bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/variable/StandardRVIResolver.java

   1 package org.simantics.db.layer0.variable;
   2
   3 import org.simantics.databoard.Bindings;
   4 import org.simantics.databoard.Databoard;
   5 import org.simantics.databoard.binding.Binding;
   6 import org.simantics.datatypes.literal.GUID;
   7 import org.simantics.db.ReadGraph;
   8 import org.simantics.db.Resource;
   9 import org.simantics.db.exception.DatabaseException;
  10 import org.simantics.db.layer0.exception.MissingVariableException;
  11 import org.simantics.db.layer0.request.VariablePossibleRVIRequest;
  12 import org.simantics.db.layer0.request.VariableRVIRequest;
  13 import org.simantics.db.layer0.variable.RVI.GuidRVIPart;
  14 import org.simantics.db.layer0.variable.RVI.RVIPart;
  15 import org.simantics.db.layer0.variable.RVI.ResourceRVIPart;
  16 import org.simantics.db.layer0.variable.RVI.StringRVIPart;
  17 import org.simantics.db.layer0.variable.Variables.Role;
  18 import org.simantics.layer0.Layer0;
  19
  20 public class StandardRVIResolver implements RVIResolver {
  21
  22     public static final StandardRVIResolver INSTANCE = new StandardRVIResolver();
  23
  24     protected RVIPart getRVIPart(ReadGraph graph, Variable variable) throws DatabaseException {
  25         if(variable instanceof AbstractVariable) {
  26             AbstractVariable abst = (AbstractVariable)variable;
  27             return abst.getRVIPart(graph);
  28         }
  29         Role role = variable.getRole(graph);
  30         return new StringRVIPart(role, variable.getName(graph));
  31     }
  32
  33     @Override
  34     public RVI getRVI(ReadGraph graph, Variable variable) throws DatabaseException {
  35         if(Variables.isContext(graph, variable)) {
  36             Databoard databoard = graph.getService( Databoard.class );
  37             Binding rviBinding = databoard.getBindingUnchecked( RVI.class );
  38             return RVI.empty( rviBinding );
  39         } else {
  40             Variable parent = variable.getParent(graph);
  41             if (parent == null)
  42                 // TODO: consider using a more suitable exception here to better convey the situation.
  43                 throw new MissingVariableException("no parent for variable " + variable + " (URI=" + variable.getURI(graph) + ")", variable.getPossibleRepresents(graph));
  44             RVI base = graph.syncRequest(new VariableRVIRequest(parent));
  45             RVIPart part = getRVIPart(graph, variable);
  46             return new RVIBuilder(base).append(part).toRVI();
  47         }
  48     }
  49
  50     @Override
  51     public RVI getPossibleRVI(ReadGraph graph, Variable variable) throws DatabaseException {
  52         if(Variables.isContext(graph, variable)) {
  53             Databoard databoard = graph.getService( Databoard.class );
  54             Binding rviBinding = databoard.getBindingUnchecked( RVI.class );
  55             return RVI.empty( rviBinding );
  56         } else {
  57             Variable parent = variable.getParent(graph);
  58             if (parent == null) return null;
  59             RVI base = graph.syncRequest(new VariablePossibleRVIRequest(parent));
  60             if (base == null) return null;
  61             RVIPart part = getRVIPart(graph, variable);
  62             return new RVIBuilder(base).append(part).toRVI();
  63         }
  64     }
  65
  66     protected Variable resolveChild(ReadGraph graph, Variable variable, Resource resource) throws DatabaseException {
  67         String rName = graph.getRelatedValue(resource, Layer0.getInstance(graph).HasName, Bindings.STRING);
  68         return variable.getChild(graph, rName);
  69     }
  70
  71     protected Variable resolveProperty(ReadGraph graph, Variable variable, Resource resource) throws DatabaseException {
  72         String rName = graph.getRelatedValue(resource, Layer0.getInstance(graph).HasName, Bindings.STRING);
  73         return variable.getProperty(graph, rName);
  74     }
  75
  76     protected Variable resolveChild(ReadGraph graph, Variable variable, GuidRVIPart part) throws DatabaseException {
  77         return resolveChildDefault(graph, variable, part);
  78     }
  79
  80     protected Variable resolveProperty(ReadGraph graph, Variable variable, GuidRVIPart part) throws DatabaseException {
  81         return resolvePropertyDefault(graph, variable, part);
  82     }
  83
  84     public static Variable resolveChildDefault(ReadGraph graph, Variable variable, GuidRVIPart part) throws DatabaseException {
  85                 Layer0 L0 = Layer0.getInstance(graph);
  86         for(Variable child : variable.getChildren(graph)) {
  87                 GUID id = child.getPossiblePropertyValue(graph, L0.identifier, GUID.BINDING);
  88                 if(id != null) {
  89                         if(id.mostSignificant == part.mostSignificant && id.leastSignificant == part.leastSignificant)
  90                                 return child;
  91                 }
  92         }
  93         throw new MissingVariableException("Could not resolve child " + part, variable.getPossibleRepresents(graph));
  94     }
  95
  96     public static Variable resolvePropertyDefault(ReadGraph graph, Variable variable, GuidRVIPart part) throws DatabaseException {
  97                 Layer0 L0 = Layer0.getInstance(graph);
  98         for(Variable child : variable.getProperties(graph)) {
  99                 GUID id = child.getPossiblePropertyValue(graph, L0.identifier, GUID.BINDING);
 100                 if(id != null) {
 101                         if(id.mostSignificant == part.mostSignificant && id.leastSignificant == part.leastSignificant)
 102                                 return child;
 103                 }
 104         }
 105         throw new MissingVariableException("Could not resolve property " + part, variable.getPossibleRepresents(graph));
 106     }
 107
 108     @Override
 109     public Variable getVariable(ReadGraph graph, Variable context, RVIPart part) throws DatabaseException {
 110         if(part instanceof StringRVIPart) {
 111             StringRVIPart srp = (StringRVIPart)part;
 112             if(Role.CHILD.equals(srp.getRole())) return context.getChild(graph, srp.string);
 113             else if(Role.PROPERTY.equals(srp.getRole())) return context.getProperty(graph, srp.string);
 114         } else if(part instanceof ResourceRVIPart) {
 115             ResourceRVIPart rrp = (ResourceRVIPart)part;
 116             if(Role.CHILD.equals(rrp.getRole())) return resolveChild(graph, context, rrp.resource);
 117             else if(Role.PROPERTY.equals(rrp.getRole())) return resolveProperty(graph, context, rrp.resource);
 118         } else if(part instanceof GuidRVIPart) {
 119             GuidRVIPart grp = (GuidRVIPart)part;
 120             if(Role.CHILD.equals(grp.getRole())) return resolveChild(graph, context, grp);
 121             else if(Role.PROPERTY.equals(grp.getRole())) return resolveProperty(graph, context, grp);
 122         }
 123         throw new MissingVariableException("Unrecognized RVIPart: " + part, context.getPossibleRepresents(graph));
 124     }
 125
 126 }