SONAR-249 add the decorator to calculate differential values of measures.

13 files changed, 663 insertions, 34 deletions

diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/CorePlugin.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/CorePlugin.java
index b18eeff5366..ae915535904 100644
--- a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/CorePlugin.java
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/CorePlugin.java
@@ -19,7 +19,11 @@
  */
 package org.sonar.plugins.core;
 
-import org.sonar.api.*;
+import com.google.common.collect.Lists;
+import org.sonar.api.CoreProperties;
+import org.sonar.api.Plugin;
+import org.sonar.api.Properties;
+import org.sonar.api.Property;
 import org.sonar.api.checks.NoSonarFilter;
 import org.sonar.api.resources.Java;
 import org.sonar.plugins.core.batch.ExcludedResourceFilter;
@@ -36,11 +40,13 @@ import org.sonar.plugins.core.metrics.UserManagedMetrics;
 import org.sonar.plugins.core.security.ApplyProjectRolesDecorator;
 import org.sonar.plugins.core.sensors.*;
 import org.sonar.plugins.core.testdetailsviewer.TestsViewerDefinition;
+import org.sonar.plugins.core.timemachine.DifferentialValueDecorator;
+import org.sonar.plugins.core.timemachine.PeriodLocator;
+import org.sonar.plugins.core.timemachine.TendencyDecorator;
 import org.sonar.plugins.core.ui.pageselector.GwtPageSelector;
 import org.sonar.plugins.core.violationsviewer.ViolationsViewerDefinition;
 import org.sonar.plugins.core.widgets.*;
 
-import java.util.ArrayList;
 import java.util.List;
 
 @Properties({
@@ -125,7 +131,7 @@ public class CorePlugin implements Plugin {
   }
 
   public List getExtensions() {
-    List extensions = new ArrayList();
+    List extensions = Lists.newLinkedList();
 
     // languages
     extensions.add(Java.class);
@@ -186,6 +192,9 @@ public class CorePlugin implements Plugin {
     extensions.add(DirectoriesDecorator.class);
     extensions.add(FilesDecorator.class);
 
+    extensions.add(PeriodLocator.class);
+    extensions.add(DifferentialValueDecorator.class);
+
     return extensions;
   }
 
diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/CheckAlertThresholds.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/CheckAlertThresholds.java
index 8e55fa3890d..5b3be2accff 100644
--- a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/CheckAlertThresholds.java
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/CheckAlertThresholds.java
@@ -19,11 +19,9 @@
  */
 package org.sonar.plugins.core.sensors;
 
+import com.google.common.collect.Lists;
 import org.apache.commons.lang.StringUtils;
-import org.sonar.api.batch.Decorator;
-import org.sonar.api.batch.DecoratorContext;
-import org.sonar.api.batch.DependedUpon;
-import org.sonar.api.batch.Phase;
+import org.sonar.api.batch.*;
 import org.sonar.api.measures.CoreMetrics;
 import org.sonar.api.measures.Measure;
 import org.sonar.api.measures.Metric;
@@ -33,10 +31,8 @@ import org.sonar.api.resources.Project;
 import org.sonar.api.resources.Resource;
 import org.sonar.api.resources.ResourceUtils;
 
-import java.util.ArrayList;
 import java.util.List;
 
-@Phase(name = Phase.Name.POST)
 public class CheckAlertThresholds implements Decorator {
 
   private final RulesProfile profile;
@@ -50,6 +46,15 @@ public class CheckAlertThresholds implements Decorator {
     return CoreMetrics.ALERT_STATUS;
   }
 
+  @DependsUpon
+  public List<Metric> dependsUponMetrics() {
+    List<Metric> metrics = Lists.newLinkedList();
+    for (Alert alert : profile.getAlerts()) {
+      metrics.add(alert.getMetric());
+    }
+    return metrics;
+  }
+
 
   public boolean shouldExecuteOnProject(Project project) {
     return profile != null
@@ -66,7 +71,7 @@ public class CheckAlertThresholds implements Decorator {
 
   private void decorateResource(DecoratorContext context) {
     Metric.Level globalLevel = Metric.Level.OK;
-    List<String> labels = new ArrayList<String>();
+    List<String> labels = Lists.newArrayList();
 
     for (final Alert alert : profile.getAlerts()) {
       Measure measure = context.getMeasure(alert.getMetric());
diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/GenerateAlertEvents.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/GenerateAlertEvents.java
index f8af4708d3f..62b8882fd2d 100644
--- a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/GenerateAlertEvents.java
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/GenerateAlertEvents.java
@@ -30,7 +30,6 @@ import org.sonar.api.resources.ResourceUtils;
 
 import java.util.List;
 
