X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=bundles%2Forg.simantics.objmap2%2Fsrc%2Forg%2Fsimantics%2Fobjmap%2Finternal%2FMonotoneBackwardMapping.java;fp=bundles%2Forg.simantics.objmap2%2Fsrc%2Forg%2Fsimantics%2Fobjmap%2Finternal%2FMonotoneBackwardMapping.java;h=8205d1f3f722c53ad66ef80d72ad8edfd322e9b6;hb=969bd23cab98a79ca9101af33334000879fb60c5;hp=0000000000000000000000000000000000000000;hpb=866dba5cd5a3929bbeae85991796acb212338a08;p=simantics%2Fplatform.git

diff --git a/bundles/org.simantics.objmap2/src/org/simantics/objmap/internal/MonotoneBackwardMapping.java b/bundles/org.simantics.objmap2/src/org/simantics/objmap/internal/MonotoneBackwardMapping.java
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+++ b/bundles/org.simantics.objmap2/src/org/simantics/objmap/internal/MonotoneBackwardMapping.java
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+/*******************************************************************************
+ * Copyright (c) 2012, 2013 Association for Decentralized Information Management in
+ * Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.objmap.internal;
+
+import gnu.trove.map.hash.THashMap;
+
+import java.util.Collections;
+import java.util.Set;
+
+import org.simantics.db.WriteGraph;
+import org.simantics.objmap.backward.IBackwardLinkType;
+import org.simantics.objmap.backward.IBackwardMapping;
+import org.simantics.objmap.backward.IBackwardMappingSchema;
+import org.simantics.objmap.exceptions.MappingException;
+
+/**
+ * An unidirectional (from range to domain) mapping that does not support removals.
+ * 
+ * @author Hannu Niemistö
+ */
+public class MonotoneBackwardMapping<Domain, Range> implements IBackwardMapping<Domain, Range> {
+
+    IBackwardMappingSchema<Domain, Range> schema;
+    THashMap<Range, Domain> map = new THashMap<Range, Domain>();
+    
+    public MonotoneBackwardMapping(IBackwardMappingSchema<Domain, Range> schema) {
+        this.schema = schema;
+    }
+
+    @Override
+    public Set<Range> getRange() {
+        return Collections.unmodifiableSet(map.keySet());
+    }
+
+    @Override
+    public Domain inverseGet(Range rangeElement) {
+        return map.get(rangeElement);
+    }
+
+    @Override
+    public Domain inverseMap(WriteGraph graph, Range rangeElement) throws MappingException {
+        Domain result = inverseGet(rangeElement);
+        if(result == null) {
+            IBackwardLinkType<Domain, Range> linkType = 
+                    schema.linkTypeOfRangeElement(graph, rangeElement);
+            // Two phase creation makes cyclic references possible
+            Domain domainElement = linkType.createDomainElement(graph, rangeElement);
+            map.put(rangeElement, domainElement);
+            linkType.createDomain(graph, this, domainElement, rangeElement);
+        }
+        return result;
+    }
+
+}