bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/adapter/ContextualRelatedValue.java

   1 package org.simantics.db.layer0.adapter;
   2
   3 import org.simantics.db.ConverterComputationalValue;
   4 import org.simantics.db.ReadGraph;
   5 import org.simantics.db.Resource;
   6 import org.simantics.db.exception.DatabaseException;
   7 import org.simantics.db.exception.RuntimeDatabaseException;
   8 import org.simantics.db.layer0.variable.Variable;
   9 import org.simantics.scl.runtime.SCLContext;
  10 import org.simantics.scl.runtime.function.Function1;
  11 import org.simantics.scl.runtime.function.FunctionImpl3;
  12
  13 abstract public class ContextualRelatedValue implements ConverterComputationalValue {
  14
  15     @SuppressWarnings("unchecked")
  16         @Override
  17     public <T> T getValue(ReadGraph graph, Resource resource) throws DatabaseException {
  18
  19         return (T)new FunctionImpl3<ReadGraph, Resource, Object, Object>() {
  20
  21             @Override
  22             public Object apply(ReadGraph graph, Resource converter, Object context) {
  23                 SCLContext sclContext = SCLContext.getCurrent();
  24                 Object oldGraph = sclContext.get("graph");
  25                 try {
  26                     if(context instanceof Variable) {
  27                         Variable variable = (Variable)context;
  28                         try {
  29                             Function1<Object,Object> fn = getFunction(graph, variable.getParent(graph).getRepresents(graph), variable.getRepresents(graph), variable.getPredicateResource(graph));
  30                             sclContext.put("graph", graph);
  31                             return fn.apply(variable);
  32                         } catch (DatabaseException e) {
  33                             throw new RuntimeDatabaseException(e);
  34                         }
  35                     } if (context instanceof Resource) {
  36                         Resource resource = (Resource)context;
  37                         try {
  38                             /*
  39                              * Here converter is the object and context is the subject
  40                              */
  41                                 Function1<Object,Object> fn = getFunction(graph, resource, converter, null);
  42                             return fn.apply(resource);
  43                         } catch (DatabaseException e) {
  44                             throw new RuntimeDatabaseException(e);
  45                         }
  46                     } else {
  47                         throw new IllegalStateException("Unknown context " + context);
  48                     }
  49                 } finally {
  50                     sclContext.put("graph", oldGraph);
  51                 }
  52             }
  53
  54         };
  55
  56     }
  57
  58 }