SONAR-6939 ability for plugins to override the decimal scale of float

measures

19 files changed, 287 insertions, 675 deletions

diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaContext.java b/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaContext.java
index 766652028ed..50b1f151b7d 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaContext.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaContext.java
@@ -19,37 +19,42 @@
  */
 package org.sonar.api.batch;
 
+import org.sonar.api.measures.Formula;
 import org.sonar.api.measures.FormulaContext;
 import org.sonar.api.measures.Metric;
 import org.sonar.api.resources.Resource;
 
 /**
  * @since 1.11
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
+@Deprecated
 public class DefaultFormulaContext implements FormulaContext {
 
-  private Metric metric;
-  private DecoratorContext decoratorContext;
-
   public DefaultFormulaContext(Metric metric) {
-    this.metric = metric;
   }
 
   @Override
   public Metric getTargetMetric() {
-    return metric;
+    throw fail();
   }
 
   @Override
   public Resource getResource() {
-    return decoratorContext.getResource();
+    throw fail();
   }
 
   public void setMetric(Metric metric) {
-    this.metric = metric;
+    throw fail();
   }
 
   public void setDecoratorContext(DecoratorContext decoratorContext) {
-    this.decoratorContext = decoratorContext;
+    throw fail();
+  }
+
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaData.java b/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaData.java
index 1aa4bc24193..8e218a00c9c 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaData.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/batch/DefaultFormulaData.java
@@ -19,52 +19,51 @@
  */
 package org.sonar.api.batch;
 
+import java.util.Collection;
+import org.sonar.api.measures.Formula;
 import org.sonar.api.measures.FormulaData;
 import org.sonar.api.measures.Measure;
 import org.sonar.api.measures.MeasuresFilter;
 import org.sonar.api.measures.Metric;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-
 /**
  * @since 1.11
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
+@Deprecated
 public class DefaultFormulaData implements FormulaData {
 
-  private DecoratorContext decoratorContext;
-
-  public DefaultFormulaData(DecoratorContext decoratorContext) {
-    this.decoratorContext = decoratorContext;
+  public DefaultFormulaData(DecoratorContext unused) {
   }
 
   @Override
   public Measure getMeasure(Metric metric) {
-    return decoratorContext.getMeasure(metric);
+    throw fail();
   }
 
   @Override
   public <M> M getMeasures(MeasuresFilter<M> filter) {
-    return decoratorContext.getMeasures(filter);
+    throw fail();
   }
 
   @Override
   public Collection<Measure> getChildrenMeasures(MeasuresFilter filter) {
-    return decoratorContext.getChildrenMeasures(filter);
+    throw fail();
   }
 
   @Override
   public Collection<Measure> getChildrenMeasures(Metric metric) {
-    return decoratorContext.getChildrenMeasures(metric);
+    throw fail();
   }
 
   @Override
   public Collection<FormulaData> getChildren() {
-    List<FormulaData> result = new ArrayList<>();
-    for (DecoratorContext childContext : decoratorContext.getChildren()) {
-      result.add(new DefaultFormulaData(childContext));
-    }
-    return result;
+    throw fail();
+  }
+
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/AverageFormula.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/AverageFormula.java
index f029f438918..2c3af7f5b95 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/AverageFormula.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/AverageFormula.java
@@ -21,33 +21,15 @@
 package org.sonar.api.measures;
 
 import java.util.List;
-import org.sonar.api.resources.ResourceUtils;
-
-import static com.google.common.collect.Lists.newArrayList;
 
 /**
- * Formula used to compute an average for a given metric A, which is the result of the sum of measures of this metric (A) divided by another metric (B).
- * <p/>
- * For example: to compute the metric "complexity by file", the main metric (A) is "complexity" and the other metric (B) is "file".
- *
  * @since 3.0
- * @deprecated since 5.2 decorators are no more executed on batch side
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
 @Deprecated
 public class AverageFormula implements Formula {
 
-  private Metric mainMetric;
-  private Metric byMetric;
-  private Metric fallbackMetric;
-
-  /**
-   * This method should be private but it kep package-protected because of AverageComplexityFormula.
-   */
-  AverageFormula(Metric mainMetric, Metric byMetric) {
-    this.mainMetric = mainMetric;
-    this.byMetric = byMetric;
-  }
-
   /**
    * Creates a new {@link AverageFormula} class.
    *
@@ -55,7 +37,7 @@ public class AverageFormula implements Formula {
    * @param by   The metric used to divide the main metric to compute average (ex.: "file" for "complexity by file")
    */
   public static AverageFormula create(Metric main, Metric by) {
-    return new AverageFormula(main, by);
+    return new AverageFormula();
   }
 
   /**
@@ -65,8 +47,7 @@ public class AverageFormula implements Formula {
    * @since 3.6
    */
   public AverageFormula setFallbackForMainMetric(Metric fallbackMetric) {
-    this.fallbackMetric = fallbackMetric;
-    return this;
+    throw fail();
   }
 
   /**
@@ -74,7 +55,7 @@ public class AverageFormula implements Formula {
    */
   @Override
   public List<Metric> dependsUponMetrics() {
-    return fallbackMetric != null ? newArrayList(mainMetric, fallbackMetric, byMetric) : newArrayList(mainMetric, byMetric);
+    throw fail();
   }
 
