X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=bundles%2Forg.simantics.db.layer0%2Fsrc%2Forg%2Fsimantics%2Fdb%2Flayer0%2Frequest%2Fcombinations%2FCombinators.java;fp=bundles%2Forg.simantics.db.layer0%2Fsrc%2Forg%2Fsimantics%2Fdb%2Flayer0%2Frequest%2Fcombinations%2FCombinators.java;h=bd2409f5d9b2eecde6a5f369562a141365938adb;hb=0ae2b770234dfc3cbb18bd38f324125cf0faca07;hp=2fc619ec7cb1fb744065f70d352aa0a3d7bb0694;hpb=24e2b34260f219f0d1644ca7a138894980e25b14;p=simantics%2Fplatform.git

diff --git a/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/request/combinations/Combinators.java b/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/request/combinations/Combinators.java
index 2fc619ec7..bd2409f5d 100644
--- a/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/request/combinations/Combinators.java
+++ b/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/request/combinations/Combinators.java
@@ -1,684 +1,684 @@
-/*******************************************************************************
- * Copyright (c) 2007, 2010 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.db.layer0.request.combinations;
-
-import java.util.HashMap;
-import java.util.Map;
-
-import org.simantics.db.ReadGraph;
-import org.simantics.db.Resource;
-import org.simantics.db.common.request.ParametrizedRead;
-import org.simantics.db.exception.DatabaseException;
-import org.simantics.db.procedure.AsyncMultiProcedure;
-import org.simantics.db.procedure.Procedure;
-import org.simantics.db.request.MultiRead;
-import org.simantics.db.request.Read;
-import org.simantics.layer0.Layer0;
-
-/**
- * Functions that create new read requests by combining simpler ones.
- * @author Hannu Niemist�
- */
-public class Combinators {	
-		
-	// ------------------------------------------------------------------------
-	
-	private static class Objects implements MultiRead<Resource> {
-		Resource subject;		
-		Resource relation;
-		public Objects(Resource subject, Resource relation) {
-			this.subject = subject;
-			this.relation = relation;
-		}
-		@Override
-		public void perform(ReadGraph graph,
-				AsyncMultiProcedure<Resource> callback)
-				throws DatabaseException {
-			graph.forEachObject(subject, relation, callback);
-		}		
-	    @Override
-	    public int hashCode() {
-	        return subject.hashCode() + 31 * relation.hashCode();
-	    }
-	    @Override
-	    public boolean equals(Object object) {
-	        if (this == object) return true;
-	        else if (object == null || getClass() != object.getClass()) return false;
-	        Objects other = (Objects)object;
-	        return subject.equals(other.subject) && relation.equals(other.relation);
-	    }
-	}
-	
-	/**
-	 * Returns a multi read request that reads the objects of given subject and relation. 
-	 */
-	public static MultiRead<Resource> objects(Resource subject, Resource relation) {
-		return new Objects(subject, relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Relation implements ParametrizedMultiRead<Resource, Resource> {
-		Resource relation;
-		public Relation(Resource relation) {
-			this.relation = relation;
-		}
-		@Override
-		public MultiRead<Resource> get(Resource subject) {
-			return objects(subject, relation);
-		}
-	    @Override
-	    public int hashCode() {
-	        return getClass().hashCode() + 31 * relation.hashCode();
-	    }
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Relation other = (Relation)obj;
-			return relation.equals(other.relation);
-		}
-	}
-	
-	/**
-	 * Returns a function <code>subject -> objects(subject, relation)</code>. 
-	 */
-	public static ParametrizedMultiRead<Resource,Resource> relation(Resource relation) {
-		return new Relation(relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	public static class SynchronizationProcedure<T> implements Procedure<T> {
-		T result;
-		DatabaseException exception;
-		boolean ready = false;
-		@Override
-		public synchronized void exception(Throwable t) {
-			this.exception = 
-				t instanceof DatabaseException ? (DatabaseException)t : new DatabaseException(t);
-			ready = true;
-			notify();
-		}
-		@Override
-		public synchronized void execute(T result) {
-			this.result = result;
-			ready = true;		
-			notify();
-		}		
-		public synchronized T getResult() throws DatabaseException {
-			if(!ready) {
-				try {
-					wait();
-				} catch (InterruptedException e) {
-					throw new DatabaseException(e);
-				}	
-			}
-			if(exception != null)
-				throw exception;
-			return result;
-		}
-	}
-	
-	private static class PossibleObject implements Read<Resource> {
-		Resource subject;		
-		Resource relation;
-		public PossibleObject(Resource subject, Resource relation) {
-			this.subject = subject;
-			this.relation = relation;
-		}
-		@Override
-		public Resource perform(ReadGraph graph) throws DatabaseException {
-			SynchronizationProcedure<Resource> procedure = new SynchronizationProcedure<Resource>();
-			graph.forPossibleObject(subject, relation, procedure);
-			return procedure.getResult();
-		}	
-	    @Override
-	    public int hashCode() {
-	        return subject.hashCode() + 31 * relation.hashCode();
-	    }
-	    @Override
-	    public boolean equals(Object object) {
-	        if (this == object) return true;
-	        else if (object == null || getClass() != object.getClass()) return false;
-	        PossibleObject other = (PossibleObject)object;
-	        return subject.equals(other.subject) && relation.equals(other.relation);
-	    }
-	}
-	
-	/**
-	 * Returns a read request that reads an object possibly connected to the subject by the relation.
