@Override public Value solveEquation(final User user, final Calculation calculation) throws NimbitsException { final MathEvaluator m = new MathEvaluatorImpl(calculation.getFormula()); log.info(calculation.getFormula()); if (!Utils.isEmptyString(calculation.getX()) && calculation.getFormula().contains("x")) { // Point p = PointServiceFactory.getInstance().getPointByKey(calculation.getX()); final Entity p = EntityServiceFactory.getInstance() .getEntityByKey(user, calculation.getX(), EntityType.point) .get(0); if (p != null) { log.info("calc has an x car and i found " + p.getName()); final List<Value> val = ValueServiceFactory.getInstance().getCurrentValue(p); final double d = val.isEmpty() ? 0.0 : val.get(0).getDoubleValue(); m.addVariable("x", d); } else { log.severe("calc has an x car and x not found"); } } if (!Utils.isEmptyString(calculation.getY()) && calculation.getFormula().contains("y")) { final Entity p = EntityServiceFactory.getInstance() .getEntityByKey(user, calculation.getY(), EntityType.point) .get(0); // Point p = PointServiceFactory.getInstance().getPointByKey(calculation.getY()); if (p != null) { final List<Value> val = ValueServiceFactory.getInstance().getCurrentValue(p); final double d = val.isEmpty() ? 0.0 : val.get(0).getDoubleValue(); m.addVariable("y", d); } } if (!Utils.isEmptyString(calculation.getZ()) && calculation.getFormula().contains("z")) { final Entity p = EntityServiceFactory.getInstance() .getEntityByKey(user, calculation.getZ(), EntityType.point) .get(0); // Point p = PointServiceFactory.getInstance().getPointByKey(calculation.getZ()); if (p != null) { final List<Value> val = ValueServiceFactory.getInstance().getCurrentValue(p); final double d = val.isEmpty() ? 0.0 : val.get(0).getDoubleValue(); m.addVariable("z", d); } } final Double retVal = m.getValue(); if (retVal == null) { throw new NimbitsException("Formula returned a null value: " + calculation.getFormula()); } return ValueFactory.createValueModel(retVal, "CV"); }