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

   1 package org.simantics.db.layer0.variable;
   2
   3 import org.simantics.db.ReadGraph;
   4 import org.simantics.db.exception.DatabaseException;
   5 import org.slf4j.Logger;
   6 import org.slf4j.LoggerFactory;
   7
   8 public class ProxyVariables {
   9
  10     private static final Logger LOGGER = LoggerFactory.getLogger(ProxyVariables.class);
  11
  12     public static Variable tryToOwn(ReadGraph graph, Variable parent, Variable variable) {
  13         if (variable instanceof ProxyVariableSupport) {
  14             ProxyVariableSupport pvs = (ProxyVariableSupport) variable;
  15             return pvs.attachTo(graph, parent);
  16         }
  17         return null;
  18     }
  19
  20     public static Variable tryToOwnRenamed(ReadGraph graph, Variable parent, Variable variable, String name) {
  21         if (variable instanceof ProxyVariableSupport) {
  22             ProxyVariableSupport pvs = (ProxyVariableSupport) variable;
  23             return pvs.attachToRenamed(graph, parent, name);
  24         }
  25         return null;
  26     }
  27
  28         public static Variable inputVariable(ReadGraph graph, Variable context) throws DatabaseException {
  29         Variable session = graph.syncRequest(new ProxySessionRequest(context));
  30         if(session == null) return null;
  31         String uri = session.getPossiblePropertyValue(graph, "inputURI");
  32         if(uri == null) {
  33                 // TODO HAXX - Please fix this
  34                 // we have no URI so this probably means that someone has inserted a non-session
  35                 // into the proxy variable => return that instead
  36                 return session;
  37         }
  38         return Variables.getVariable(graph, uri);
  39         }
  40
  41         public static Variable sessionVariable(ReadGraph graph, Variable self) throws DatabaseException {
  42                 return graph.syncRequest(new ProxySessionRequest(self));
  43         }
  44
  45         public static Variable makeProxyVariable(ReadGraph graph, Variable base, Variable input) throws DatabaseException {
  46
  47         base = base.getChild(graph, ProxyChildVariable.CONTEXT_BEGIN);
  48         String path = input.getURI(graph).substring("http:/".length());
  49         base = base.browse(graph, path);
  50         return base.getChild(graph, ProxyChildVariable.CONTEXT_END);
  51
  52         }
  53
  54     public static Variable proxySessionVariable(ReadGraph graph, Variable variable) throws DatabaseException {
  55
  56         try {
  57             return proxyVariableInput(graph, variable);
  58         } catch (Throwable t) {
  59             LOGGER.error("proxySessionVariable failed", t);
  60             return null;
  61         }
  62
  63     }
  64
  65     public static Variable proxyVariableBase(ReadGraph graph, Variable variable) throws DatabaseException {
  66
  67         try {
  68
  69                 Variable parent = variable.getParent(graph);
  70                 if(parent == null) return null;
  71
  72                 if(parent instanceof ProxyChildVariable) {
  73                         return ((ProxyChildVariable)parent).base();
  74                 } else {
  75                         return proxyVariableBase(graph, parent);
  76                 }
  77
  78         } catch (Throwable t) {
  79             LOGGER.error("proxyVariableBase failed", t);
  80             return null;
  81         }
  82
  83     }
  84
  85     public static Variable proxyVariableInput(ReadGraph graph, Variable variable) throws DatabaseException {
  86
  87                 if(variable instanceof ProxyChildVariable) {
  88                         Variable var = ((ProxyChildVariable)variable).other();
  89                         if(var.getParent(graph) == null) {
  90                                 return null;
  91                         }
  92                         return var;
  93                 } else {
  94                         Variable parent = variable.getParent(graph);
  95                         if(parent == null) return null;
  96                         else return proxyVariableInput(graph, parent);
  97                 }
  98
  99     }
 100
 101     public static Variable proxyVariableRoot(ReadGraph graph, Variable variable) throws DatabaseException {
 102
 103         try {
 104
 105                 Variable parent = variable.getParent(graph);
 106                 if(parent == null) return null;
 107
 108                 if(parent instanceof ProxyChildVariable) {
 109                         return variable;
 110                 } else {
 111                         return proxyVariableRoot(graph, parent);
 112                 }
 113
 114         } catch (Throwable t) {
 115             LOGGER.error("proxyVariableRoot failed", t);
 116             return null;
 117         }
 118
 119     }
 120
 121     public static boolean isProxy(ReadGraph graph, Variable variable) throws DatabaseException {
 122         return proxyVariableRoot(graph, variable) != null;
 123     }
 124
 125 }