   /**
@@ -82,56 +63,11 @@ public class AverageFormula implements Formula {
    */
   @Override
   public Measure calculate(FormulaData data, FormulaContext context) {
-    if (!shouldDecorateResource(data, context)) {
-      return null;
-    }
-
-    Measure result;
-    if (ResourceUtils.isFile(context.getResource())) {
-      result = calculateForFile(data, context);
-    } else {
-      result = calculateOnChildren(data, context);
-    }
-    return result;
-  }
-
-  private Measure calculateOnChildren(FormulaData data, FormulaContext context) {
-    Measure result = null;
-
-    double totalByMeasure = 0;
-    double totalMainMeasure = 0;
-    boolean hasApplicableChildren = false;
-
-    for (FormulaData childrenData : data.getChildren()) {
-      Double fallbackMeasure = fallbackMetric != null ? MeasureUtils.getValue(childrenData.getMeasure(fallbackMetric), null) : null;
-      Double childrenByMeasure = MeasureUtils.getValue(childrenData.getMeasure(byMetric), null);
-      Double childrenMainMeasure = MeasureUtils.getValue(childrenData.getMeasure(mainMetric), fallbackMeasure);
-      if (childrenMainMeasure != null && childrenByMeasure != null && childrenByMeasure > 0.0) {
-        totalByMeasure += childrenByMeasure;
-        totalMainMeasure += childrenMainMeasure;
-        hasApplicableChildren = true;
-      }
-    }
-    if (hasApplicableChildren) {
-      result = new Measure(context.getTargetMetric(), totalMainMeasure / totalByMeasure);
-    }
-    return result;
-  }
-
-  private Measure calculateForFile(FormulaData data, FormulaContext context) {
-    Measure result = null;
-
-    Double fallbackMeasure = fallbackMetric != null ? MeasureUtils.getValue(data.getMeasure(fallbackMetric), null) : null;
-    Double byMeasure = MeasureUtils.getValue(data.getMeasure(byMetric), null);
-    Double mainMeasure = MeasureUtils.getValue(data.getMeasure(mainMetric), fallbackMeasure);
-    if (mainMeasure != null && byMeasure != null && byMeasure > 0.0) {
-      result = new Measure(context.getTargetMetric(), mainMeasure / byMeasure);
-    }
-
-    return result;
+    throw fail();
   }
 
-  private static boolean shouldDecorateResource(FormulaData data, FormulaContext context) {
-    return !MeasureUtils.hasValue(data.getMeasure(context.getTargetMetric()));
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException("Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. " +
+      "Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaContext.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaContext.java
index b3c2fcb524b..2011af669f9 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaContext.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaContext.java
@@ -23,7 +23,10 @@ import org.sonar.api.resources.Resource;
 
 /**
  * @since 1.11
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
+@Deprecated
 public interface FormulaContext {
 
   Metric getTargetMetric();
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaData.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaData.java
index 8cf5bb54307..459aec61695 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaData.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/FormulaData.java
@@ -23,7 +23,10 @@ import java.util.Collection;
 
 /**
  * @since 1.11
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
+@Deprecated
 public interface FormulaData {
 
   Measure getMeasure(Metric metric);
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/MeanAggregationFormula.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/MeanAggregationFormula.java
index f66bf51009d..22647cca1d5 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/MeanAggregationFormula.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/MeanAggregationFormula.java
@@ -19,21 +19,17 @@
  */
 package org.sonar.api.measures;
 
-import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
 
 /**
  * @since 2.0
- * @deprecated since 5.2 decorators are no more executed on batch side
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
 @Deprecated
 public class MeanAggregationFormula implements Formula {
 
-  private boolean forceZeroIfMissingData=false;
-
-  public MeanAggregationFormula(boolean forceZeroIfMissingData) {
-    this.forceZeroIfMissingData = forceZeroIfMissingData;
+  public MeanAggregationFormula(boolean unused) {
   }
 
   public MeanAggregationFormula() {
@@ -42,26 +38,16 @@ public class MeanAggregationFormula implements Formula {
 
   @Override
   public List<Metric> dependsUponMetrics() {
-    return Collections.emptyList();
+    throw fail();
   }
 
   @Override
   public Measure calculate(FormulaData data, FormulaContext context) {
-    double sum=0.0;
-    int count=0;
-    boolean hasValue=false;
-    Collection<Measure> measures = data.getChildrenMeasures(context.getTargetMetric());
-    for (Measure measure : measures) {
-      if (MeasureUtils.hasValue(measure)) {
-        sum+=measure.getValue();
-        count++;
-        hasValue=true;
-      }
-    }
+    throw fail();
+  }
 
-    if (!hasValue && !forceZeroIfMissingData) {
-      return null;
-    }
-    return new Measure(context.getTargetMetric(), (count==0) ? 0.0 : (sum/count));
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/Measure.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/Measure.java
index 4f2bef50a9f..adeae251213 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/Measure.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/Measure.java
@@ -21,8 +21,6 @@ package org.sonar.api.measures;
 
 import com.google.common.annotations.Beta;
 import java.io.Serializable;
-import java.math.BigDecimal;
-import java.math.RoundingMode;
 import java.util.Date;
 import javax.annotation.CheckForNull;
 import javax.annotation.Nullable;
@@ -43,7 +41,9 @@ public class Measure<G extends Serializable> implements Serializable {
 
   /**
    * Default precision when saving a float type metric
+   * @deprecated in 5.3. Decimal scale is provided by metric, not by measure.
    */
+  @Deprecated
   public static final int DEFAULT_PRECISION = 1;
 
   protected String metricKey;
@@ -322,27 +322,22 @@ public class Measure<G extends Serializable> implements Serializable {
   /**
    * Sets the measure value with a given precision
    *
-   * @param v         the measure value
-   * @param precision the measure value precision
-   * @return the measure object instance
+   * @return {@code this}
+   * @deprecated in 5.3. The decimal scale is given by the metric, not by the measure. Anyway this parameter was enforced to 1 before version 5.3.
    */
-  public Measure<G> setValue(@Nullable Double v, int precision) {
+  @Deprecated
+  public Measure<G> setValue(@Nullable Double v, int decimalScale) {
     if (v != null) {
       if (Double.isNaN(v)) {
         throw new IllegalArgumentException("Measure value can not be NaN");
       }
-      this.value = scaleValue(v, precision);
+      this.value = v;
     } else {
       this.value = null;
     }
     return this;
   }
 
-  private static double scaleValue(double value, int scale) {
-    BigDecimal bd = BigDecimal.valueOf(value);
-    return bd.setScale(scale, RoundingMode.HALF_UP).doubleValue();
-  }
-
   /**
    * @return the data field of the measure
    */
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/Metric.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/Metric.java
index 949e0ab603c..8fdb94f44a6 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/Metric.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/Metric.java
@@ -27,19 +27,33 @@ import java.util.List;
 import javax.annotation.CheckForNull;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import org.apache.commons.lang.StringUtils;
 import org.apache.commons.lang.builder.ReflectionToStringBuilder;
 import org.apache.commons.lang.builder.ToStringStyle;
 import org.sonar.api.batch.BatchSide;
 import org.sonar.api.batch.InstantiationStrategy;
 import org.sonar.api.server.ServerSide;
 
