Update FlatDataCollection API, modify Descriptives class to handle nu…

…lls.

CHANGELOG.md

@@ -1,10 +1,16 @@
 CHANGELOG
 =========
 
-Version 0.8.1-SNAPSHOT - Build 20170310
+Version 0.8.1-SNAPSHOT - Build 20170830
 ---------------------------------------
 
 - Updated the Maven Compiler, Nexus Staging, SLF4J and Logback Classic plugins to the latest stable versions. 
+- FlatDataColletion changes:
+	- The copyCollection2DoubleArray() and copyCollection2Array() methods are removed.
+	- It now implements the Collection Interface instead of the Iterable.
+- Descriptives class:
+	- New count() method returns the number of non-null elements.
+	- All methods can now handle null values. Null values are considered missing and they are ignored from the calculations.
 
 Version 0.8.0 - Build 20170114
 ------------------------------

README.md

@@ -27,7 +27,7 @@ The latest stable version of the framework is 0.8.0 (Build 20170114). To use it,
     </dependency>
 ```
 
-The latest snapshot version of the framework is 0.8.1-SNAPSHOT (Build 20170310). To test it, update your pom.xml as follows:
+The latest snapshot version of the framework is 0.8.1-SNAPSHOT (Build 20170830). To test it, update your pom.xml as follows:
 ```
     <repository>
        <id>sonatype-snapshots</id>

datumbox-framework-common/src/main/java/com/datumbox/framework/common/dataobjects/FlatDataCollection.java

@@ -15,7 +15,6 @@
  */
 package com.datumbox.framework.common.dataobjects;
 
-import java.lang.reflect.Array;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
@@ -29,45 +28,9 @@
  * 
  * @author Vasilis Vryniotis <bbriniotis@datumbox.com>
  */
-public class FlatDataCollection extends AbstractDataStructureCollection<Collection<Object>> implements Iterable<Object> {
+public class FlatDataCollection extends AbstractDataStructureCollection<Collection<Object>> implements Collection<Object> {
     private static final long serialVersionUID = 1L;
 
-    /**
-     * Converts to Object[] the original FlatDataCollection. The method is used to
-     * generate a copy of the flatDataCollection and it is called in order to
-     * avoid modifying the original array.
-     *
-     * @param <T>
-     * @param c
-     * @return
-     */
-    public final <T> T[] copyCollection2Array(Class<T> c) {
-        int n = internalData.size();
-        T[] copy = (T[]) Array.newInstance(c, n);
-        int i = 0;
-        for (Object value : internalData) {
-            copy[i++] = c.cast(value);
-        }
-        return copy;
-    }
-
-    /**
-     * Converts to Double[] safely the original FlatDataCollection by using the
-     * iteratorDouble.
-     *
-     * @return
-     */
-    public final Double[] copyCollection2DoubleArray() {
-        int n = internalData.size();
-        Double[] doubleArray = new Double[n];
-        int i = 0;
-        Iterator<Double> it = this.iteratorDouble();
-        while (it.hasNext()) {
-            doubleArray[i++] = it.next();
-        }
-        return doubleArray;
-    }
-
     /**
      * Public constructor which accepts as argument a Collection of Objects.
      * 
@@ -87,7 +50,31 @@ public FlatDataCollection(Collection<Object> internalData) {
     public final boolean remove(Object o) {
         return internalData.remove(o);
     }
-
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean containsAll(Collection<?> c) {
+        return internalData.containsAll(c);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean addAll(Collection<?> c) {
+        return internalData.addAll(c);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean removeAll(Collection<?> c) {
+        return internalData.removeAll(c);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean retainAll(Collection<?> c) {
+        return internalData.retainAll(c);
+    }
+
     /**
      * It adds an object in the collection. It returns a boolean which indicates 
      * whether the collection changed as a result of the call.
@@ -99,24 +86,18 @@ public final boolean add(Object e) {
         return internalData.add(e);
     }
 
-    /**
-     * Adds all the objects of the provided collection to the internal data. It 
-     * returns a boolean which indicates whether the collection changed as a 
-     * result of the call.
-     * 
-     * @param c
-     * @return 
-     */
-    public final boolean addAll(Collection<Object> c) {
-        return internalData.addAll(c);
-    }
-
     /** {@inheritDoc} */
     @Override
     public final Iterator<Object> iterator() {
         return internalData.iterator();
     }
-
+
+    /** {@inheritDoc} */
+    @Override
+    public <T> T[] toArray(T[] a) {
+        return internalData.toArray(a);
+    }
+
     /**
      * Converts the FlatDataCollection to a FlatDataList trying (if possible)
      * not to copy the data.