOException e) {
      // Other IO Exception
    } catch (ContradictionException e) {
      // Trivial UNSAT case
    }