+import static com.google.common.base.Objects.firstNonNull;
+import static com.google.common.base.Preconditions.checkArgument;
+import static org.apache.commons.lang.StringUtils.isNotBlank;
+
 @BatchSide
 @InstantiationStrategy(InstantiationStrategy.PER_BATCH)
 @ServerSide
 public class Metric<G extends Serializable> implements Serializable, org.sonar.api.batch.measure.Metric<G> {
 
   /**
+   * @since 5.3
+   */
+  public static final int DEFAULT_DECIMAL_SCALE = 1;
+
+  /**
+   * The maximum supported value of scale for decimal metrics
+   * @since 5.3
+   */
+  public static final int MAX_DECIMAL_SCALE = 20;
+
+  /**
    * A metric bigger value means a degradation
    */
   public static final int DIRECTION_WORST = -1;
@@ -126,6 +140,7 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
   private Boolean optimizedBestValue;
   private Boolean hidden = Boolean.FALSE;
   private Boolean deleteHistoricalData;
+  private Integer decimalScale;
 
   private Metric(Builder builder) {
     this.key = builder.key;
@@ -143,6 +158,7 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
     this.formula = builder.formula;
     this.userManaged = builder.userManaged;
     this.deleteHistoricalData = builder.deleteHistoricalData;
+    this.decimalScale = builder.decimalScale;
   }
 
   /**
@@ -208,9 +224,12 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
     this.name = name;
     this.qualitative = qualitative;
     this.userManaged = userManaged;
-    if (ValueType.PERCENT.equals(this.type)) {
+    if (ValueType.PERCENT == this.type) {
       this.bestValue = (direction == DIRECTION_BETTER) ? 100.0 : 0.0;
       this.worstValue = (direction == DIRECTION_BETTER) ? 0.0 : 100.0;
+      this.decimalScale = DEFAULT_DECIMAL_SCALE;
+    } else if (ValueType.FLOAT == this.type) {
+      this.decimalScale = DEFAULT_DECIMAL_SCALE;
     }
   }
 
@@ -492,6 +511,15 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
     return deleteHistoricalData;
   }
 
+  /**
+   * Return the number scale if metric type is {@link ValueType#FLOAT}, else {@code null}
+   * @since 5.3
+   */
+  @CheckForNull
+  public Integer getDecimalScale() {
+    return decimalScale;
+  }
+
   @Override
   public int hashCode() {
     return key.hashCode();
@@ -557,6 +585,7 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
     private boolean hidden = false;
     private boolean userManaged = false;
     private boolean deleteHistoricalData = false;
+    private Integer decimalScale = null;
 
     /**
      * Creates a new {@link Builder} object.
@@ -566,15 +595,9 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
      * @param type the metric type
      */
     public Builder(String key, String name, ValueType type) {
-      if (StringUtils.isBlank(key)) {
-        throw new IllegalArgumentException("Metric key can not be blank");
-      }
-      if (StringUtils.isBlank(name)) {
-        throw new IllegalArgumentException("Metric name can not be blank");
-      }
-      if (type == null) {
-        throw new IllegalArgumentException("Metric type can not be null");
-      }
+      checkArgument(isNotBlank(key), "Metric key can not be blank");
+      checkArgument(isNotBlank(name), "Name of metric %s must be set", key);
+      checkArgument(type != null, "Type of metric %s must be set", key);
       this.key = key;
       this.name = name;
       this.type = type;
@@ -647,11 +670,6 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
      * When a formula is set, sensors/decorators just need to store measures at a specific level and let Sonar run the formula to store
      * measures on the remaining levels.
      *
-     * @see SumChildDistributionFormula
-     * @see SumChildValuesFormula
-     * @see MeanAggregationFormula
-     * @see WeightedMeanAggregationFormula
-     *
      * @param f the formula
      * @return the builder
      *
@@ -741,14 +759,30 @@ public class Metric<G extends Serializable> implements Serializable, org.sonar.a
     }
 
     /**
+     * Scale to be used if the metric has decimal type ({@link ValueType#FLOAT} or {@link ValueType#PERCENT}).
+     * Default is 1. It is not set (({@code null}) on non-decimal metrics.
+     * @since 5.3
+     */
+    public Builder setDecimalScale(int scale) {
+      checkArgument(scale >= 0, "Scale of decimal metric %s must be positive: %d", key, scale);
+      checkArgument(scale <= MAX_DECIMAL_SCALE, "Scale of decimal metric [%s] must be less than or equal %s: %s", key, MAX_DECIMAL_SCALE, scale);
+      this.decimalScale = scale;
+      return this;
+    }
+
+    /**
      * Creates a new metric definition based on the properties set on this metric builder.
      *
      * @return a new {@link Metric} object
      */
     public <G extends Serializable> Metric<G> create() {
-      if (ValueType.PERCENT.equals(this.type)) {
+      if (ValueType.PERCENT == this.type) {
         this.bestValue = (direction == DIRECTION_BETTER) ? 100.0 : 0.0;
         this.worstValue = (direction == DIRECTION_BETTER) ? 0.0 : 100.0;
+        this.decimalScale = firstNonNull(decimalScale, DEFAULT_DECIMAL_SCALE);
+
+      } else if (ValueType.FLOAT == this.type) {
+        this.decimalScale = firstNonNull(decimalScale, DEFAULT_DECIMAL_SCALE);
       }
       return new Metric<>(this);
     }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildDistributionFormula.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildDistributionFormula.java
index e75a2f3c119..616eb2cbff7 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildDistributionFormula.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildDistributionFormula.java
@@ -19,50 +19,38 @@
  */
 package org.sonar.api.measures;
 
-import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
-import org.sonar.api.resources.Scopes;
 
 /**
  * @since 2.0
  *
  * Used to consolidate a distribution measure throughout the resource tree
- * @deprecated since 5.2 decorators are no more executed on batch side
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
 @Deprecated
 public class SumChildDistributionFormula implements Formula {
 