-	 */
-	public static Read<Resource> possibleObject(Resource subject, Resource relation) {
-		return new PossibleObject(subject, relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class PartialFunction implements ParametrizedRead<Resource, Resource> {
-		Resource relation;
-		public PartialFunction(Resource relation) {
-			this.relation = relation;
-		}
-		@Override
-		public Read<Resource> get(Resource subject) {
-			return possibleObject(subject, relation);
-		}
-	    @Override
-	    public int hashCode() {
-	        return getClass().hashCode() + 31 * relation.hashCode();
-	    }
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			PartialFunction other = (PartialFunction)obj;
-			return relation.equals(other.relation);
-		}
-	}
-	
-	/**
-	 * Returns a function <code>subject -> possibleObject(subject, relation)</code>. 
-	 */
-	public static ParametrizedRead<Resource,Resource> partialFunction(Resource relation) {
-		return new PartialFunction(relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class SingleObject implements Read<Resource> {
-		Resource subject;		
-		Resource relation;
-		public SingleObject(Resource subject, Resource relation) {
-			this.subject = subject;
-			this.relation = relation;
-		}
-		@Override
-		public Resource perform(ReadGraph graph) throws DatabaseException {
-			SynchronizationProcedure<Resource> procedure = new SynchronizationProcedure<Resource>();
-			graph.forSingleObject(subject, relation, procedure);
-			return procedure.getResult();
-		}	
-	    @Override
-	    public int hashCode() {
-	        return subject.hashCode() + 31 * relation.hashCode();
-	    }
-	    @Override
-	    public boolean equals(Object object) {
-	        if (this == object) return true;
-	        else if (object == null || getClass() != object.getClass()) return false;
-	        SingleObject other = (SingleObject)object;
-	        return subject.equals(other.subject) && relation.equals(other.relation);
-	    }
-	}
-	
-	/**
-	 * Returns a read request that reads an object connected to the subject by the relation.
-	 */
-	public static Read<Resource> singleObject(Resource subject, Resource relation) {
-		return new SingleObject(subject, relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class CompleteFunction implements ParametrizedRead<Resource, Resource> {
-		Resource relation;
-		public CompleteFunction(Resource relation) {
-			this.relation = relation;
-		}
-		@Override
-		public Read<Resource> get(Resource subject) {
-			return singleObject(subject, relation);
-		}
-	    @Override
-	    public int hashCode() {
-	        return getClass().hashCode() + 31 * relation.hashCode();
-	    }
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			CompleteFunction other = (CompleteFunction)obj;
-			return relation.equals(other.relation);
-		}
-	}
-	
-	/**
-	 * Returns a function <code>subject -> singleObject(subject, relation)</code>. 