-@Phase(name = Phase.Name.POST)
 public class GenerateAlertEvents implements Decorator {
 
   private final RulesProfile profile;
diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/DifferentialValueDecorator.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/DifferentialValueDecorator.java
new file mode 100644
index 00000000000..57c9c5619ed
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/DifferentialValueDecorator.java
@@ -0,0 +1,200 @@
+/*
+ * Sonar, open source software quality management tool.
+ * Copyright (C) 2009 SonarSource SA
+ * mailto:contact AT sonarsource DOT com
+ *
+ * Sonar is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * Sonar is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Sonar; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package org.sonar.plugins.core.timemachine;
+
+import com.google.common.collect.Maps;
+import org.apache.commons.configuration.Configuration;
+import org.apache.commons.lang.ObjectUtils;
+import org.sonar.api.batch.*;
+import org.sonar.api.database.DatabaseSession;
+import org.sonar.api.database.model.MeasureModel;
+import org.sonar.api.database.model.Snapshot;
+import org.sonar.api.measures.*;
+import org.sonar.api.qualitymodel.Characteristic;
+import org.sonar.api.resources.Project;
+import org.sonar.api.resources.Resource;
+import org.sonar.api.rules.Rule;
+import org.sonar.api.rules.RulePriority;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+@DependedUpon(DecoratorBarriers.END_OF_TIME_MACHINE)
+public class DifferentialValueDecorator implements Decorator {
+
+  private Snapshot[] projectTargetSnapshots;
+  private Map<Integer, Metric> metricByIds;
+  private DatabaseSession session;
+
+  public DifferentialValueDecorator(DatabaseSession session, PeriodLocator periodLocator, Configuration configuration, MetricFinder metricFinder) {
+    this.session = session;
+    Snapshot snapshot = periodLocator.locate(5);
+    projectTargetSnapshots = new Snapshot[] {snapshot};
+
+    this.metricByIds = Maps.newHashMap();
+    for (Metric metric : metricFinder.findAll()) {
+      if (metric.isNumericType()) {
+        metricByIds.put(metric.getId(), metric);
+      }
+    }
+  }
+
+  /**
+   * only for unit tests
+   */
+  DifferentialValueDecorator(DatabaseSession session, Snapshot[] projectTargetSnapshots, Metric[] metrics) {
+    this.session = session;
+    this.projectTargetSnapshots = projectTargetSnapshots;
+    this.metricByIds = Maps.newHashMap();
+    for (Metric metric : metrics) {
+      metricByIds.put(metric.getId(), metric);
+    }
+  }
+
+  public boolean shouldExecuteOnProject(Project project) {
+    return true;
+  }
+
+  @DependsUpon
+  public Collection<Metric> dependsUponMetrics() {
+    return metricByIds.values();
+  }
+
+  public void decorate(Resource resource, DecoratorContext context) {
+    for (int index = 0; index < projectTargetSnapshots.length; index++) {
+      Snapshot projectTargetSnapshot = projectTargetSnapshots[index];
+      if (projectTargetSnapshot != null) {
+        // search past measures
+        List<MeasureModel> pastMeasures = selectPastMeasures(resource.getId(), projectTargetSnapshot);
+
+        Map<MeasureKey, MeasureModel> pastMeasuresByKey = Maps.newHashMap();
+        for (MeasureModel pastMeasure : pastMeasures) {
+          pastMeasuresByKey.put(new MeasureKey(pastMeasure), pastMeasure);
+        }
+
+        // for each measure, search equivalent past measure
+        for (Measure measure : context.getMeasures(MeasuresFilters.all())) {
+          // compare with past measure
+          MeasureModel pastMeasure = pastMeasuresByKey.get(new MeasureKey(measure));
+          if (calculateDiffValue(measure, pastMeasure, index)) {
+            context.saveMeasure(measure);
+          }
+        }
+      }
+    }
+  }
+
+  private boolean calculateDiffValue(Measure measure, MeasureModel pastMeasure, int index) {
+    boolean updated = false;
+    if (pastMeasure != null && pastMeasure.getValue() != null && measure.getValue() != null) {
+      double diff = (measure.getValue().doubleValue() - pastMeasure.getValue().doubleValue());
+      updated = true;
+      switch (index) {
+        case 0:
+          measure.setDiffValue1(diff);
+          break;
+        case 1:
+          measure.setDiffValue2(diff);
+          break;
+        case 2:
+          measure.setDiffValue3(diff);
+          break;
+        default:
+          updated = false;
+      }
+    }
+    return updated;
+  }
+
+  List<MeasureModel> selectPastMeasures(int resourceId, Snapshot projectTargetSnapshot) {
+    // improvements : keep query in cache ? select only some columns ?
+    // TODO support measure on rules and characteristics
+    String hql = "select m from " + MeasureModel.class.getSimpleName() + " m, " + Snapshot.class.getSimpleName() + " s " +
+        "where m.snapshotId=s.id and m.metricId in (:metricIds) and m.rule=null and m.rulePriority=null and m.rulesCategoryId=null and m.characteristic=null "
+        + "and (s.rootId=:rootSnapshotId or s.id=:rootSnapshotId) and s.resourceId=:resourceId and s.status=:status";
+    return session.createQuery(hql)
+        .setParameter("metricIds", metricByIds.keySet())
