elk-reasoner/src/main/java/org/semanticweb/elk/reasoner/stages/ClassExpressionQueryState.java
boolean isSatisfiable(final ElkClassExpression classExpression)
			throws ElkQueryException {
		final QueryState state = checkComputed(classExpression);
		return state.node != null;
	}
boolean isSatisfiable(final ElkClassExpression classExpression)
			throws ElkQueryException {
		final QueryState state = checkComputed(classExpression);
		return state.node != null;
	}
Checks whether the supplied class expression is satisfiable, if the
result was already computed. If the class expression was not registered
by {@link #registerQuery(ElkClassExpression)} or the appropriate stage
was not completed yet, throws {@link ElkQueryException}.

@param classExpression
@return whether the supplied class expression is satisfiable.
@throws ElkQueryException
if the result is not ready