-	 */
-	public static ParametrizedRead<Resource,Resource> completeFunction(Resource relation) {
-		return new CompleteFunction(relation);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Compose1<X, Y> implements Read<Y> {
-		final ParametrizedRead<X, Y> f;
-		final Read<X> g;		
-		public Compose1(ParametrizedRead<X, Y> f, Read<X> g) {
-			this.f = f;
-			this.g = g;
-		}
-		@Override
-		public Y perform(ReadGraph graph) throws DatabaseException {
-			return graph.syncRequest(f.get(graph.syncRequest(g)));
-		}		
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose1<?, ?> other = (Compose1<?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y> Read<Y> compose(ParametrizedRead<X, Y> f, Read<X> g) {
-		return new Compose1<X, Y>(f, g);
-	}
-
-	// ------------------------------------------------------------------------
-	
-	private static class Compose2<X, Y, Z> implements ParametrizedRead<X, Z> {
-		final ParametrizedRead<Y, Z> f;
-		final ParametrizedRead<X, Y> g;		
-		public Compose2(ParametrizedRead<Y, Z> f, ParametrizedRead<X, Y> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public Read<Z> get(X x) {
-			return compose(f, g.get(x));
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose2<?, ?, ?> other = (Compose2<?, ?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y, Z> ParametrizedRead<X, Z> compose(ParametrizedRead<Y, Z> f, ParametrizedRead<X, Y> g) {
-		return new Compose2<X, Y, Z>(f, g);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Compose3<X, Y> implements MultiRead<Y> {
-		final ParametrizedRead<X, Y> f;
-		final MultiRead<X> g;		
-		public Compose3(ParametrizedRead<X, Y> f, MultiRead<X> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public void perform(ReadGraph graph, final AsyncMultiProcedure<Y> callback)	throws DatabaseException {
-		    try {
-				for(X x : graph.syncRequest(g))
-					callback.execute(graph, graph.syncRequest(f.get(x)));
-				callback.finished(graph);
-			} catch(DatabaseException e) {
-				callback.exception(graph, e);
-			}
-			/*// Not sure if this is correct
-		   graph.syncRequest(g, new SyncMultiProcedure<X>() {
-				@Override
-				public void exception(ReadGraph graph, Throwable throwable)
-				throws DatabaseException {
-					callback.exception(graph, throwable);					
-				}
-				@Override
-				public void execute(ReadGraph graph, X x)
-				throws DatabaseException {
-					callback.execute(graph, graph.syncRequest(f.get(x)));
-				}
-				@Override
-				public void finished(ReadGraph graph)
-				throws DatabaseException {
-				}
-			});
-			callback.finished(graph);*/
-		}					
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose3<?, ?> other = (Compose3<?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y> MultiRead<Y> compose(ParametrizedRead<X, Y> f, MultiRead<X> g) {
-		return new Compose3<X, Y>(f, g);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Compose4<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
-		final ParametrizedRead<Y, Z> f;
-		final ParametrizedMultiRead<X, Y> g;		
-		public Compose4(ParametrizedRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public MultiRead<Z> get(X x) {
-			return compose(f, g.get(x));
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose4<?, ?, ?> other = (Compose4<?, ?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
-		return new Compose4<X, Y, Z>(f, g);
-	}
-
-	// ------------------------------------------------------------------------
-	
-	private static class Compose5<X, Y> implements MultiRead<Y> {
-		final ParametrizedMultiRead<X, Y> f;
-		final Read<X> g;		
-		public Compose5(ParametrizedMultiRead<X, Y> f, Read<X> g) {
-			this.f = f;
-			this.g = g;
-		}
-		@Override
-		public void perform(ReadGraph graph, AsyncMultiProcedure<Y> callback)
-				throws DatabaseException {
-			graph.syncRequest(f.get(graph.syncRequest(g)), callback);
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose5<?, ?> other = (Compose5<?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y> MultiRead<Y> compose(ParametrizedMultiRead<X, Y> f, Read<X> g) {
-		return new Compose5<X, Y>(f, g);
-	}
-
-	// ------------------------------------------------------------------------
-	
-	private static class Compose6<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
-		final ParametrizedMultiRead<Y, Z> f;
-		final ParametrizedRead<X, Y> g;		
-		public Compose6(ParametrizedMultiRead<Y, Z> f, ParametrizedRead<X, Y> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public MultiRead<Z> get(X x) {
-			return compose(f, g.get(x));
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose6<?, ?, ?> other = (Compose6<?, ?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedMultiRead<Y, Z> f, ParametrizedRead<X, Y> g) {
-		return new Compose6<X, Y, Z>(f, g);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Compose7<X, Y> implements MultiRead<Y> {
-		final ParametrizedMultiRead<X, Y> f;
-		final MultiRead<X> g;		
-		public Compose7(ParametrizedMultiRead<X, Y> f, MultiRead<X> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public void perform(ReadGraph graph, final AsyncMultiProcedure<Y> callback)	throws DatabaseException {
-		    try {
-				for(X x : graph.syncRequest(g))
-					for(Y y : graph.syncRequest(f.get(x)))
-						callback.execute(graph, y);
-				callback.finished(graph);
-			} catch(DatabaseException e) {
-				callback.exception(graph, e);
-			}
-			/*// Not correct because inner syncRequest calls callback.finished 
-		    graph.syncRequest(g, new SyncMultiProcedure<X>() {
-				@Override
-				public void exception(ReadGraph graph, Throwable throwable)
-				throws DatabaseException {
-					callback.exception(graph, throwable);					
-				}
-				@Override
-				public void execute(ReadGraph graph, X x) throws DatabaseException {
-					graph.syncRequest(f.get(x), callback);
-				}