+        .setParameter("rootSnapshotId", ObjectUtils.defaultIfNull(projectTargetSnapshot.getRootId(), projectTargetSnapshot.getId()))
+        .setParameter("resourceId", resourceId)
+        .setParameter("status", Snapshot.STATUS_PROCESSED)
+        .getResultList();
+  }
+
+  @Override
+  public String toString() {
+    return getClass().toString();
+  }
+
+  static class MeasureKey {
+    Integer metricId;
+    Rule rule;
+    Integer categoryId;
+    RulePriority priority;
+    Characteristic characteristic;
+
+    MeasureKey(MeasureModel model) {
+      this.metricId = model.getMetricId();
+      rule = model.getRule();
+      categoryId = model.getRulesCategoryId();
+      priority = model.getRulePriority();
+      characteristic = model.getCharacteristic();
+    }
+
+    MeasureKey(Measure measure) {
+      metricId = measure.getMetric().getId();
+      characteristic = measure.getCharacteristic();
+      // TODO merge RuleMeasure into Measure
+      if (measure instanceof RuleMeasure) {
+        RuleMeasure rm = (RuleMeasure)measure;
+        categoryId = rm.getRuleCategory();
+        rule = rm.getRule();
+        priority = rm.getRulePriority();
+      }
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) return true;
+      if (o == null || getClass() != o.getClass()) return false;
+
+      MeasureKey that = (MeasureKey) o;
+
+      if (categoryId != null ? !categoryId.equals(that.categoryId) : that.categoryId != null) return false;
+      if (characteristic != null ? !characteristic.equals(that.characteristic) : that.characteristic != null)
+        return false;
+      if (!metricId.equals(that.metricId)) return false;
+      if (priority != that.priority) return false;
+      if (rule != null ? !rule.equals(that.rule) : that.rule != null) return false;
+
+      return true;
+    }
+
+    @Override
+    public int hashCode() {
+      int result = metricId.hashCode();
+      result = 31 * result + (rule != null ? rule.hashCode() : 0);
+      result = 31 * result + (categoryId != null ? categoryId.hashCode() : 0);
+      result = 31 * result + (priority != null ? priority.hashCode() : 0);
+      result = 31 * result + (characteristic != null ? characteristic.hashCode() : 0);
+      return result;
+    }
+  }
+}
diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/PeriodLocator.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/PeriodLocator.java
new file mode 100644
index 00000000000..35e960023b1
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/PeriodLocator.java
@@ -0,0 +1,74 @@
+/*
+ * Sonar, open source software quality management tool.
+ * Copyright (C) 2009 SonarSource SA
+ * mailto:contact AT sonarsource DOT com
+ *
+ * Sonar is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * Sonar is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Sonar; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package org.sonar.plugins.core.timemachine;
+
+import org.apache.commons.lang.time.DateUtils;
+import org.sonar.api.BatchExtension;
+import org.sonar.api.database.DatabaseSession;
+import org.sonar.api.database.model.Snapshot;
+
+import java.util.Date;
+import java.util.List;
+
+// TODO should implement BatchComponent
+public final class PeriodLocator implements BatchExtension {
+  private Snapshot projectSnapshot; // TODO replace by PersistenceManager
+  private DatabaseSession session;
+
+  public PeriodLocator(Snapshot projectSnapshot, DatabaseSession session) {
+    this.projectSnapshot = projectSnapshot;
+    this.session = session;
+  }
+
+  public Snapshot locate(int days) {
+    List<Snapshot> snapshots = loadSnapshotsFromDatabase();
+    return getNearestToTarget(snapshots, projectSnapshot.getCreatedAt(), days);
+  }
+
+  List<Snapshot> loadSnapshotsFromDatabase() {
+    String hql = "from " + Snapshot.class.getSimpleName() + " where resourceId=:resourceId AND status=:status order by createdAt";
+    return session.createQuery(hql)
+        .setParameter("resourceId", projectSnapshot.getResourceId())
+        .setParameter("status", Snapshot.STATUS_PROCESSED)
+        .getResultList();
+  }
+
+  static Snapshot getNearestToTarget(List<Snapshot> snapshots, Date currentDate, int distanceInDays) {
+    Date targetDate = DateUtils.addDays(currentDate, -distanceInDays);
+    return getNearestToTarget(snapshots, targetDate);
+  }
+
+  static Snapshot getNearestToTarget(List<Snapshot> snapshots, Date targetDate) {
+    long bestDistance = Long.MAX_VALUE;
+    Snapshot nearest = null;
+    for (Snapshot snapshot : snapshots) {
+      long distance = distance(snapshot.getCreatedAt(), targetDate);
+      if (distance<=bestDistance) {
+        bestDistance = distance;
+        nearest = snapshot;
+      }
+    }
+    return nearest;
+  }
+
+  static long distance(Date d1, Date d2) {
+    return Math.abs(d1.getTime() - d2.getTime());
+  }
+}
diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/TendencyAnalyser.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/TendencyAnalyser.java
index 0ffde81e912..16ccf41df5d 100644
--- a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/TendencyAnalyser.java
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/TendencyAnalyser.java
@@ -17,7 +17,7 @@
  * License along with Sonar; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02

