Tossa reverse VariableAssignment

pom.xml

@@ -49,6 +49,11 @@
 		<artifactId>kryonet</artifactId>
 		<version>2.22.0-RC1</version>
 	</dependency>
+  	<dependency>
+  		<groupId>com.google.guava</groupId>
+  		<artifactId>guava</artifactId>
+  		<version>18.0</version>
+  	</dependency>
   </dependencies>
   
 </project>
\ No newline at end of file

src/de/tudarmstadt/maki/simonstrator/api/component/topology/VariableAssignment.java

@@ -2,6 +2,10 @@ package de.tudarmstadt.maki.simonstrator.api.component.topology;
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Set;
+
+import com.google.common.collect.BiMap;
+import com.google.common.collect.HashBiMap;
 
 import de.tudarmstadt.maki.simonstrator.api.common.UniqueID;
 import de.tudarmstadt.maki.simonstrator.api.common.graph.EdgeID;
@@ -13,11 +17,11 @@ import de.tudarmstadt.maki.simonstrator.api.common.graph.INodeID;
  */
 public final class VariableAssignment {
 
-	private final Map<INodeID, INodeID> nodeBinding;
+	private final BiMap<INodeID, INodeID> nodeBinding;
 	private final Map<EdgeID, EdgeID> linkBinding;
 
 	public VariableAssignment() {
-		this.nodeBinding = new HashMap<>();
+		this.nodeBinding = HashBiMap.create();
 		this.linkBinding = new HashMap<>();
 	}
 
@@ -31,10 +35,18 @@ public final class VariableAssignment {
 		return this.nodeBinding.get(variable);
 	}
 
+	public INodeID getInverseVariableBinding(final INodeID variable) {
+		return this.nodeBinding.inverse().get(variable);
+	}
+
 	public INodeID getNodeVariableBinding(final String key) {
 		return nodeBinding.get(INodeID.get(key));
 	}
 
+	public Set<Map.Entry<INodeID, INodeID>> getNodeBindingEntrySet() {
+		return nodeBinding.entrySet();
+	}
+
 	public void bindVariable(UniqueID variable, IElement candidate) {
 		if (variable instanceof INodeID) {
 			this.bindNodeVariable((INodeID) variable, (INodeID) candidate);
@@ -129,6 +141,4 @@ public final class VariableAssignment {
 				+ "]";
 	}
 
-
-
 }