-  private String minimumScopeToPersist= Scopes.FILE;
-
   @Override
   public List<Metric> dependsUponMetrics() {
-    return Collections.emptyList();
+    throw fail();
   }
 
   public String getMinimumScopeToPersist() {
-    return minimumScopeToPersist;
+    throw fail();
   }
 
   public SumChildDistributionFormula setMinimumScopeToPersist(String s) {
-    this.minimumScopeToPersist = s;
-    return this;
+    throw fail();
   }
 
   @Override
   public Measure calculate(FormulaData data, FormulaContext context) {
-    Collection<Measure> measures = data.getChildrenMeasures(context.getTargetMetric());
-    if (measures == null || measures.isEmpty()) {
-      return null;
-    }
-    RangeDistributionBuilder distribution = new RangeDistributionBuilder(context.getTargetMetric());
-    for (Measure measure : measures) {
-      distribution.add(measure);
-    }
-    Measure measure = distribution.build();
-    if (!Scopes.isHigherThanOrEquals(context.getResource().getScope(), minimumScopeToPersist)) {
-      measure.setPersistenceMode(PersistenceMode.MEMORY);
-    }
-    return measure;
+    throw fail();
+  }
+
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildValuesFormula.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildValuesFormula.java
index 37e7abf6a25..450befdee5a 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildValuesFormula.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/SumChildValuesFormula.java
@@ -19,33 +19,31 @@
  */
 package org.sonar.api.measures;
 
-import java.util.Collections;
 import java.util.List;
 
 /**
  * @since 1.11
- * @deprecated since 5.2 decorators are no more executed on batch side
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
 @Deprecated
 public class SumChildValuesFormula implements Formula {
 
-  private boolean saveZeroIfNoChildValues;
-
-  public SumChildValuesFormula(boolean saveZeroIfNoChildValues) {
-    this.saveZeroIfNoChildValues = saveZeroIfNoChildValues;
+  public SumChildValuesFormula(boolean unused) {
   }
 
   @Override
   public List<Metric> dependsUponMetrics() {
-    return Collections.emptyList();
+    throw fail();
   }
 
   @Override
   public Measure calculate(FormulaData data, FormulaContext context) {
-    Double sum = MeasureUtils.sum(saveZeroIfNoChildValues, data.getChildrenMeasures(context.getTargetMetric()));
-    if (sum != null) {
-      return new Measure(context.getTargetMetric(), sum);
-    }
-    return null;
+    throw fail();
+  }
+
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/measures/WeightedMeanAggregationFormula.java b/sonar-plugin-api/src/main/java/org/sonar/api/measures/WeightedMeanAggregationFormula.java
index 7be604edaf6..360eb01ea9e 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/measures/WeightedMeanAggregationFormula.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/measures/WeightedMeanAggregationFormula.java
@@ -19,54 +19,31 @@
  */
 package org.sonar.api.measures;
 
-import java.util.Collections;
 import java.util.List;
 
 /**
  * @since 2.0
- * @deprecated since 5.2 decorators are no more executed on batch side
+ * @deprecated since 5.2. Aggregation of measures is provided by {@link org.sonar.api.ce.measure.MeasureComputer}. {@link org.sonar.api.batch.Decorator}
+ * and {@link Formula} are no more supported.
  */
 @Deprecated
 public class WeightedMeanAggregationFormula implements Formula {
 
-  private Metric weightingMetric;
-  private boolean zeroIfNoValues=false;
-
   public WeightedMeanAggregationFormula(Metric weightingMetric, boolean zeroIfNoValues) {
-    this.weightingMetric = weightingMetric;
-    if (weightingMetric==null) {
-      throw new IllegalArgumentException("Metric can not be null");
-    }
-    this.zeroIfNoValues = zeroIfNoValues;
   }
 
   @Override
   public List<Metric> dependsUponMetrics() {
-    return Collections.emptyList();
+    throw fail();
   }
 
   @Override
   public Measure calculate(FormulaData data, FormulaContext context) {
-    double sum=0.0;
-    double count=0.0;
-    boolean hasValue=false;
-
-    for (FormulaData child : data.getChildren()) {
-      Measure measure = child.getMeasure(context.getTargetMetric());
-      Measure weightingMeasure = child.getMeasure(weightingMetric);
-      if (MeasureUtils.haveValues(measure, weightingMeasure)) {
-        sum += measure.getValue() * weightingMeasure.getValue();
-        count += weightingMeasure.getValue();
-        hasValue=true;
-      }
-    }
-
-    if (!hasValue && !zeroIfNoValues) {
-      return null;
-    }
+    throw fail();
+  }
 
-    double result = (Double.doubleToRawLongBits(count)==0L) ? 0.0 : (sum/count);
-    return new Measure(context.getTargetMetric(), result);
+  private static RuntimeException fail() {
+    throw new UnsupportedOperationException(
+      "Unsupported since version 5.2. Decorators and formulas are not used anymore for aggregation measures. Please use org.sonar.api.ce.measure.MeasureComputer.");
   }
 }
-
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/batch/DefaultFormulaDataTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/batch/DefaultFormulaDataTest.java
index 5139aa75edb..03f6188eea6 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/batch/DefaultFormulaDataTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/batch/DefaultFormulaDataTest.java
@@ -23,42 +23,22 @@ import org.junit.Test;
 import org.sonar.api.measures.MeasuresFilter;
 import org.sonar.api.measures.Metric;
 
-import java.util.Arrays;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Matchers.any;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.when;
-
 public class DefaultFormulaDataTest {
 
-  @Test
-  public void isDecoratorContextProxy() {
-    DecoratorContext context = mock(DecoratorContext.class);
-    DefaultFormulaData data = new DefaultFormulaData(context);
-
-    data.getChildrenMeasures(any(MeasuresFilter.class));
-    verify(context).getChildrenMeasures(any(MeasuresFilter.class));
+  DefaultFormulaData underTest = new DefaultFormulaData(null);
 
-    data.getChildrenMeasures(any(Metric.class));
-    verify(context).getChildrenMeasures(any(Metric.class));
-
-    data.getMeasures(any(MeasuresFilter.class));
-    verify(context).getMeasures(any(MeasuresFilter.class));
-
-    data.getMeasure(any(Metric.class));
-    verify(context).getMeasure(any(Metric.class));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_1() {
+    underTest.getChildren();
   }
 