  */

-package org.sonar.plugins.core.sensors;

+package org.sonar.plugins.core.timemachine;

 

 import java.util.List;

 

diff --git a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/TendencyDecorator.java b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/TendencyDecorator.java
index 4a0c9537704..c28c1f52084 100644
--- a/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/sensors/TendencyDecorator.java
+++ b/plugins/sonar-core-plugin/src/main/java/org/sonar/plugins/core/timemachine/TendencyDecorator.java
@@ -17,40 +17,45 @@
  * License along with Sonar; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
  */
-package org.sonar.plugins.core.sensors;
+package org.sonar.plugins.core.timemachine;
 
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.ListMultimap;
+import com.google.common.collect.Lists;
 import org.apache.commons.configuration.Configuration;
 import org.apache.commons.lang.time.DateUtils;
 import org.sonar.api.CoreProperties;
 import org.sonar.api.batch.*;
 import org.sonar.api.measures.Measure;
 import org.sonar.api.measures.Metric;
+import org.sonar.api.measures.MetricFinder;
 import org.sonar.api.resources.Project;
 import org.sonar.api.resources.Resource;
 import org.sonar.api.resources.ResourceUtils;
-import org.sonar.jpa.dao.MeasuresDao;
 
-import java.util.ArrayList;
 import java.util.List;
 
-@Phase(name = Phase.Name.POST)
+@DependedUpon(DecoratorBarriers.END_OF_TIME_MACHINE)
 public class TendencyDecorator implements Decorator {
 
   public static final String PROP_DAYS_DESCRIPTION = "Number of days the tendency should be calculated on.";
 
-  private MeasuresDao measuresDao;
   private TimeMachine timeMachine;
   private TimeMachineQuery query;
   private TendencyAnalyser analyser;
   private Configuration configuration;
+  private List<Metric> metrics;
 
-  public TendencyDecorator(TimeMachine timeMachine, MeasuresDao measuresDao, Configuration configuration) {
+  public TendencyDecorator(TimeMachine timeMachine, MetricFinder metricFinder, Configuration configuration) {
     this.timeMachine = timeMachine;
-    this.measuresDao = measuresDao;
     this.analyser = new TendencyAnalyser();
     this.configuration = configuration;
+    this.metrics = Lists.newLinkedList();
+    for (Metric metric : metricFinder.findAll()) {
+      if (metric.isNumericType()) {
+        metrics.add(metric);
+      }
+    }
   }
 
   protected TendencyDecorator(TimeMachine timeMachine, TimeMachineQuery query, TendencyAnalyser analyser, Configuration configuration) {
@@ -60,16 +65,14 @@ public class TendencyDecorator implements Decorator {
     this.configuration = configuration;
   }
 
+  @DependsUpon
+  public List<Metric> dependsUponMetrics() {
+    return metrics;
+  }
+
   protected TimeMachineQuery initQuery(Project project) {
     int days = project.getConfiguration().getInt(CoreProperties.CORE_TENDENCY_DEPTH_PROPERTY, CoreProperties.CORE_TENDENCY_DEPTH_DEFAULT_VALUE);
 