-				@Override
-				public void finished(ReadGraph graph)
-				throws DatabaseException {
-				}
-			});
-			callback.finished(graph);
-			*/
-		}					
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose7<?, ?> other = (Compose7<?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y> MultiRead<Y> compose(ParametrizedMultiRead<X, Y> f, MultiRead<X> g) {
-		return new Compose7<X, Y>(f, g);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Compose8<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
-		final ParametrizedMultiRead<Y, Z> f;
-		final ParametrizedMultiRead<X, Y> g;		
-		public Compose8(ParametrizedMultiRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
-			this.f = f;
-			this.g = g;
-		}
-		public MultiRead<Z> get(X x) {
-			return compose(f, g.get(x));
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Compose8<?, ?, ?> other = (Compose8<?, ?, ?>)obj;
-			return f.equals(other.f) && g.equals(other.g);
-		}
-	}
-	
-	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedMultiRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
-		return new Compose8<X, Y, Z>(f, g);
-	}	
-	
-	// ------------------------------------------------------------------------
-
-	private static class Index<K, V> implements Read<Map<K, V>> {
-		final MultiRead<V> values;
-		final ParametrizedRead<V, K> keyOfValue;
-		public Index(MultiRead<V> values, ParametrizedRead<V, K> keyOfValue) {
-			this.values = values;
-			this.keyOfValue = keyOfValue;
-		}
-		@Override
-		public Map<K, V> perform(ReadGraph graph) throws DatabaseException {
-			HashMap<K, V> result = new HashMap<K, V>();
-			for(V value : graph.syncRequest(values))
-				result.put(graph.syncRequest(keyOfValue.get(value)), value);
-			return result;
-		}
-		@Override
-		public int hashCode() {
-			return getClass().hashCode() + 31 * (values.hashCode() + 31 * keyOfValue.hashCode());
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Index<?, ?> other = (Index<?, ?>)obj;
-			return values.equals(other.values) && keyOfValue.equals(other.keyOfValue);
-		}	
-	}
-	
-	public static <K, V> Read<Map<K, V>> index(MultiRead<V> values, ParametrizedRead<V, K> keyOfValue) {
-		return new Index<K, V>(values, keyOfValue);
-	}
-	
-	// ------------------------------------------------------------------------
-
-	private static class Constant<T> implements Read<T> {
-		T value;
-		public Constant(T value) {
-			this.value = value;
-		}
-		@Override
-		public T perform(ReadGraph graph) throws DatabaseException {
-			return value;
-		}
-		@Override
-		public int hashCode() {
-			return value == null ? 0 : value.hashCode();
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if (this == obj)
-				return true;
-			if (obj == null || getClass() != obj.getClass())
-				return false;
-			Constant<?> other = (Constant<?>) obj;
-			return value == null ? other.value == null : value.equals(other.value);
-		}		
-	}
-	
-	public static <T> Read<T> constant(T value) {
-		return new Constant<T>(value);
-	}
-	
-	// ------------------------------------------------------------------------
-
-	private static class Singleton<T> implements MultiRead<T> {
-		T value;
-		public Singleton(T value) {
-			this.value = value;
-		}
-		@Override
-		public void perform(ReadGraph graph, AsyncMultiProcedure<T> callback)
-				throws DatabaseException {
-			callback.execute(graph, value);
-			callback.finished(graph);
-		}
-		@Override
-		public int hashCode() {
-			return value.hashCode();
-		}
-		@Override
-		public boolean equals(Object obj) {
-			if (this == obj)
-				return true;
-			if (obj == null || getClass() != obj.getClass())
-				return false;
-			Singleton<?> other = (Singleton<?>) obj;
-			return value.equals(other.value);
-		}	
-	}
-	
-	public static <T> MultiRead<T> singleton(T value) {
-		return new Singleton<T>(value);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	private static class Name implements Read<String> {
-		Resource resource;
-		public Name(Resource resource) {
-			this.resource = resource;
-		}
-		@Override
-		public String perform(ReadGraph graph) throws DatabaseException {
-	    	Layer0 L0 = Layer0.getInstance(graph);
-			SynchronizationProcedure<String> procedure = new SynchronizationProcedure<String>();
-			graph.forRelatedValue(resource, L0.HasName, procedure);
-			return procedure.getResult();
-		}
-	    @Override
-	    public int hashCode() {
-	        return getClass().hashCode() + 31 * resource.hashCode();
-	    }
-		@Override
-		public boolean equals(Object obj) {
-			if(obj == this) return true;
-			if(obj == null || obj.getClass() != getClass())	return false;
-			Name other = (Name)obj;
-			return resource.equals(other.resource);
-		}		
-	}	
-	public static Read<String> name(Resource resource) {
-		return new Name(resource);
-	}
-	
-	// ------------------------------------------------------------------------
-	
-	public static final ParametrizedRead<Resource, String> NAME = new ParametrizedRead<Resource, String>() {
-
-		@Override
-		public Read<String> get(Resource resource) {
-			return name(resource);
-		}
-		
-	};
-	
-	// ------------------------------------------------------------------------
-	
-}
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 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.db.layer0.request.combinations;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.simantics.db.ReadGraph;
+import org.simantics.db.Resource;
+import org.simantics.db.common.request.ParametrizedRead;
+import org.simantics.db.exception.DatabaseException;
+import org.simantics.db.procedure.AsyncMultiProcedure;
+import org.simantics.db.procedure.Procedure;
+import org.simantics.db.request.MultiRead;
+import org.simantics.db.request.Read;
+import org.simantics.layer0.Layer0;
+
+/**
+ * Functions that create new read requests by combining simpler ones.
