bundles/org.simantics.modeling/src/org/simantics/modeling/scl/GraphRelation.java

   1 package org.simantics.modeling.scl;\r
   2 \r
   3 import org.simantics.db.Resource;\r
   4 import org.simantics.scl.compiler.common.names.Name;\r
   5 import org.simantics.scl.compiler.elaboration.expressions.EApply;\r
   6 import org.simantics.scl.compiler.elaboration.expressions.EExternalConstant;\r
   7 import org.simantics.scl.compiler.elaboration.expressions.EVariable;\r
   8 import org.simantics.scl.compiler.elaboration.expressions.Expression;\r
   9 import org.simantics.scl.compiler.elaboration.expressions.Variable;\r
  10 import org.simantics.scl.compiler.elaboration.query.compilation.EnforcingContext;\r
  11 import org.simantics.scl.compiler.elaboration.query.compilation.QueryCompilationContext;\r
  12 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;\r
  13 import org.simantics.scl.compiler.errors.Locations;\r
  14 import org.simantics.scl.compiler.types.TVar;\r
  15 import org.simantics.scl.compiler.types.Type;\r
  16 import org.simantics.scl.compiler.types.Types;\r
  17 \r
  18 public class GraphRelation implements SCLRelation {\r
  19 \r
  20     Resource relation;\r
  21     double relationSelectivity;\r
  22     Resource inverseRelation;\r
  23     double inverseRelationSelectivity;\r
  24     \r
  25     public GraphRelation(Resource relation, double relationSelectivity,\r
  26             Resource inverseRelation, double inverseRelationSelectivity) {\r
  27         this.relation = relation;\r
  28         this.relationSelectivity = relationSelectivity;\r
  29         this.inverseRelation = inverseRelation;\r
  30         this.inverseRelationSelectivity = inverseRelationSelectivity;\r
  31     }\r
  32 \r
  33     @Override\r
  34     public TVar[] getTypeVariables() {\r
  35         return TVar.EMPTY_ARRAY;\r
  36     }\r
  37     \r
  38     private static final Type[] PARAMETER_TYPES = new Type[] { Types.RESOURCE, Types.RESOURCE };\r
  39     \r
  40     @Override\r
  41     public Type[] getParameterTypes() {\r
  42         return PARAMETER_TYPES;\r
  43     }\r
  44 \r
  45     @Override\r
  46     public double getSelectivity(int boundVariables) {\r
  47         switch(boundVariables) {\r
  48         case FF: return Double.POSITIVE_INFINITY;\r
  49         case BF: return relationSelectivity;\r
  50         case FB: return inverseRelation == null ? Double.POSITIVE_INFINITY : inverseRelationSelectivity;\r
  51         case BB: return 0.1;\r
  52         default: throw new IllegalArgumentException();\r
  53         }\r
  54     }\r
  55     \r
  56     @Override\r
  57     public int getRequiredVariablesMask() {\r
  58         return inverseRelation == null ? BF : FF;\r
  59     }\r
  60     \r
  61     private static final Name GET_OBJECTS = Name.create("Simantics/DB", "#");\r
  62     private static final Name HAS_STATEMENT = Name.create("Simantics/DB", "existsStatement3");\r
  63     \r
  64     @Override\r
  65     public void generate(long location, QueryCompilationContext context,\r
  66             Type[] typeParameters, Variable[] parameters, int boundVariables) {\r
  67         switch(boundVariables) {\r
  68         case BF: \r
  69             context.iterateList(parameters[1], new EApply(\r
  70                     Locations.NO_LOCATION,\r
  71                     Types.READ_GRAPH,\r
  72                     context.getTypingContext().getConstant(GET_OBJECTS),\r
  73                     new EVariable(parameters[0]),\r
  74                     new EExternalConstant(relation, Types.RESOURCE)\r
  75                     ));\r
  76             break;\r
  77         case FB:\r
  78             if(inverseRelation == null)\r
  79                 throw new IllegalArgumentException();\r
  80             context.iterateList(parameters[0], new EApply(\r
  81                     Locations.NO_LOCATION,\r
  82                     Types.READ_GRAPH,\r
  83                     context.getTypingContext().getConstant(GET_OBJECTS),\r
  84                     new EVariable(parameters[1]),\r
  85                     new EExternalConstant(inverseRelation, Types.RESOURCE)\r
  86                     ));\r
  87             break;\r
  88         case BB:\r
  89             context.condition(\r
  90                     inverseRelation == null || relationSelectivity <= inverseRelationSelectivity\r
  91                     ? new EApply(\r
  92                             Locations.NO_LOCATION,\r
  93                             Types.READ_GRAPH,\r
  94                             context.getTypingContext().getConstant(HAS_STATEMENT),\r
  95                             new Expression[] {\r
  96                                 new EVariable(parameters[0]),\r
  97                                 new EExternalConstant(relation, Types.RESOURCE),\r
  98                                 new EVariable(parameters[1])\r
  99                             }\r
 100                             )\r
 101                     : new EApply(\r
 102                             Locations.NO_LOCATION,\r
 103                             Types.READ_GRAPH,\r
 104                             context.getTypingContext().getConstant(HAS_STATEMENT),\r
 105                             new Expression[] {\r
 106                                 new EVariable(parameters[1]),\r
 107                                 new EExternalConstant(inverseRelation, Types.RESOURCE),\r
 108                                 new EVariable(parameters[0])\r
 109                             }\r
 110                             ));\r
 111             break;\r
 112         default: throw new IllegalArgumentException();\r
 113         }\r
 114     }\r
 115 \r
 116     private static final Name CLAIM = Name.create("Simantics/DB", "claim");\r
 117     \r
 118     @Override\r
 119     public Expression generateEnforce(long location, EnforcingContext context,\r
 120             Type[] typeParameters, Variable[] parameters) {\r
 121         return new EApply(\r
 122                 Locations.NO_LOCATION,\r
 123                 Types.WRITE_GRAPH,\r
 124                 context.getTypingContext().getConstant(CLAIM),\r
 125                 new EVariable(parameters[0]),\r
 126                 new EExternalConstant(relation, Types.RESOURCE),\r
 127                 new EVariable(parameters[1])\r
 128                 );\r
 129     }\r
 130 \r
 131     @Override\r
 132     public int getPhase() {\r
 133         return 0;\r
 134     }\r
 135 \r
 136 }\r