Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.layer0.utils / src / org / simantics / layer0 / utils / binaryPredicates / CompositePredicate.java

diff --git a/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java
new file mode 100644 (file)
index 0000000..88000f6
--- /dev/null
+++ b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java
@@ -0,0 +1,162 @@
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ *     VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.layer0.utils.binaryPredicates;\r
+\r
+import java.util.Collection;\r
+import java.util.HashSet;\r
+import java.util.Set;\r
+\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.WriteGraph;\r
+import org.simantics.db.exception.DatabaseException;\r
+import org.simantics.utils.datastructures.Pair;\r
+\r
+public class CompositePredicate extends BinaryPredicate {\r
+       IBinaryPredicate first;\r
+       IBinaryPredicate second;\r
+       \r
+       int hasStatementDirection;\r
+       int getStatementsDirection;\r
+       \r
+       public CompositePredicate(IBinaryPredicate first, IBinaryPredicate second) {\r
+               this.first = first;\r
+               this.second = second;           \r
+               if(first.supportsGetStatements() && second.supportsGetObjects())\r
+                       getStatementsDirection = 1;\r
+               else if(second.supportsGetStatements() && first.supportsGetSubjects())\r
+                       getStatementsDirection = 2;\r
+               else\r
+                       this.getStatementsDirection = 0;\r
+               if(first.supportsGetObjects())\r
+                       hasStatementDirection = 1;\r
+               else if(second.supportsGetSubjects())\r
+                       hasStatementDirection = 2;\r
+               else\r
+                       throw new IllegalArgumentException("Cannot compose binary predicates such that the first one does not support getObjects and the second one does not support getSubjects.");\r
+       }\r
+\r
+       @Override\r
+       public Collection<Resource> getObjects(ReadGraph g, Resource subject) throws DatabaseException {\r
+               Set<Resource> result = new HashSet<Resource>();\r
+               for(Resource r : first.getObjects(g, subject))\r
+                       result.addAll(second.getObjects(g, r));\r
+               return result;\r
+       }\r
+\r
+       @Override\r
+       public Collection<Pair<Resource, Resource>> getStatements(ReadGraph g) throws DatabaseException {\r
+               Set<Pair<Resource, Resource>> result = \r
+                       new HashSet<Pair<Resource, Resource>>();\r
+               if(getStatementsDirection == 1)\r
+                       for(Pair<Resource, Resource> p : first.getStatements(g))\r
+                               for(Resource r : second.getObjects(g, p.second))\r
+                                       result.add(new Pair<Resource, Resource>(p.first, r));\r
+               else if(getStatementsDirection == 2)\r
+                       for(Pair<Resource, Resource> p : second.getStatements(g))\r
+                               for(Resource r : second.getSubjects(g, p.first))\r
+                                       result.add(new Pair<Resource, Resource>(r, p.second));\r
+               else\r
+                       throw new UnsupportedOperationException();\r
+               return result;\r
+       }\r
+\r
+       @Override\r
+       public Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {\r
+               Set<Resource> result = new HashSet<Resource>();\r
+               for(Resource r : second.getSubjects(g, object))\r
+                       result.addAll(first.getSubjects(g, r));\r
+               return result;\r
+       }\r
+\r
+       @Override\r
+       public boolean has(ReadGraph g, Resource subject, Resource object) throws DatabaseException {\r
+               if(hasStatementDirection == 1) {\r
+                       for(Resource r : first.getObjects(g, subject))\r
+                               if(second.has(g, r, object))\r
+                                       return true;\r
+               }\r
+               else {\r
+                       for(Resource r : second.getSubjects(g, object))\r
+                               if(second.has(g, subject, r))\r
+                                       return true;\r
+               }\r
+               return false;\r
+       }\r
+\r
+       @Override\r
+       public void add(WriteGraph g, Resource subject, Resource object) {\r
+               throw new UnsupportedOperationException();\r
+       }\r
+\r
+       @Override\r
+       public void remove(WriteGraph g, Resource subject, Resource object) {\r
+               throw new UnsupportedOperationException();\r
+       }\r
+\r
+       @Override\r
+       public boolean supportsAdditions() {\r
+               return false;\r
+       }\r
+\r
+       @Override\r
+       public boolean supportsGetObjects() {\r
+               return first.supportsGetObjects() && second.supportsGetObjects();\r
+       }\r
+\r
+       @Override\r
+       public boolean supportsGetStatements() {\r
+               return getStatementsDirection != 0;\r
+       }\r
+\r
+       @Override\r
+       public boolean supportsGetSubjects() {\r
+               return first.supportsGetSubjects() && second.supportsGetSubjects();\r
+       }\r
+\r
+       @Override\r
+       public boolean supportsRemovals() {             \r
+               return false;\r
+       }\r
+\r
+       @Override\r
+       public int hashCode() {\r
+               final int prime = 31;\r
+               int result = 1;\r
+               result = prime * result + ((first == null) ? 0 : first.hashCode());\r
+               result = prime * result + ((second == null) ? 0 : second.hashCode());\r
+               return result;\r
+       }\r
+\r
+       @Override\r
+       public boolean equals(Object obj) {\r
+               if (this == obj)\r
+                       return true;\r
+               if (obj == null)\r
+                       return false;\r
+               if (getClass() != obj.getClass())\r
+                       return false;\r
+               CompositePredicate other = (CompositePredicate) obj;\r
+               if (first == null) {\r
+                       if (other.first != null)\r
+                               return false;\r
+               } else if (!first.equals(other.first))\r
+                       return false;\r
+               if (second == null) {\r
+                       if (other.second != null)\r
+                               return false;\r
+               } else if (!second.equals(other.second))\r
+                       return false;\r
+               return true;\r
+       }       \r
+       \r
+}\r