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 import org.simantics.db.indexing.exception.IndexingException;
  22
  23 /**
  24  * @author Tuukka Lehtonen
  25  * @since 1.22.2, 1.25.0
  26  */
  27 public abstract class IndexingJob extends Job {
  28
  29     /**
  30      * NOTE: this is intentionally the same as
  31      * <code>org.simantics.DatabaseJob.DATABASE_JOB_FAMILY</code> in order for
  32      * this job to cause the same UI-behavior as DatabaseJob.
  33      */
  34     private static final String DATABASE_JOB_FAMILY = "org.simantics.db.inDatabaseJob";
  35
  36     public IndexingJob(String name) {
  37         super(name);
  38     }
  39
  40     @Override
  41     public boolean belongsTo(Object family) {
  42         return DATABASE_JOB_FAMILY.equals(family);
  43     }
  44
  45     /**
  46      * @param monitor
  47      * @param jobName
  48      * @param consumer
  49      * @throws DatabaseException
  50      */
  51     public static void jobifyIfPossible(
  52             IProgressMonitor monitor,
  53             String jobName,
  54             DbConsumer<IProgressMonitor> consumer)
  55                     throws DatabaseException
  56     {
  57         // Prevent deadlocks by checking preconditions for using a job.
  58         // JobManager is suspended e.g. during workbench startup.
  59         if (Job.getJobManager().isSuspended() || Job.getJobManager().currentJob() != null) {
  60             consumer.accept(monitor);
  61             return;
  62         }
  63
  64         Semaphore barrier = new Semaphore(0);
  65         Throwable[] err = { null };
  66         IndexingJob job = new IndexingJob(jobName) {
  67             @Override
  68             protected IStatus run(IProgressMonitor monitor) {
  69                 try {
  70                     consumer.accept(monitor);
  71                 } catch (Throwable t) {
  72                     err[0] = t;
  73                 } finally {
  74                     monitor.done();
  75                     barrier.release();
  76                 }
  77                 return org.eclipse.core.runtime.Status.OK_STATUS;
  78             }
  79         };
  80         job.schedule();
  81         try {
  82             barrier.acquire();
  83             if (err[0] != null) {
  84                 if (err[0] instanceof IndexingException)
  85                     throw (DatabaseException) err[0];
  86                 throw new IndexingException(err[0]);
  87             }
  88         } catch (InterruptedException e) {
  89             throw new IndexingException(e);
  90         }
  91     }
  92
  93 }