+ * @author Hannu Niemist�
+ */
+public class Combinators {	
+		
+	// ------------------------------------------------------------------------
+	
+	private static class Objects implements MultiRead<Resource> {
+		Resource subject;		
+		Resource relation;
+		public Objects(Resource subject, Resource relation) {
+			this.subject = subject;
+			this.relation = relation;
+		}
+		@Override
+		public void perform(ReadGraph graph,
+				AsyncMultiProcedure<Resource> callback)
+				throws DatabaseException {
+			graph.forEachObject(subject, relation, callback);
+		}		
+	    @Override
+	    public int hashCode() {
+	        return subject.hashCode() + 31 * relation.hashCode();
+	    }
+	    @Override
+	    public boolean equals(Object object) {
+	        if (this == object) return true;
+	        else if (object == null || getClass() != object.getClass()) return false;
+	        Objects other = (Objects)object;
+	        return subject.equals(other.subject) && relation.equals(other.relation);
+	    }
+	}
+	
+	/**
+	 * Returns a multi read request that reads the objects of given subject and relation. 
+	 */
+	public static MultiRead<Resource> objects(Resource subject, Resource relation) {
+		return new Objects(subject, relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Relation implements ParametrizedMultiRead<Resource, Resource> {
+		Resource relation;
+		public Relation(Resource relation) {
+			this.relation = relation;
+		}
+		@Override
+		public MultiRead<Resource> get(Resource subject) {
+			return objects(subject, relation);
+		}
+	    @Override
+	    public int hashCode() {
+	        return getClass().hashCode() + 31 * relation.hashCode();
+	    }
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Relation other = (Relation)obj;
+			return relation.equals(other.relation);
+		}
+	}
+	
+	/**
+	 * Returns a function <code>subject -> objects(subject, relation)</code>. 
+	 */
+	public static ParametrizedMultiRead<Resource,Resource> relation(Resource relation) {
+		return new Relation(relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	public static class SynchronizationProcedure<T> implements Procedure<T> {
+		T result;
+		DatabaseException exception;
+		boolean ready = false;
+		@Override
+		public synchronized void exception(Throwable t) {
+			this.exception = 
+				t instanceof DatabaseException ? (DatabaseException)t : new DatabaseException(t);
+			ready = true;
+			notify();
+		}
+		@Override
+		public synchronized void execute(T result) {
+			this.result = result;
+			ready = true;		
+			notify();
+		}		
+		public synchronized T getResult() throws DatabaseException {
+			if(!ready) {
+				try {
+					wait();
+				} catch (InterruptedException e) {
+					throw new DatabaseException(e);
+				}	
+			}
+			if(exception != null)
+				throw exception;
+			return result;
+		}
+	}
+	
+	private static class PossibleObject implements Read<Resource> {
+		Resource subject;		
+		Resource relation;
+		public PossibleObject(Resource subject, Resource relation) {
+			this.subject = subject;
+			this.relation = relation;
+		}
+		@Override
+		public Resource perform(ReadGraph graph) throws DatabaseException {
+			SynchronizationProcedure<Resource> procedure = new SynchronizationProcedure<Resource>();
+			graph.forPossibleObject(subject, relation, procedure);
+			return procedure.getResult();
+		}	
+	    @Override
+	    public int hashCode() {
+	        return subject.hashCode() + 31 * relation.hashCode();
+	    }
+	    @Override
+	    public boolean equals(Object object) {
+	        if (this == object) return true;
+	        else if (object == null || getClass() != object.getClass()) return false;
+	        PossibleObject other = (PossibleObject)object;
+	        return subject.equals(other.subject) && relation.equals(other.relation);
+	    }
+	}
+	
+	/**
+	 * Returns a read request that reads an object possibly connected to the subject by the relation.
