bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/variable/VariableBinding.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2011 Association for Decentralized Information Management in
   3  * Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.db.layer0.variable;
  13
  14 import org.simantics.databoard.Datatypes;
  15 import org.simantics.databoard.binding.StringBinding;
  16 import org.simantics.databoard.binding.error.BindingException;
  17 import org.simantics.db.Session;
  18 import org.simantics.db.exception.DatabaseException;
  19 import org.simantics.db.layer0.request.ResourceURIToVariable;
  20 import org.simantics.db.layer0.request.VariableURI;
  21
  22 /**
  23  * This class binds Variable to StringType
  24  *
  25  * @author toni.kalajainen
  26  */
  27 public class VariableBinding extends StringBinding {
  28
  29     Session session;
  30
  31     public VariableBinding(Session session) {
  32         super(Datatypes.STRING);
  33         this.session = session;
  34     }
  35
  36     @Override
  37     public boolean isImmutable() {
  38         return true;
  39     }
  40
  41         @Override
  42         public Object create(String value) throws BindingException {
  43                 if ( session == null ) throw new BindingException("Cannot create Variable without a Session");
  44                 try {
  45                         return session.sync( new ResourceURIToVariable( value ) );
  46                 } catch (DatabaseException e) {
  47                         throw new BindingException(e);
  48                 }
  49         }
  50
  51         @Override
  52         public String getValue(Object o) throws BindingException {
  53                 if ( session == null ) throw new BindingException("Cannot create Variable without a Session");
  54                 if (o instanceof Variable==false) throw new BindingException("Not a variable");
  55                 Variable v = (Variable) o;
  56                 try {
  57                         return (String) session.sync( new VariableURI( v ) );
  58                 } catch (DatabaseException e) {
  59                         throw new BindingException( e );
  60                 }
  61         }
  62
  63         @Override
  64         public void setValue(Object o, String newValue) throws BindingException {
  65                 throw new BindingException("Cannot set URI to Variable. URI is immutable");
  66         }
  67
  68         @Override
  69         public boolean isInstance(Object obj) {
  70                 return obj instanceof Variable;
  71         }
  72
  73 }