code: protected String resolveVersion(final MavenDependency dependency) throws IllegalArgumentException {
          final String declaredVersion = dependency.getVersion();
          if (Validate.isNullOrEmpty(declaredVersion)) {
              throw new ResolutionException(MessageFormat.format(
                  "Unable to get version for dependency specified by {0}:, it was either null or empty.",
                  dependency.toCanonicalForm()));
          }
          return declaredVersion;
      }
docs: Use available information to resolve the version for the specified {@link MavenDependency}
  
  @param dependency A {@link MavenDependency} the version should be resolved for
  @return The resolved version
  @see org.jboss.shrinkwrap.resolver.impl.maven.ResolveStageBaseImpl#resolveVersion(org.jboss.shrinkwrap.resolver.api.maven.coordinate.MavenDependency)