+	 */
+	public static Read<Resource> possibleObject(Resource subject, Resource relation) {
+		return new PossibleObject(subject, relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class PartialFunction implements ParametrizedRead<Resource, Resource> {
+		Resource relation;
+		public PartialFunction(Resource relation) {
+			this.relation = relation;
+		}
+		@Override
+		public Read<Resource> get(Resource subject) {
+			return possibleObject(subject, relation);
+		}
+	    @Override
+	    public int hashCode() {
+	        return getClass().hashCode() + 31 * relation.hashCode();
+	    }
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			PartialFunction other = (PartialFunction)obj;
+			return relation.equals(other.relation);
+		}
+	}
+	
+	/**
+	 * Returns a function <code>subject -> possibleObject(subject, relation)</code>. 
+	 */
+	public static ParametrizedRead<Resource,Resource> partialFunction(Resource relation) {
+		return new PartialFunction(relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class SingleObject implements Read<Resource> {
+		Resource subject;		
+		Resource relation;
+		public SingleObject(Resource subject, Resource relation) {
+			this.subject = subject;
+			this.relation = relation;
+		}
+		@Override
+		public Resource perform(ReadGraph graph) throws DatabaseException {
+			SynchronizationProcedure<Resource> procedure = new SynchronizationProcedure<Resource>();
+			graph.forSingleObject(subject, relation, procedure);
+			return procedure.getResult();
+		}	
+	    @Override
+	    public int hashCode() {
+	        return subject.hashCode() + 31 * relation.hashCode();
+	    }
+	    @Override
+	    public boolean equals(Object object) {
+	        if (this == object) return true;
+	        else if (object == null || getClass() != object.getClass()) return false;
+	        SingleObject other = (SingleObject)object;
+	        return subject.equals(other.subject) && relation.equals(other.relation);
+	    }
+	}
+	
+	/**
+	 * Returns a read request that reads an object connected to the subject by the relation.
+	 */
+	public static Read<Resource> singleObject(Resource subject, Resource relation) {
+		return new SingleObject(subject, relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class CompleteFunction implements ParametrizedRead<Resource, Resource> {
+		Resource relation;
+		public CompleteFunction(Resource relation) {
+			this.relation = relation;
+		}
+		@Override
+		public Read<Resource> get(Resource subject) {
+			return singleObject(subject, relation);
+		}
+	    @Override
+	    public int hashCode() {
+	        return getClass().hashCode() + 31 * relation.hashCode();
+	    }
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			CompleteFunction other = (CompleteFunction)obj;
+			return relation.equals(other.relation);
+		}
+	}
+	
+	/**
+	 * Returns a function <code>subject -> singleObject(subject, relation)</code>. 
+	 */
+	public static ParametrizedRead<Resource,Resource> completeFunction(Resource relation) {
+		return new CompleteFunction(relation);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Compose1<X, Y> implements Read<Y> {
+		final ParametrizedRead<X, Y> f;
+		final Read<X> g;		
+		public Compose1(ParametrizedRead<X, Y> f, Read<X> g) {
+			this.f = f;
+			this.g = g;
+		}
+		@Override
+		public Y perform(ReadGraph graph) throws DatabaseException {
+			return graph.syncRequest(f.get(graph.syncRequest(g)));
+		}		
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose1<?, ?> other = (Compose1<?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y> Read<Y> compose(ParametrizedRead<X, Y> f, Read<X> g) {
+		return new Compose1<X, Y>(f, g);
+	}
+
+	// ------------------------------------------------------------------------
+	
+	private static class Compose2<X, Y, Z> implements ParametrizedRead<X, Z> {
+		final ParametrizedRead<Y, Z> f;
+		final ParametrizedRead<X, Y> g;		
+		public Compose2(ParametrizedRead<Y, Z> f, ParametrizedRead<X, Y> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public Read<Z> get(X x) {
+			return compose(f, g.get(x));
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose2<?, ?, ?> other = (Compose2<?, ?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y, Z> ParametrizedRead<X, Z> compose(ParametrizedRead<Y, Z> f, ParametrizedRead<X, Y> g) {
+		return new Compose2<X, Y, Z>(f, g);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Compose3<X, Y> implements MultiRead<Y> {
+		final ParametrizedRead<X, Y> f;
+		final MultiRead<X> g;		
+		public Compose3(ParametrizedRead<X, Y> f, MultiRead<X> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public void perform(ReadGraph graph, final AsyncMultiProcedure<Y> callback)	throws DatabaseException {