-    List<Metric> metrics = new ArrayList<Metric>();
-    for (Metric metric : measuresDao.getMetrics()) {
-      if (metric.isNumericType()) {
-        metrics.add(metric);
-      }
-    }
-
     query = new TimeMachineQuery(null) // resource is set after
         .setFrom(DateUtils.addDays(project.getAnalysisDate(), -days))
         .setToCurrentAnalysis(true)
diff --git a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest.java b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest.java
new file mode 100644
index 00000000000..bf4691d01d1
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest.java
@@ -0,0 +1,78 @@
+/*
+ * Sonar, open source software quality management tool.
+ * Copyright (C) 2009 SonarSource SA
+ * mailto:contact AT sonarsource DOT com
+ *
+ * Sonar is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * Sonar is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Sonar; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package org.sonar.plugins.core.timemachine;
+
+import org.junit.Test;
+import org.sonar.api.database.model.MeasureModel;
+import org.sonar.api.database.model.Snapshot;
+import org.sonar.api.measures.Metric;
+import org.sonar.jpa.test.AbstractDbUnitTestCase;
+
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.anyOf;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class DifferentialValueDecoratorTest extends AbstractDbUnitTestCase {
+
+  private static final int PROJECT_SNAPSHOT_ID = 1000;
+  private static final int PROJECT_ID = 1;
+  private static final int FILE_ID = 3;
+
+  @Test
+  public void shouldSelectPastResourceMeasures() {
+    setupData("shared");
+
+    Metric[] metrics = selectMetrics();
+    Snapshot projectSnapshot = getSession().getSingleResult(Snapshot.class, "id", PROJECT_SNAPSHOT_ID);
+
+    DifferentialValueDecorator decorator = new DifferentialValueDecorator(getSession(), new Snapshot[0], metrics);
+    List<MeasureModel> measures = decorator.selectPastMeasures(FILE_ID, projectSnapshot);
+    assertThat(measures.size(), is(2));
+
+    for (MeasureModel measure : measures) {
+      assertThat(measure.getId(), anyOf(is(5L), is(6L)));
+      assertThat(measure.getValue(), anyOf(is(5.0), is(60.0)));
+    }
+  }
+
+  @Test
+  public void shouldSelectPastProjectMeasures() {
+    setupData("shared");
+
+    Metric[] metrics = selectMetrics();
+    Snapshot projectSnapshot = getSession().getSingleResult(Snapshot.class, "id", PROJECT_SNAPSHOT_ID);
+
+    DifferentialValueDecorator decorator = new DifferentialValueDecorator(getSession(), new Snapshot[0], metrics);
+    List<MeasureModel> measures = decorator.selectPastMeasures(PROJECT_ID, projectSnapshot);
+    assertThat(measures.size(), is(2));
+
+    for (MeasureModel measure : measures) {
+      assertThat(measure.getId(), anyOf(is(1L), is(2L)));
+      assertThat(measure.getValue(), anyOf(is(60.0), is(80.0)));
+    }
+  }
+
+  private Metric[] selectMetrics() {
+    List<Metric> metrics = getSession().getResults(Metric.class);
+    return metrics.toArray(new Metric[metrics.size()]);
+  }
+}
diff --git a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/PeriodLocatorTest.java b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/PeriodLocatorTest.java
new file mode 100644
index 00000000000..d0d99fed25f
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/PeriodLocatorTest.java
@@ -0,0 +1,99 @@
+/*
+ * Sonar, open source software quality management tool.
+ * Copyright (C) 2009 SonarSource SA
+ * mailto:contact AT sonarsource DOT com
+ *
+ * Sonar is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * Sonar is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Sonar; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package org.sonar.plugins.core.timemachine;
+
+import com.google.common.collect.Lists;
+import org.junit.Test;
+import org.sonar.api.database.model.Snapshot;
+import org.sonar.jpa.test.AbstractDbUnitTestCase;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Date;
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.core.IsNull.nullValue;
+import static org.junit.Assert.assertThat;
+import static org.junit.internal.matchers.IsCollectionContaining.hasItems;
+
+public class PeriodLocatorTest extends AbstractDbUnitTestCase {
+
+  private static SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
+
+  @Test
+  public void shouldLoadSnapshotsFromDatabase() {
+    setupData("shouldLoadSnapshotsFromDatabase");
+
+    Snapshot projectSnapshot = getSession().getSingleResult(Snapshot.class, "id", 1009);
+    PeriodLocator locator = new PeriodLocator(projectSnapshot, getSession());
+    List<Snapshot> snapshots = locator.loadSnapshotsFromDatabase();
+    List<Integer> snapshotIds = Lists.newLinkedList();
+    for (Snapshot snapshot : snapshots) {
+      snapshotIds.add(snapshot.getId());
+    }
+    assertThat(snapshotIds.size(), is(2));
+    assertThat(snapshotIds, hasItems(1000, 1003)); // project snapshots
+  }
+
+  @Test
+  public void shouldLocateNearestSnapshotBefore() throws ParseException {
+    Date current = dateFormat.parse("2010-10-20");
+    // distance: 15 => target is 2010-10-05
+
+    List<Snapshot> snapshots = Arrays.asList(
+        newSnapshot(1, "2010-09-30"),
+        newSnapshot(2, "2010-10-03"),// -2 days
+        newSnapshot(3, "2010-10-08"),// +3 days
+        newSnapshot(4, "2010-10-12") // + 7 days
+    );
+    assertThat(PeriodLocator.getNearestToTarget(snapshots, current, 15).getId(), is(2));
+  }
+
+  @Test
+  public void shouldLocateNearestSnapshotAfter() throws ParseException {
+    Date current = dateFormat.parse("2010-10-20");
+    // distance: 15 => target is 2010-10-05
+
+    List<Snapshot> snapshots = Arrays.asList(
+        newSnapshot(1, "2010-09-30"),
+        newSnapshot(2, "2010-10-01"),// -4 days
+        newSnapshot(3, "2010-10-08"),// +3 days
+        newSnapshot(4, "2010-10-12") // + 7 days
+    );
+    assertThat(PeriodLocator.getNearestToTarget(snapshots, current, 15).getId(), is(3));
+  }
+
+  @Test
+  public void shouldReturnNullIfNoSnapshots() throws ParseException {
+    Date current = dateFormat.parse("2010-10-20");
+    List<Snapshot> snapshots = Collections.emptyList();
+    assertThat(PeriodLocator.getNearestToTarget(snapshots, current, 15), nullValue());
+  }
+
+  private Snapshot newSnapshot(int id, String date) throws ParseException {
+    Snapshot snapshot = new Snapshot();
+    snapshot.setId(id);
+    snapshot.setCreatedAt(dateFormat.parse(date));
+    return snapshot;
+  }
+}
diff --git a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/sensors/TendencyAnalyserTest.java b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/TendencyAnalyserTest.java
index 2bab29d3f8b..15acb78854d 100644
--- a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/sensors/TendencyAnalyserTest.java
+++ b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/TendencyAnalyserTest.java
@@ -17,16 +17,17 @@
  * License along with Sonar; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02