-  @Test
-  public void getChildren() {
-    DecoratorContext context = mock(DecoratorContext.class);
-    DecoratorContext child1 = mock(DecoratorContext.class);
-    DecoratorContext child2 = mock(DecoratorContext.class);
-    when(context.getChildren()).thenReturn(Arrays.asList(child1, child2));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_2() {
+    underTest.getChildrenMeasures((MeasuresFilter) null);
+  }
 
-    DefaultFormulaData data = new DefaultFormulaData(context);
-    assertThat(data.getChildren()).hasSize(2);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_3() {
+    underTest.getChildrenMeasures((Metric) null);
   }
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/AverageFormulaTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/AverageFormulaTest.java
index e4a9c96f57c..cc05ee44bbf 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/AverageFormulaTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/AverageFormulaTest.java
@@ -19,174 +19,24 @@
  */
 package org.sonar.api.measures;
 
-import org.junit.Before;
 import org.junit.Test;
-import org.sonar.api.resources.File;
-
-import java.util.List;
-
-import static com.google.common.collect.Lists.newArrayList;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
 
 public class AverageFormulaTest {
 
-  private FormulaContext context;
-  private FormulaData data;
+  AverageFormula underTest = new AverageFormula();
 
-  @Before
-  public void before() {
-    context = mock(FormulaContext.class);
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.FUNCTION_COMPLEXITY);
-    data = mock(FormulaData.class);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_1() {
+    underTest.calculate(null, null);
   }
 
-  @Test
-  public void test_depends_upon_metrics() throws Exception {
-    AverageFormula formula = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS);
-    assertThat(formula.dependsUponMetrics()).containsOnly(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_2() {
+    underTest.dependsUponMetrics();
   }
 
-  @Test
-  public void test_depends_upon_fallback_metric() throws Exception {
-    AverageFormula formula = AverageFormula.create(CoreMetrics.COMPLEXITY_IN_FUNCTIONS, CoreMetrics.FUNCTIONS).setFallbackForMainMetric(CoreMetrics.COMPLEXITY);
-    assertThat(formula.dependsUponMetrics()).containsOnly(CoreMetrics.COMPLEXITY_IN_FUNCTIONS, CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_3() {
+    underTest.setFallbackForMainMetric(null);
   }
-
-  @Test
-  public void test_average_calculation() {
-    List<FormulaData> childrenData = newArrayList();
-    FormulaData data1 = mock(FormulaData.class);
-    childrenData.add(data1);
-    when(data1.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 43.0));
-    when(data1.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 107.0));
-
-    FormulaData data2 = mock(FormulaData.class);
-    childrenData.add(data2);
-    when(data2.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 127.0));
-    when(data2.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 233.0));
-
-    when(data.getChildren()).thenReturn(childrenData);
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-
-    assertThat(measure.getValue()).isEqualTo(2.0);
-  }
-
-  @Test
-  public void should_not_compute_if_not_target_metric() {
-    when(data.getMeasure(CoreMetrics.FUNCTION_COMPLEXITY)).thenReturn(new Measure(CoreMetrics.FUNCTION_COMPLEXITY, 2.0));
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-    assertThat(measure).isNull();
-  }
-
-  @Test
-  public void test_when_no_children_measures() {
-    List<FormulaData> childrenData = newArrayList();
-    when(data.getChildren()).thenReturn(childrenData);
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-    assertThat(measure).isNull();
-  }
-
-  @Test
-  public void test_when_no_complexity_measures() {
-    List<FormulaData> childrenData = newArrayList();
-    FormulaData data1 = mock(FormulaData.class);
-    childrenData.add(data1);
-    when(data1.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 43.0));
-
-    when(data.getChildren()).thenReturn(childrenData);
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-
-    assertThat(measure).isNull();
-  }
-
-  @Test
-  public void test_when_no_by_metric_measures() {
-    List<FormulaData> childrenData = newArrayList();
-    FormulaData data1 = mock(FormulaData.class);
-    childrenData.add(data1);
-    when(data1.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 43.0));
-
-    when(data.getChildren()).thenReturn(childrenData);
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-
-    assertThat(measure).isNull();
-  }
-
-  @Test
-  public void test_when_mixed_metrics() {
-    List<FormulaData> childrenData = newArrayList();
-    FormulaData data1 = mock(FormulaData.class);
-    childrenData.add(data1);
-    when(data1.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 43.0));
-    when(data1.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 107.0));
-
-    FormulaData data2 = mock(FormulaData.class);
-    childrenData.add(data2);
-    when(data2.getMeasure(CoreMetrics.STATEMENTS)).thenReturn(new Measure(CoreMetrics.STATEMENTS, 127.0));
-    when(data2.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 233.0));
-
-    when(data.getChildren()).thenReturn(childrenData);
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-
-    assertThat(measure.getValue()).isEqualTo(2.5);
-  }
-
-  @Test
-  public void test_calculation_for_file() {
-    when(data.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 60.0));
-    when(data.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 20.0));
-    when(context.getResource()).thenReturn(File.create("foo"));
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY, CoreMetrics.FUNCTIONS).calculate(data, context);
-    assertThat(measure.getValue()).isEqualTo(3.0);
-  }
-
-  @Test
-  public void should_use_fallback_metric_when_no_data_on_main_metric_for_file() {
-    when(data.getMeasure(CoreMetrics.COMPLEXITY_IN_FUNCTIONS)).thenReturn(null);
-    when(data.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 60.0));
-    when(data.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 20.0));
-    when(context.getResource()).thenReturn(File.create("foo"));
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY_IN_FUNCTIONS, CoreMetrics.FUNCTIONS)
-      .setFallbackForMainMetric(CoreMetrics.COMPLEXITY)
-      .calculate(data, context);
-    assertThat(measure.getValue()).isEqualTo(3.0);
-  }
-
-  @Test
-  public void should_use_main_metric_even_if_fallback_metric_provided() {
-    when(data.getMeasure(CoreMetrics.COMPLEXITY_IN_FUNCTIONS)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 60.0));
-    when(data.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 42.0));
-    when(data.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 20.0));
-    when(context.getResource()).thenReturn(File.create("foo"));
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY_IN_FUNCTIONS, CoreMetrics.FUNCTIONS)
-      .setFallbackForMainMetric(CoreMetrics.COMPLEXITY)
-      .calculate(data, context);
-    assertThat(measure.getValue()).isEqualTo(3.0);
-  }
-
-  @Test
-  public void should_use_fallback_metric_when_no_data_on_main_metric_for_children() {
-    List<FormulaData> childrenData = newArrayList();
-    FormulaData data1 = mock(FormulaData.class);
-    childrenData.add(data1);
-    when(data1.getMeasure(CoreMetrics.COMPLEXITY_IN_FUNCTIONS)).thenReturn(null);
-    when(data1.getMeasure(CoreMetrics.COMPLEXITY)).thenReturn(new Measure(CoreMetrics.COMPLEXITY, 107.0));
-    when(data1.getMeasure(CoreMetrics.FUNCTIONS)).thenReturn(new Measure(CoreMetrics.FUNCTIONS, 43.0));
-
-    when(data.getChildren()).thenReturn(childrenData);
-
-    Measure measure = AverageFormula.create(CoreMetrics.COMPLEXITY_IN_FUNCTIONS, CoreMetrics.FUNCTIONS)
-      .setFallbackForMainMetric(CoreMetrics.COMPLEXITY)
-      .calculate(data, context);
-
-    assertThat(measure.getValue()).isEqualTo(2.5);
-  }
-
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeanAggregationFormulaTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeanAggregationFormulaTest.java
index c1443832c7b..2beec78cdd1 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeanAggregationFormulaTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeanAggregationFormulaTest.java
@@ -19,57 +19,19 @@
  */
 package org.sonar.api.measures;
 
