bundles/org.simantics.modeling.ui/src/org/simantics/modeling/ui/expression/BasicExpression.java

   1 package org.simantics.modeling.ui.expression;
   2
   3 import org.simantics.basicexpression.Expressions;
   4 import org.simantics.databoard.binding.Binding;
   5 import org.simantics.databoard.Bindings;
   6 import org.simantics.db.ReadGraph;
   7 import org.simantics.db.Resource;
   8 import org.simantics.db.WriteGraph;
   9 import org.simantics.db.exception.DatabaseException;
  10 import org.simantics.db.layer0.variable.EquationExpression;
  11 import org.simantics.db.layer0.variable.Expression;
  12 import org.simantics.db.layer0.variable.Variable;
  13 import org.simantics.utils.datastructures.Triple;
  14
  15 public class BasicExpression implements Expression, EquationExpression {
  16
  17         final private Resource expression;
  18
  19         public BasicExpression(Resource expression) {
  20                 this.expression = expression;
  21         }
  22
  23         @Override
  24         public <T> T evaluate(ReadGraph graph, Variable property, Binding binding) throws DatabaseException {
  25                 return evaluate(graph, property);
  26         }
  27
  28         @SuppressWarnings("unchecked")
  29     @Override
  30         public <T> T evaluate(ReadGraph graph, Variable property) throws DatabaseException {
  31
  32                 String expressionString = graph.getValue(expression, Bindings.STRING);
  33                 BasicExpressionVisitor visitor = new BasicExpressionVisitor(graph, property);
  34                 Expressions.evaluate(expressionString, visitor);
  35                 return (T)visitor.getResult();
  36
  37         }
  38
  39         @Override
  40         public <T> void invert(WriteGraph graph, Variable property, T value, Binding binding) throws DatabaseException {
  41
  42                 String expressionString = graph.getValue(expression, Bindings.STRING);
  43                 InvertBasicExpressionVisitor visitor = new InvertBasicExpressionVisitor();
  44                 Expressions.evaluate(expressionString, visitor);
  45                 Object pair = visitor.getResult();
  46                 if(pair instanceof Triple) {
  47                         @SuppressWarnings("unchecked")
  48                         Triple<Double, Double, String> data = (Triple<Double, Double, String>)pair;
  49                         if(Math.abs(data.first) > 1e-9) {
  50                                 Double inverted = ((Double)value - data.second) / data.first;
  51                                 String target = data.third;
  52                                 Variable targetVariable = property.browse(graph, target);
  53 //                              System.out.println("invert: " + target + " = " + property.browse(graph, target).getURI(graph));
  54                                 targetVariable.setValue(graph, inverted, binding);
  55                         }
  56                 }
  57
  58         }
  59
  60         @Override
  61         public boolean isInvertible(ReadGraph graph, Variable property) throws DatabaseException {
  62
  63                 String expressionString = graph.getValue(expression, Bindings.STRING);
  64                 InvertBasicExpressionVisitor visitor = new InvertBasicExpressionVisitor();
  65                 Expressions.evaluate(expressionString, visitor);
  66                 Object value = visitor.getResult();
  67                 if(value instanceof Triple) return true;
  68                 else return false;
  69
  70         }
  71
  72 }