+		    try {
+				for(X x : graph.syncRequest(g))
+					callback.execute(graph, graph.syncRequest(f.get(x)));
+				callback.finished(graph);
+			} catch(DatabaseException e) {
+				callback.exception(graph, e);
+			}
+			/*// Not sure if this is correct
+		   graph.syncRequest(g, new SyncMultiProcedure<X>() {
+				@Override
+				public void exception(ReadGraph graph, Throwable throwable)
+				throws DatabaseException {
+					callback.exception(graph, throwable);					
+				}
+				@Override
+				public void execute(ReadGraph graph, X x)
+				throws DatabaseException {
+					callback.execute(graph, graph.syncRequest(f.get(x)));
+				}
+				@Override
+				public void finished(ReadGraph graph)
+				throws DatabaseException {
+				}
+			});
+			callback.finished(graph);*/
+		}					
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose3<?, ?> other = (Compose3<?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y> MultiRead<Y> compose(ParametrizedRead<X, Y> f, MultiRead<X> g) {
+		return new Compose3<X, Y>(f, g);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Compose4<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
+		final ParametrizedRead<Y, Z> f;
+		final ParametrizedMultiRead<X, Y> g;		
+		public Compose4(ParametrizedRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public MultiRead<Z> get(X x) {
+			return compose(f, g.get(x));
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose4<?, ?, ?> other = (Compose4<?, ?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
+		return new Compose4<X, Y, Z>(f, g);
+	}
+
+	// ------------------------------------------------------------------------
+	
+	private static class Compose5<X, Y> implements MultiRead<Y> {
+		final ParametrizedMultiRead<X, Y> f;
+		final Read<X> g;		
+		public Compose5(ParametrizedMultiRead<X, Y> f, Read<X> g) {
+			this.f = f;
+			this.g = g;
+		}
+		@Override
+		public void perform(ReadGraph graph, AsyncMultiProcedure<Y> callback)
+				throws DatabaseException {
+			graph.syncRequest(f.get(graph.syncRequest(g)), callback);
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose5<?, ?> other = (Compose5<?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y> MultiRead<Y> compose(ParametrizedMultiRead<X, Y> f, Read<X> g) {
+		return new Compose5<X, Y>(f, g);
+	}
+
+	// ------------------------------------------------------------------------
+	
+	private static class Compose6<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
+		final ParametrizedMultiRead<Y, Z> f;
+		final ParametrizedRead<X, Y> g;		
+		public Compose6(ParametrizedMultiRead<Y, Z> f, ParametrizedRead<X, Y> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public MultiRead<Z> get(X x) {
+			return compose(f, g.get(x));
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose6<?, ?, ?> other = (Compose6<?, ?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedMultiRead<Y, Z> f, ParametrizedRead<X, Y> g) {
+		return new Compose6<X, Y, Z>(f, g);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Compose7<X, Y> implements MultiRead<Y> {
+		final ParametrizedMultiRead<X, Y> f;
+		final MultiRead<X> g;		
+		public Compose7(ParametrizedMultiRead<X, Y> f, MultiRead<X> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public void perform(ReadGraph graph, final AsyncMultiProcedure<Y> callback)	throws DatabaseException {
+		    try {
+				for(X x : graph.syncRequest(g))
+					for(Y y : graph.syncRequest(f.get(x)))
+						callback.execute(graph, y);
+				callback.finished(graph);
+			} catch(DatabaseException e) {
+				callback.exception(graph, e);
+			}
+			/*// Not correct because inner syncRequest calls callback.finished 
+		    graph.syncRequest(g, new SyncMultiProcedure<X>() {
+				@Override
+				public void exception(ReadGraph graph, Throwable throwable)
+				throws DatabaseException {
+					callback.exception(graph, throwable);					
+				}
+				@Override
+				public void execute(ReadGraph graph, X x) throws DatabaseException {
+					graph.syncRequest(f.get(x), callback);
+				}
+				@Override
+				public void finished(ReadGraph graph)
+				throws DatabaseException {
+				}
+			});
+			callback.finished(graph);
+			*/
+		}					
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose7<?, ?> other = (Compose7<?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y> MultiRead<Y> compose(ParametrizedMultiRead<X, Y> f, MultiRead<X> g) {
+		return new Compose7<X, Y>(f, g);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Compose8<X, Y, Z> implements ParametrizedMultiRead<X, Z> {
