bundles/org.simantics.db.indexing/src/org/simantics/db/indexing/internal/IndexingJob.java

   1 /*******************************************************************************
   2  * Copyright (c) 2016 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  *     Semantum Oy - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.db.indexing.internal;
  13
  14 import java.util.concurrent.Semaphore;
  15
  16 import org.eclipse.core.runtime.IProgressMonitor;
  17 import org.eclipse.core.runtime.IStatus;
  18 import org.eclipse.core.runtime.jobs.Job;
  19 import org.simantics.db.exception.DatabaseException;
  20 import org.simantics.db.function.DbConsumer;
  21
  22 /**
  23  * @author Tuukka Lehtonen
  24  * @since 1.22.2, 1.25.0
  25  */
  26 public abstract class IndexingJob extends Job {
  27
  28     /**
  29      * NOTE: this is intentionally the same as
  30      * <code>org.simantics.DatabaseJob.DATABASE_JOB_FAMILY</code> in order for
  31      * this job to cause the same UI-behavior as DatabaseJob.
  32      */
  33     private static final String DATABASE_JOB_FAMILY = "org.simantics.db.inDatabaseJob";
  34
  35     public IndexingJob(String name) {
  36         super(name);
  37     }
  38
  39     @Override
  40     public boolean belongsTo(Object family) {
  41         return DATABASE_JOB_FAMILY.equals(family);
  42     }
  43
  44     /**
  45      * @param monitor
  46      * @param jobName
  47      * @param consumer
  48      * @throws DatabaseException
  49      */
  50     public static void jobifyIfPossible(
  51             IProgressMonitor monitor,
  52             String jobName,
  53             DbConsumer<IProgressMonitor> consumer)
  54                     throws DatabaseException
  55     {
  56         // Prevent deadlocks by checking preconditions for using a job.
  57         // JobManager is suspended e.g. during workbench startup.
  58         if (Job.getJobManager().isSuspended() || Job.getJobManager().currentJob() != null) {
  59             consumer.accept(monitor);
  60             return;
  61         }
  62
  63         Semaphore barrier = new Semaphore(0);
  64         Throwable[] err = { null };
  65         IndexingJob job = new IndexingJob(jobName) {
  66             @Override
  67             protected IStatus run(IProgressMonitor monitor) {
  68                 try {
  69                     consumer.accept(monitor);
  70                 } catch (Throwable t) {
  71                     err[0] = t;
  72                 } finally {
  73                     monitor.done();
  74                     barrier.release();
  75                 }
  76                 return org.eclipse.core.runtime.Status.OK_STATUS;
  77             }
  78         };
  79         job.schedule();
  80         try {
  81             barrier.acquire();
  82             if (err[0] != null) {
  83                 if (err[0] instanceof DatabaseException)
  84                     throw (DatabaseException) err[0];
  85                 throw new DatabaseException(err[0]);
  86             }
  87         } catch (InterruptedException e) {
  88             throw new DatabaseException(e);
  89         }
  90     }
  91
  92 }