bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/ValueQuery.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in 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.impl.query;
  13
  14 import org.simantics.db.exception.DatabaseException;
  15 import org.simantics.db.impl.graph.ReadGraphImpl;
  16 import org.simantics.db.impl.procedure.InternalProcedure;
  17
  18 final public class ValueQuery extends UnaryQueryP<byte[]> {
  19
  20     ValueQuery(final int resource) {
  21         super(resource);
  22     }
  23
  24         @Override
  25         final public void removeEntry(QueryProcessor provider) {
  26                 provider.cache.remove(this);
  27         }
  28
  29         @Override
  30         public void compute(ReadGraphImpl graph, InternalProcedure<byte[]> procedure) throws DatabaseException {
  31             computeForEach(graph, id, this, procedure);
  32         }
  33
  34         public static byte[] computeForEach(ReadGraphImpl graph, final int r, final ValueQuery entry, final InternalProcedure<byte[]> procedure_) throws DatabaseException {
  35
  36             InternalProcedure<byte[]> procedure = entry != null ? entry : procedure_;
  37
  38                 graph.ensureLoaded(r);
  39
  40                 byte[] value = graph.getValue(r);
  41                 if(procedure != null) procedure.execute(graph, value);
  42
  43                 if(entry != null && procedure_ != null) entry.performFromCache(graph, procedure_);
  44
  45                 return value;
  46
  47         }
  48
  49     @Override
  50     public String toString() {
  51         return "Value[" + id + "]";
  52     }
  53
  54 }