  */

-package org.sonar.plugins.core.sensors;

+package org.sonar.plugins.core.timemachine;

 

-import static org.hamcrest.CoreMatchers.nullValue;

-import static org.junit.Assert.*;

 import org.junit.Test;

 

 import java.util.Arrays;

 import java.util.Collections;

 import java.util.List;

 

+import static org.hamcrest.CoreMatchers.nullValue;

+import static org.junit.Assert.*;

+

 public class TendencyAnalyserTest {

   private TendencyAnalyser analyser = new TendencyAnalyser();

 

diff --git a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/sensors/TendencyDecoratorTest.java b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/TendencyDecoratorTest.java
index 2a2d26a13b1..e37d54ee5a8 100644
--- a/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/sensors/TendencyDecoratorTest.java
+++ b/plugins/sonar-core-plugin/src/test/java/org/sonar/plugins/core/timemachine/TendencyDecoratorTest.java
@@ -17,7 +17,7 @@
  * License along with Sonar; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
  */
-package org.sonar.plugins.core.sensors;
+package org.sonar.plugins.core.timemachine;
 
 import org.apache.commons.configuration.PropertiesConfiguration;
 import org.junit.Test;
@@ -27,9 +27,9 @@ import org.sonar.api.batch.TimeMachine;
 import org.sonar.api.batch.TimeMachineQuery;
 import org.sonar.api.measures.CoreMetrics;
 import org.sonar.api.measures.Measure;
+import org.sonar.api.measures.MetricFinder;
 import org.sonar.api.resources.JavaPackage;
 import org.sonar.api.resources.Project;
-import org.sonar.jpa.dao.MeasuresDao;
 
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
@@ -49,10 +49,10 @@ public class TendencyDecoratorTest {
     when(project.getAnalysisDate()).thenReturn(date("2009-12-25"));
     when(project.getConfiguration()).thenReturn(new PropertiesConfiguration());
 
-    MeasuresDao dao = mock(MeasuresDao.class);
-    when(dao.getMetrics()).thenReturn(Arrays.asList(CoreMetrics.LINES, CoreMetrics.COVERAGE, CoreMetrics.COVERAGE_LINE_HITS_DATA, CoreMetrics.PROFILE));
+    MetricFinder metricFinder = mock(MetricFinder.class);
+    when(metricFinder.findAll()).thenReturn(Arrays.asList(CoreMetrics.LINES, CoreMetrics.COVERAGE, CoreMetrics.COVERAGE_LINE_HITS_DATA, CoreMetrics.PROFILE));
 
-    TendencyDecorator decorator = new TendencyDecorator(null, dao, new PropertiesConfiguration());
+    TendencyDecorator decorator = new TendencyDecorator(null, metricFinder, new PropertiesConfiguration());
 
