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diff --git a/bundles/org.simantics.databoard/src/org/simantics/databoard/binding/mutable/Variant.java b/bundles/org.simantics.databoard/src/org/simantics/databoard/binding/mutable/Variant.java
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+/*******************************************************************************
+ * Copyright (c) 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.databoard.binding.mutable;
+
+import java.io.IOException;
+
+import org.simantics.databoard.Accessors;
+import org.simantics.databoard.Bindings;
+import org.simantics.databoard.accessor.VariantAccessor;
+import org.simantics.databoard.accessor.error.AccessorConstructionException;
+import org.simantics.databoard.accessor.java.JavaObject;
+import org.simantics.databoard.accessor.reference.ChildReference;
+import org.simantics.databoard.adapter.AdaptException;
+import org.simantics.databoard.binding.Binding;
+import org.simantics.databoard.binding.error.BindingException;
+import org.simantics.databoard.binding.error.RuntimeBindingException;
+import org.simantics.databoard.binding.reflection.VoidBinding;
+import org.simantics.databoard.parser.DataValuePrinter;
+import org.simantics.databoard.parser.PrintFormat;
+import org.simantics.databoard.parser.repository.DataValueRepository;
+import org.simantics.databoard.parser.unparsing.DataTypePrinter;
+import org.simantics.databoard.type.Datatype;
+
+/**
+ * Variant is a container to a data value of any type. 
+ * This very class is immutable, the value and type cannot be changed, but the 
+ * sub-class {@link MutableVariant} is not. <p>
+ *
+ * Variant is hash-equals-comparable, even variants of bindings (and types). 
+ * The hash function and comparison rules are defined in the manual.  <p>
+ *
+ * @see ImmutableVariantBinding is binding for Variant-class
+ * @author Toni Kalajainen <toni.kalajainen@vtt.fi>
+ */
+public class Variant implements Comparable<Variant>, Cloneable {
+	
+	public static Variant ofInstance(Object instance) {
+		Binding binding = Bindings.getBindingUnchecked( instance.getClass() );
+		return new Variant(binding, instance);
+	}
+	
+	Binding binding;
+	Object value;
+	
+	/**
+	 * Constract a variant with a default value of empty record {}
+	 */
+	public Variant() {
+		binding = VoidBinding.VOID_BINDING;
+		value = null;
+	}
+
+	public Variant(Variant v) {
+		//assert(isValid(binding, value));
+		this.binding = v.getBinding();
+		this.value = v.getValue();
+	}	
+	
+	public Variant(Binding binding, Object value) {
+		//assert(isValid(binding, value));
+		this.binding = binding;
+		this.value = value;
+	}
+	
+	public Object getValue() {
+		return value;
+	}
+
+	/**
+	 * Get and if necessary and possible, type-adapt the value.
+	 * 
+	 * @param binding
+	 * @return the value in given binding
+	 * @throws AdaptException
+	 */
+	public Object getValue(Binding binding) throws AdaptException {
+		return Bindings.adapt(value, this.binding, binding);
+	}
+
+	public VariantAccessor getAccessor() {
+		try {
+			return (VariantAccessor) Accessors.getAccessor( Bindings.VARIANT, this);
+		} catch (AccessorConstructionException e) {
+			// Unexpected
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public Datatype type() {
+		return binding.type();
+	}
+	
+	public Binding getBinding() {
+		return binding;
+	}
+	
+	@Override
+	public int hashCode() {
+		try {
+			return binding.hashValue(value);
+		} catch (BindingException e) {
+			throw new RuntimeBindingException(e);
+		}
+	}
+	
+	@Override
+	public boolean equals(Object obj) {
+		if(this == obj)
+			return true;
+		if(obj == null)
+			return false;
+		if(!(obj instanceof Variant))
+			return false;
+		try {
+			Variant o = (Variant) obj;
+			if (o.binding==binding && o.value == value) return true;
+			return Bindings.equals(binding, value, o.binding, o.value);
+		} catch (BindingException e) {
+			throw new RuntimeBindingException(e);
+		}
+	}
+	
+	public boolean valueEquals(Binding binding, Object obj)
+	{
+		if (this.binding == binding) return binding.equals(obj, this.value);
+		Object adapted;
+		try {
+			adapted = Bindings.adapt(obj, binding, this.binding);
+			return this.binding.equals(adapted, this.value);
+		} catch (AdaptException e) {
+			return false;
+		}
+	}
+	
+	@Override
+	public int compareTo(Variant o) {
+		try {
+			if (o.binding==binding && o.value == value) return 0;
+			return Bindings.compare(binding, value, o.binding, o.value);
+		} catch (BindingException e) {
+			throw new RuntimeBindingException(e);
+		}
+	}
+	
+	@Override
+	public String toString() {
+		try {
+			StringBuilder sb = new StringBuilder();			
+			DataValueRepository repo = new DataValueRepository();
+			DataValuePrinter printer = new DataValuePrinter(sb, repo);
+			printer.setFormat(PrintFormat.SINGLE_LINE);
+			printer.print(binding, value);
+			sb.append(" : ");
+			DataTypePrinter printer2 = new DataTypePrinter(sb);
+			printer2.print(binding.type());
+			return sb.toString();
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		} catch (BindingException e) {
+			throw new RuntimeBindingException(e);
+		}
+	}
+	
+	public Variant clone() {
+		if (binding.isImmutable()) return new Variant(binding, value);
+		Object newValue = Bindings.cloneUnchecked(value, binding, binding);
+		return new Variant(binding, newValue);
+	}
+
+	boolean isValid(Binding binding, Object obj) throws RuntimeBindingException {
+		try {
+			binding.assertInstaceIsValid(obj);
+			return true;
+		} catch (BindingException e) {
+			throw new RuntimeBindingException(e);
+		}
+	}
+
+	
+	/**
+	 * Open a variant to a component object.
+	 *  
+	 * @param ref child reference, if null then this object is returned
+	 * @return variant to this or new variant that refers to actual child object
+	 * @throws AccessorConstructionException 
+	 */
+	public Variant getComponent(ChildReference ref) throws AccessorConstructionException {
+		if ( ref == null ) return this;
+		JavaObject jo = (JavaObject) Accessors.getAccessor(this, ref);
+		return new Variant( jo.getBinding(), jo.getObject() );
+	}
+		
+}
+
+