+		final ParametrizedMultiRead<Y, Z> f;
+		final ParametrizedMultiRead<X, Y> g;		
+		public Compose8(ParametrizedMultiRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
+			this.f = f;
+			this.g = g;
+		}
+		public MultiRead<Z> get(X x) {
+			return compose(f, g.get(x));
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (f.hashCode() + 31 * g.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Compose8<?, ?, ?> other = (Compose8<?, ?, ?>)obj;
+			return f.equals(other.f) && g.equals(other.g);
+		}
+	}
+	
+	public static <X, Y, Z> ParametrizedMultiRead<X, Z> compose(ParametrizedMultiRead<Y, Z> f, ParametrizedMultiRead<X, Y> g) {
+		return new Compose8<X, Y, Z>(f, g);
+	}	
+	
+	// ------------------------------------------------------------------------
+
+	private static class Index<K, V> implements Read<Map<K, V>> {
+		final MultiRead<V> values;
+		final ParametrizedRead<V, K> keyOfValue;
+		public Index(MultiRead<V> values, ParametrizedRead<V, K> keyOfValue) {
+			this.values = values;
+			this.keyOfValue = keyOfValue;
+		}
+		@Override
+		public Map<K, V> perform(ReadGraph graph) throws DatabaseException {
+			HashMap<K, V> result = new HashMap<K, V>();
+			for(V value : graph.syncRequest(values))
+				result.put(graph.syncRequest(keyOfValue.get(value)), value);
+			return result;
+		}
+		@Override
+		public int hashCode() {
+			return getClass().hashCode() + 31 * (values.hashCode() + 31 * keyOfValue.hashCode());
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Index<?, ?> other = (Index<?, ?>)obj;
+			return values.equals(other.values) && keyOfValue.equals(other.keyOfValue);
+		}	
+	}
+	
+	public static <K, V> Read<Map<K, V>> index(MultiRead<V> values, ParametrizedRead<V, K> keyOfValue) {
+		return new Index<K, V>(values, keyOfValue);
+	}
+	
+	// ------------------------------------------------------------------------
+
+	private static class Constant<T> implements Read<T> {
+		T value;
+		public Constant(T value) {
+			this.value = value;
+		}
+		@Override
+		public T perform(ReadGraph graph) throws DatabaseException {
+			return value;
+		}
+		@Override
+		public int hashCode() {
+			return value == null ? 0 : value.hashCode();
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (obj == null || getClass() != obj.getClass())
+				return false;
+			Constant<?> other = (Constant<?>) obj;
+			return value == null ? other.value == null : value.equals(other.value);
+		}		
+	}
+	
+	public static <T> Read<T> constant(T value) {
+		return new Constant<T>(value);
+	}
+	
+	// ------------------------------------------------------------------------
+
+	private static class Singleton<T> implements MultiRead<T> {
+		T value;
+		public Singleton(T value) {
+			this.value = value;
+		}
+		@Override
+		public void perform(ReadGraph graph, AsyncMultiProcedure<T> callback)
+				throws DatabaseException {
+			callback.execute(graph, value);
+			callback.finished(graph);
+		}
+		@Override
+		public int hashCode() {
+			return value.hashCode();
+		}
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (obj == null || getClass() != obj.getClass())
+				return false;
+			Singleton<?> other = (Singleton<?>) obj;
+			return value.equals(other.value);
+		}	
+	}
+	
+	public static <T> MultiRead<T> singleton(T value) {
+		return new Singleton<T>(value);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	private static class Name implements Read<String> {
+		Resource resource;
+		public Name(Resource resource) {
+			this.resource = resource;
+		}
+		@Override
+		public String perform(ReadGraph graph) throws DatabaseException {
+	    	Layer0 L0 = Layer0.getInstance(graph);
+			SynchronizationProcedure<String> procedure = new SynchronizationProcedure<String>();
+			graph.forRelatedValue(resource, L0.HasName, procedure);
+			return procedure.getResult();
+		}
+	    @Override
+	    public int hashCode() {
+	        return getClass().hashCode() + 31 * resource.hashCode();
+	    }
+		@Override
+		public boolean equals(Object obj) {
+			if(obj == this) return true;
+			if(obj == null || obj.getClass() != getClass())	return false;
+			Name other = (Name)obj;
+			return resource.equals(other.resource);
+		}		
+	}	
+	public static Read<String> name(Resource resource) {
+		return new Name(resource);
+	}
+	
+	// ------------------------------------------------------------------------
+	
+	public static final ParametrizedRead<Resource, String> NAME = new ParametrizedRead<Resource, String>() {
+
+		@Override
+		public Read<String> get(Resource resource) {
+			return name(resource);
+		}
+		
+	};
+	
+	// ------------------------------------------------------------------------
+	
+}