     TimeMachineQuery query = decorator.initQuery(project);
     assertThat(query.getMetrics().size(), is(2));
diff --git a/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest/shared.xml b/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest/shared.xml
new file mode 100644
index 00000000000..48fe462c4b2
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/DifferentialValueDecoratorTest/shared.xml
@@ -0,0 +1,85 @@
+<dataset>
+
+  <metrics id="1" name="ncloc" VAL_TYPE="INT" DESCRIPTION="[null]"  domain="[null]" short_name=""
+           enabled="true" worst_value="[null]" optimized_best_value="[null]" best_value="[null]" direction="0" hidden="false"/>
+  <metrics id="2" name="coverage" VAL_TYPE="INT" DESCRIPTION="[null]"  domain="[null]" short_name=""
+           enabled="true" worst_value="0" optimized_best_value="true" best_value="100" direction="1" hidden="false"/>
+
+
+  <rules_categories id="1" name="Efficiency" description="[null]"/>
+  <rules_categories id="6" name="Usability" description="[null]"/>
+
+  <rules id="30" name="Check Header" rules_category_id="6" plugin_rule_key="com.puppycrawl.tools.checkstyle.checks.header.HeaderCheck"
+         plugin_config_key="Checker/Treewalker/HeaderCheck" plugin_name="checkstyle" description="[null]" priority="4" enabled="true"
+         cardinality="SINGLE" parent_id="[null]"/>
+
+  <rules id="31" name="Equals Avoid Null" rules_category_id="6" plugin_rule_key="com.puppycrawl.tools.checkstyle.checks.coding.EqualsAvoidNullCheck"
+         plugin_config_key="Checker/TreeWalker/EqualsAvoidNull" plugin_name="checkstyle" description="[null]" priority="4" enabled="true"
+         cardinality="SINGLE" parent_id="[null]"/>
+
+  <!-- project -->
+  <projects long_name="[null]" id="1" scope="PRJ" qualifier="TRK" kee="project" name="project"
+            root_id="[null]"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+  <!-- package -->
+  <projects long_name="[null]" id="2" scope="DIR" qualifier="PAC" kee="project:org.foo" name="org.foo"
+            root_id="1"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+  <!-- file -->
+  <projects long_name="org.foo.Bar" id="3" scope="FIL" qualifier="CLA" kee="project:org.foo.Bar"
+            name="Bar" root_id="[null]"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+
+  <!-- snapshots -->
+  <snapshots id="1000" project_id="1" parent_snapshot_id="[null]" root_project_id="1" root_snapshot_id="[null]"
+             scope="PRJ" qualifier="TRK" created_at="2008-11-01 13:58:00.00" version="[null]" path=""
+             status="P" islast="false" depth="0" />
+
+  <snapshots id="1001" project_id="2" parent_snapshot_id="1000" root_project_id="1" root_snapshot_id="1000"
+             scope="DIR" qualifier="PAC" created_at="2008-11-01 13:58:00.00" version="[null]" path="1000."
+             status="P" islast="false" depth="1" />
+
+  <snapshots id="1002" project_id="3" parent_snapshot_id="1001" root_project_id="1" root_snapshot_id="1000"
+             scope="FIL" qualifier="CLA" created_at="2008-11-01 13:58:00.00" version="[null]" path="1000.1001."
+             status="P" islast="false" depth="2" />
+
+
+  <!-- project measures -->
+  <project_measures id="1" VALUE="60" METRIC_ID="1" SNAPSHOT_ID="1000" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+
+  <project_measures id="2" VALUE="80" METRIC_ID="2" SNAPSHOT_ID="1000" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+
+  <!-- package measures -->
+  <project_measures id="3" VALUE="20" METRIC_ID="1" SNAPSHOT_ID="1001" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+
+  <project_measures id="4" VALUE="70" METRIC_ID="2" SNAPSHOT_ID="1001" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+
+  <!-- file measures -->
+  <project_measures id="5" VALUE="5" METRIC_ID="1" SNAPSHOT_ID="1002" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+
+  <project_measures id="6" VALUE="60" METRIC_ID="2" SNAPSHOT_ID="1002" alert_text="[null]" RULES_CATEGORY_ID="[null]"
+                    RULE_ID="[null]" text_value="[null]" tendency="[null]" measure_date="[null]" project_id="[null]"
+                    alert_status="[null]" description="[null]" rule_priority="[null]" characteristic_id="[null]" url="[null]"
+                    diff_value_1="[null]" diff_value_2="[null]" diff_value_3="[null]"/>
+</dataset>
\ No newline at end of file