-import org.junit.Before;
 import org.junit.Test;
 
-import java.util.Arrays;
-import java.util.Collections;
-
-import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertThat;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
-
 public class MeanAggregationFormulaTest {
 
-  private FormulaContext context;
-  private FormulaData data;
-
-  @Before
-  public void before() {
-    context = mock(FormulaContext.class);
-    data = mock(FormulaData.class);
-  }
-
-  @Test
-  public void calculateChildrenMean() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.COVERAGE);
-    when(data.getChildrenMeasures(CoreMetrics.COVERAGE)).thenReturn(Arrays.<Measure>asList(newCoverage(100.0), newCoverage(50.0), newCoverage(30.0)));
-
-    Measure measure = new MeanAggregationFormula().calculate(data, context);
-    assertThat(measure.getValue(), is(60.0));
-  }
-
-  @Test
-  public void doNotForceZero() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.COVERAGE);
-    when(data.getChildrenMeasures(CoreMetrics.COVERAGE)).thenReturn(Collections.<Measure>emptyList());
-
-    Measure measure = new MeanAggregationFormula(false).calculate(data, context);
-    assertNull(measure);
-  }
-
-  @Test
-  public void forceZero() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.COVERAGE);
-    when(data.getChildrenMeasures(CoreMetrics.COVERAGE)).thenReturn(Collections.<Measure>emptyList());
+  MeanAggregationFormula underTest = new MeanAggregationFormula();
 
-    Measure measure = new MeanAggregationFormula(true).calculate(data, context);
-    assertThat(measure.getValue(), is(0.0));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_1() {
+    underTest.calculate(null, null);
   }
 
-  private Measure newCoverage(double val) {
-    return new Measure(CoreMetrics.COVERAGE, val);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_2() {
+    underTest.dependsUponMetrics();
   }
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeasureTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeasureTest.java
index 9a33b01caab..b671a63e9c7 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeasureTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MeasureTest.java
@@ -46,12 +46,6 @@ public class MeasureTest {
   }
 
   @Test
-  public void scaleValue() {
-    assertThat(new Measure(CoreMetrics.COVERAGE, 80.666666).getValue()).isEqualTo(80.7);
-    assertThat(new Measure(CoreMetrics.COVERAGE, 80.666666, 2).getValue()).isEqualTo(80.67);
-  }
-
-  @Test
   public void defaultPersistenceModeIsFull() {
     assertThat(new Measure(CoreMetrics.LINES, 32.0).getPersistenceMode()).isEqualTo(PersistenceMode.FULL);
   }
@@ -81,15 +75,6 @@ public class MeasureTest {
     assertThat(new Measure(CoreMetrics.LINES).setValue(3.6).getIntValue()).isEqualTo(3);
   }
 
-  @Test
-  public void valuesAreRoundUp() {
-    assertThat(new Measure(CoreMetrics.COVERAGE, 5.22222222).getValue()).isEqualTo(5.2);
-    assertThat(new Measure(CoreMetrics.COVERAGE, 5.7777777).getValue()).isEqualTo(5.8);
-
-    assertThat(new Measure(CoreMetrics.COVERAGE, 5.22222222, 3).getValue()).isEqualTo(5.222);
-    assertThat(new Measure(CoreMetrics.COVERAGE, 5.7777777, 3).getValue()).isEqualTo(5.778);
-  }
-
   /**
    * Proper definition of equality for measures is important, because used to store them.
    */
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MetricTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MetricTest.java
index 24ae4b69be7..0a088f53d3a 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/MetricTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/MetricTest.java
@@ -19,55 +19,97 @@
  */
 package org.sonar.api.measures;
 
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
 
-import static org.hamcrest.core.Is.is;
-import static org.hamcrest.core.IsNull.nullValue;
-import static org.junit.Assert.assertThat;
+import static org.assertj.core.api.Assertions.assertThat;
 
 public class MetricTest {
 
+  @Rule
+  public ExpectedException expectedException = ExpectedException.none();
+
   @Test
   public void shouldCreateMetric() {
     Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.INT)
-        .setDomain("my domain")
-        .create();
+      .setDomain("my domain")
+      .create();
 
-    assertThat(metric.getKey(), is("foo"));
-    assertThat(metric.getName(), is("Foo"));
-    assertThat(metric.getDomain(), is("my domain"));
+    assertThat(metric.getKey()).isEqualTo("foo");
+    assertThat(metric.getName()).isEqualTo("Foo");
+    assertThat(metric.getDomain()).isEqualTo("my domain");
   }
 
