bundles/org.simantics.equation/src/org/simantics/equation/solver/Solver.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.equation.solver;
  13
  14 import java.util.Collection;
  15 import java.util.HashMap;
  16 import java.util.Map;
  17
  18 import org.simantics.db.ReadGraph;
  19 import org.simantics.db.Resource;
  20 import org.simantics.db.WriteGraph;
  21 import org.simantics.db.exception.DatabaseException;
  22 import org.simantics.equation.EquationResources;
  23
  24
  25 public class Solver {
  26
  27     private static Map<Resource,ExpressionSolver> solvers = new HashMap<Resource, ExpressionSolver>();
  28
  29
  30     public static void addSolver(Resource res, ExpressionSolver solver) {
  31         if (res == null || solver == null)
  32             throw new NullPointerException("Expression solver must be bound to valid resource");
  33         solvers.put(res, solver);
  34     }
  35
  36     public void evaluate(ReadGraph g, Resource r) throws DatabaseException {
  37         if (g.isInstanceOf(r, EquationResources.equationResource.Expression)) {
  38             Collection<Resource> types = g.getTypes(r);
  39             ExpressionSolver solver = null;
  40
  41             for (Resource res : types) {
  42                 solver = solvers.get(res);
  43                 if (solver != null)
  44                     break;
  45             }
  46             solver.evaluate(this, g, r);
  47         } else {
  48             throw new IllegalArgumentException("Input is not an equation");
  49         }
  50     }
  51
  52     Map<Resource,Object> valueMap = new HashMap<Resource,Object>();
  53
  54     public Object getCachedValue(Resource res) {
  55         return valueMap.get(res);
  56     }
  57
  58     public void setValue(Resource res, Object o) {
  59         valueMap.put(res, o);
  60     }
  61
  62     public void clear() {
  63         valueMap.clear();
  64     }
  65
  66     public double getDoubleValue(ReadGraph g, Resource d) throws DatabaseException {
  67         Object o = getValue(g, d);
  68         if (o instanceof double[])
  69             return ((double[])o)[0];
  70         if (o instanceof float[])
  71             return ((float[])o)[0];
  72         if (o instanceof int[])
  73             return ((int[])o)[0];
  74         if (o instanceof long[])
  75             return ((long[])o)[0];
  76         throw new RuntimeException("Cannot cast object to double " + o + "  " + o.getClass());
  77     }
  78
  79     public Object getValue(ReadGraph graph, Resource res) throws DatabaseException {
  80         Object o = getCachedValue(res);
  81         if (o == null) {
  82             o = graph.getValue(res);
  83         }
  84         return o;
  85     }
  86
  87     public void pushToGraph(WriteGraph graph) throws DatabaseException {
  88         for (Resource r : valueMap.keySet()) {
  89             if (graph.isInstanceOf(r, EquationResources.builtins.Literal)) {
  90                 Object value = valueMap.get(r);
  91                 if (value instanceof boolean[] ||
  92                         value instanceof byte[] ||
  93                         value instanceof int[] ||
  94                         value instanceof long[] ||
  95                         value instanceof float[] ||
  96                         value instanceof double[] ||
  97                         value instanceof String[])
  98                     graph.claimValue(r, value);
  99                 else {
 100                     throw new RuntimeException("Internal error, unknown datatype " + value.getClass());
 101                 }
 102             }
 103         }
 104     }
 105
 106 }