diff --git a/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/PeriodLocatorTest/shouldLoadSnapshotsFromDatabase.xml b/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/PeriodLocatorTest/shouldLoadSnapshotsFromDatabase.xml
new file mode 100644
index 00000000000..6e5b5adfbfc
--- /dev/null
+++ b/plugins/sonar-core-plugin/src/test/resources/org/sonar/plugins/core/timemachine/PeriodLocatorTest/shouldLoadSnapshotsFromDatabase.xml
@@ -0,0 +1,76 @@
+<dataset>
+
+  <!-- project -->
+  <projects long_name="[null]" id="1" scope="PRJ" qualifier="TRK" kee="project" name="project"
+            root_id="[null]"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+  <!-- package -->
+  <projects long_name="[null]" id="2" scope="DIR" qualifier="PAC" kee="project:org.foo" name="org.foo"
+            root_id="1"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+  <!-- file -->
+  <projects long_name="org.foo.Bar" id="3" scope="FIL" qualifier="CLA" kee="project:org.foo.Bar"
+            name="Bar" root_id="[null]"
+            description="[null]"
+            enabled="true" language="java" copy_resource_id="[null]"/>
+
+
+  <!-- first analysis -->
+  <snapshots id="1000" project_id="1" parent_snapshot_id="[null]" root_project_id="1" root_snapshot_id="[null]"
+             scope="PRJ" qualifier="TRK" created_at="2008-11-01 13:58:00.00" version="[null]" path=""
+             status="P" islast="false" depth="0" />
+
+  <snapshots id="1001" project_id="2" parent_snapshot_id="1000" root_project_id="1" root_snapshot_id="1000"
+             scope="DIR" qualifier="PAC" created_at="2008-11-01 13:58:00.00" version="[null]" path="1000."
+             status="P" islast="false" depth="1" />
+
+  <snapshots id="1002" project_id="3" parent_snapshot_id="1001" root_project_id="1" root_snapshot_id="1000"
+             scope="FIL" qualifier="CLA" created_at="2008-11-01 13:58:00.00" version="[null]" path="1000.1001."
+             status="P" islast="false" depth="2" />
+
+
+  <!-- second analysis -->
+  <snapshots id="1003" project_id="1" parent_snapshot_id="[null]" root_project_id="1" root_snapshot_id="[null]"
+             scope="PRJ" qualifier="TRK" created_at="2008-11-02 13:58:00.00" version="[null]" path=""
+             status="P" islast="true" depth="0" />
+
+  <snapshots id="1004" project_id="2" parent_snapshot_id="1003" root_project_id="1" root_snapshot_id="1003"
+             scope="DIR" qualifier="PAC" created_at="2008-11-02 13:58:00.00" version="[null]" path="1003."
+             status="P" islast="true" depth="1" />
+
+  <snapshots id="1005" project_id="3" parent_snapshot_id="1004" root_project_id="1" root_snapshot_id="1003"
+             scope="FIL" qualifier="CLA" created_at="2008-11-02 13:58:00.00" version="[null]" path="1003.1004."
+             status="P" islast="true" depth="2" />
+
+
+  <!-- unprocessed analysis (to ignore) -->
+  <snapshots id="1006" project_id="1" parent_snapshot_id="[null]" root_project_id="1" root_snapshot_id="[null]"
+             scope="PRJ" qualifier="TRK" created_at="2008-11-03 13:58:00.00" version="[null]" path=""
+             status="U" islast="false" depth="0" />
+
+  <snapshots id="1007" project_id="2" parent_snapshot_id="1006" root_project_id="1" root_snapshot_id="1006"
+             scope="DIR" qualifier="PAC" created_at="2008-11-03 13:58:00.00" version="[null]" path="1006."
+             status="U" islast="false" depth="1" />
+
+  <snapshots id="1008" project_id="3" parent_snapshot_id="1007" root_project_id="1" root_snapshot_id="1006"
+             scope="FIL" qualifier="CLA" created_at="2008-11-03 13:58:00.00" version="[null]" path="1006.1007."
+             status="U" islast="false" depth="2" />
+
+
+  <!-- current analysis -->
+  <snapshots id="1009" project_id="1" parent_snapshot_id="[null]" root_project_id="1" root_snapshot_id="[null]"
+             scope="PRJ" qualifier="TRK" created_at="2008-11-04 13:58:00.00" version="[null]" path=""
+             status="U" islast="false" depth="0" />
+
+  <snapshots id="1010" project_id="2" parent_snapshot_id="1009" root_project_id="1" root_snapshot_id="1009"
+             scope="DIR" qualifier="PAC" created_at="2008-11-04 13:58:00.00" version="[null]" path="1009."
+             status="U" islast="false" depth="1" />
+
+  <snapshots id="1011" project_id="3" parent_snapshot_id="1010" root_project_id="1" root_snapshot_id="1009"
+             scope="FIL" qualifier="CLA" created_at="2008-11-04 13:58:00.00" version="[null]" path="1009.1010."
+             status="U" islast="false" depth="2" />
+</dataset>
\ No newline at end of file