   @Test
   public void shouldCreateMetricWithDefaultValues() {
     Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.INT)
-        .create();
-
-    assertThat(metric.getBestValue(), nullValue());
-    assertThat(metric.getDescription(), nullValue());
-    assertThat(metric.getWorstValue(), nullValue());
-    assertThat(metric.getDirection(), is(Metric.DIRECTION_NONE));
-    assertThat(metric.getEnabled(), is(true));
-    assertThat(metric.getFormula(), nullValue());
-    assertThat(metric.getId(), nullValue());
-    assertThat(metric.getUserManaged(), is(false));
-    assertThat(metric.isHidden(), is(false));
-    assertThat(metric.isOptimizedBestValue(), is(false));
+      .create();
+
+    assertThat(metric.getBestValue()).isNull();
+    assertThat(metric.getDescription()).isNull();
+    assertThat(metric.getWorstValue()).isNull();
+    assertThat(metric.getDirection()).isEqualTo(Metric.DIRECTION_NONE);
+    assertThat(metric.getEnabled()).isTrue();
+    assertThat(metric.getFormula()).isNull();
+    assertThat(metric.getId()).isNull();
+    assertThat(metric.getUserManaged()).isFalse();
+    assertThat(metric.isHidden()).isFalse();
+    assertThat(metric.isOptimizedBestValue()).isFalse();
   }
 
   @Test
   public void shouldCreatePercentMetricWithDefaultValues() {
     Metric better = new Metric.Builder("foo", "Foo", Metric.ValueType.PERCENT)
-        .setDirection(Metric.DIRECTION_BETTER)
-        .create();
+      .setDirection(Metric.DIRECTION_BETTER)
+      .create();
     Metric worst = new Metric.Builder("foo", "Foo", Metric.ValueType.PERCENT)
-        .setDirection(Metric.DIRECTION_WORST)
-        .create();
+      .setDirection(Metric.DIRECTION_WORST)
+      .create();
+
+    assertThat(better.getBestValue()).isEqualTo(100.0);
+    assertThat(better.getWorstValue()).isEqualTo(0.0);
+    assertThat(worst.getBestValue()).isEqualTo(0.0);
+    assertThat(worst.getWorstValue()).isEqualTo(100.0);
+  }
+
+  @Test
+  public void override_decimal_scale_of_float_metric() {
+    Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.FLOAT)
+      .setDecimalScale(3)
+      .create();
+    assertThat(metric.getDecimalScale()).isEqualTo(3);
+  }
+
+  @Test
+  public void fail_if_decimal_scale_is_greater_than_max_supported_value() {
+    expectedException.expect(IllegalArgumentException.class);
+    expectedException.expectMessage("Scale of decimal metric [foo] must be less than or equal 20: 21");
 
-    assertThat(better.getBestValue(), is(100.0));
-    assertThat(better.getWorstValue(), is(0.0));
-    assertThat(worst.getBestValue(), is(0.0));
-    assertThat(worst.getWorstValue(), is(100.0));
+    new Metric.Builder("foo", "Foo", Metric.ValueType.FLOAT)
+      .setDecimalScale(Metric.MAX_DECIMAL_SCALE + 1)
+      .create();
   }
 
+  @Test
+  public void override_decimal_scale_of_percent_metric() {
+    Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.PERCENT)
+      .setDecimalScale(3)
+      .create();
+    assertThat(metric.getDecimalScale()).isEqualTo(3);
+  }
+
+  @Test
+  public void default_decimal_scale_is_1() {
+    Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.FLOAT)
+      .create();
+    assertThat(metric.getDecimalScale()).isEqualTo(1);
+  }
+
+  @Test
+  public void non_decimal_metric_has_no_scale() {
+    Metric metric = new Metric.Builder("foo", "Foo", Metric.ValueType.INT)
+      .create();
+    assertThat(metric.getDecimalScale()).isNull();
+  }
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildDistributionFormulaTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildDistributionFormulaTest.java
index b4d64fd8551..e712da3f312 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildDistributionFormulaTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildDistributionFormulaTest.java
@@ -19,122 +19,29 @@
  */
 package org.sonar.api.measures;
 
-import com.google.common.collect.Lists;
-import org.junit.Before;
 import org.junit.Test;
-import org.sonar.api.resources.Directory;
-import org.sonar.api.resources.File;
-import org.sonar.api.resources.Scopes;
-
-import java.util.Collections;
-import java.util.List;
-
-import static junit.framework.Assert.assertNull;
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.is;
-import static org.hamcrest.Matchers.nullValue;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
 
 public class SumChildDistributionFormulaTest {
-  SumChildDistributionFormula formula;
-  FormulaContext context;
-  FormulaData data;
-
-  @Before
-  public void init() {
-    formula = new SumChildDistributionFormula();
-    context = mock(FormulaContext.class);
-    when(context.getResource()).thenReturn(File.create("foo"));
-    data = mock(FormulaData.class);
-  }
-
-  @Test
-  public void testWhenGetChildrenReturnsNull() {
-    when(context.getTargetMetric()).thenReturn(new Metric("foo"));
-    when(data.getChildrenMeasures(new Metric("foo"))).thenReturn(null);
-    assertNull(formula.calculate(data, context));
-  }
-
-  @Test
-  public void testWhenGetChildrenReturnsEmpty() {
-    when(context.getTargetMetric()).thenReturn(new Metric("foo"));
-    when(data.getChildrenMeasures(new Metric("foo"))).thenReturn(Collections.<Measure>emptyList());
-    assertNull(formula.calculate(data, context));
-  }
-
-  @Test
-  public void shouldNotSumDifferentRanges() {
-    Metric m = new Metric("foo", Metric.ValueType.DATA);
-    when(context.getTargetMetric()).thenReturn(m);
-
-    List<Measure> list = Lists.newArrayList(
-      new Measure(m, "1=0;2=2;5=0;10=10;20=2"),
-      new Measure(m, "1=0;2=2;5=0;10=10;30=3")
-      );
-    when(data.getChildrenMeasures(new Metric("foo"))).thenReturn(list);
-    assertThat(formula.calculate(data, context), nullValue());
-  }
 
-  @Test
-  public void shouldSumSameIntRanges() {
-    Metric m = new Metric("foo", Metric.ValueType.DATA);
-    when(context.getTargetMetric()).thenReturn(m);
+  SumChildDistributionFormula underTest = new SumChildDistributionFormula();
 
-    List<Measure> list = Lists.newArrayList(
-      new Measure(m, "1=0;2=2;5=0;10=10;20=2"),
-      new Measure(m, "1=3;2=2;5=3;10=12;20=0")
-      );
-    when(data.getChildrenMeasures(new Metric("foo"))).thenReturn(list);
-    assertThat(formula.calculate(data, context).getData(), is("1=3;2=4;5=3;10=22;20=2"));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_1() {
+    underTest.calculate(null, null);
   }
 
-  @Test
-  public void shouldSumSameDoubleRanges() {
-    initContextWithChildren();
-    assertThat(formula.calculate(data, context).getData(), is("0.5=3;2.5=6"));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_2() {
+    underTest.dependsUponMetrics();
   }
 
-  @Test
-  public void shouldNotPersistWhenScopeLowerThanMinimun() {
-    when(context.getResource()).thenReturn(File.create("org/Foo.java"));
-
-    initContextWithChildren();
-    formula.setMinimumScopeToPersist(Scopes.DIRECTORY);
-
-    Measure distribution = formula.calculate(data, context);
-    assertThat(distribution.getPersistenceMode().useDatabase(), is(false));
-  }
-
-  @Test
-  public void shouldPersistWhenScopeEqualsMinimun() {
-    when(context.getResource()).thenReturn(File.create("org/Foo.java"));
-
-    initContextWithChildren();
-    formula.setMinimumScopeToPersist(Scopes.FILE);
-
-    Measure distribution = formula.calculate(data, context);
-    assertThat(distribution.getPersistenceMode().useDatabase(), is(true));
-  }
-
-  @Test
-  public void shouldPersistWhenScopeHigherThanMinimun() {
-    when(context.getResource()).thenReturn(Directory.create("org/foo"));
-
-    initContextWithChildren();
-    formula.setMinimumScopeToPersist(Scopes.FILE);
-
-    Measure distribution = formula.calculate(data, context);
-    assertThat(distribution.getPersistenceMode().useDatabase(), is(true));
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_3() {
+    underTest.getMinimumScopeToPersist();
   }
 
-  private void initContextWithChildren() {
-    Metric m = new Metric("foo", Metric.ValueType.DATA);
-    when(context.getTargetMetric()).thenReturn(m);
-    List<Measure> list = Lists.newArrayList(
-      new Measure(m, "0.5=0;2.5=2"),
-      new Measure(m, "0.5=3;2.5=4")
-      );
-    when(data.getChildrenMeasures(new Metric("foo"))).thenReturn(list);
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_4() {
+    underTest.setMinimumScopeToPersist(null);
   }
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildValuesFormulaTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildValuesFormulaTest.java
deleted file mode 100644
index 5bc69ab6684..00000000000
--- a/sonar-plugin-api/src/test/java/org/sonar/api/measures/SumChildValuesFormulaTest.java
+++ /dev/null
@@ -1,74 +0,0 @@
-/*
- * SonarQube, open source software quality management tool.
- * Copyright (C) 2008-2014 SonarSource
- * mailto:contact AT sonarsource DOT com
- *
- * SonarQube 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.
- *
- * SonarQube 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 this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
- */
-package org.sonar.api.measures;
-
-import org.junit.Before;
-import org.junit.Test;
-
-import java.util.Arrays;
-import java.util.Collections;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
-
-public class SumChildValuesFormulaTest {
-  private FormulaContext context;
-  private FormulaData data;
-
-  @Before
-  public void before() {
-    context = mock(FormulaContext.class);
-    data = mock(FormulaData.class);
-  }
-
-  @Test
-  public void sumChildValues() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.NCLOC);
-    when(data.getChildrenMeasures(CoreMetrics.NCLOC)).thenReturn(
-      Arrays.<Measure>asList(new Measure(CoreMetrics.NCLOC, 100.0), new Measure(CoreMetrics.NCLOC, 50.0)));
-
-    Measure measure = new SumChildValuesFormula(true).calculate(data, context);
-
-    assertThat(measure.getMetric()).isEqualTo(CoreMetrics.NCLOC);
-    assertThat(measure.getValue()).isEqualTo(150.0);
-  }
-
-  @Test
-  public void doNotInsertZero() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.NCLOC);
-    when(data.getChildrenMeasures(CoreMetrics.NCLOC)).thenReturn(Collections.<Measure>emptyList());
-
-    Measure measure = new SumChildValuesFormula(false).calculate(data, context);
-
-    assertThat(measure).isNull();
-  }
-
-  @Test
-  public void doInsertZero() {
-    when(context.getTargetMetric()).thenReturn(CoreMetrics.NCLOC);
-    when(data.getChildrenMeasures(CoreMetrics.NCLOC)).thenReturn(Collections.<Measure>emptyList());
-
-    Measure measure = new SumChildValuesFormula(true).calculate(data, context);
-
-    assertThat(measure.getMetric()).isEqualTo(CoreMetrics.NCLOC);
-    assertThat(measure.getValue()).isEqualTo(0.0);
-  }
-}
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/measures/WeightedMeanAggregationFormulaTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/measures/WeightedMeanAggregationFormulaTest.java
new file mode 100644
index 00000000000..3aa8d6d50af
--- /dev/null
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/measures/WeightedMeanAggregationFormulaTest.java
@@ -0,0 +1,36 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube 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.
+ *
+ * SonarQube 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 this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.api.measures;
+
+import org.junit.Test;
+
+public class WeightedMeanAggregationFormulaTest {
+  WeightedMeanAggregationFormula underTest = new WeightedMeanAggregationFormula(null, false);
+
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_1() {
+    underTest.calculate(null, null);
+  }
+
+  @Test(expected = UnsupportedOperationException.class)
+  public void fail_if_used_2() {
+    underTest.dependsUponMetrics();
+  }
+}