sonar clean up suggestions

src/main/java/com/xeiam/xchart/AxisTick.java

@@ -156,15 +156,15 @@ public class AxisTick implements IChartPart, IHideable {
       tickLocations.add((int) (margin + tickSpace / 2.0));
     } else {
 
-      final BigDecimal MIN = new BigDecimal(axis.min.doubleValue());
+      final BigDecimal min = new BigDecimal(axis.min.doubleValue());
       BigDecimal firstPosition;
       BigDecimal gridStep = getGridStep(tickSpace);
 
-      double xyz = MIN.remainder(gridStep).doubleValue();
+      double xyz = min.remainder(gridStep).doubleValue();
       if (xyz <= 0.0) {
-        firstPosition = MIN.subtract(MIN.remainder(gridStep));
+        firstPosition = min.subtract(min.remainder(gridStep));
       } else {
-        firstPosition = MIN.subtract(MIN.remainder(gridStep)).add(gridStep);
+        firstPosition = min.subtract(min.remainder(gridStep)).add(gridStep);
       }
 
       for (BigDecimal b = firstPosition; b.compareTo(axis.max) <= 0; b = b.add(gridStep)) {

src/main/java/com/xeiam/xchart/ChartLegend.java

@@ -32,7 +32,7 @@ import com.xeiam.xchart.series.markers.Marker;
  */
 public class ChartLegend implements IHideable {
 
-  private final int LEGEND_PADDING = 10;
+  private static final int LEGEND_PADDING = 10;
 
   /** parent */
   private Chart chart;

src/main/java/com/xeiam/xchart/interfaces/IChartPart.java

@@ -19,6 +19,8 @@ import java.awt.Graphics2D;
 import java.awt.Rectangle;
 
 /**
+ * All components of a chart that need to be painted should implement this interface
+ * 
  * @author timmolter
  */
 public interface IChartPart {

src/main/java/com/xeiam/xchart/interfaces/IHideable.java

@@ -7,7 +7,7 @@
 package com.xeiam.xchart.interfaces;
 
 /**
- * Chart Legend interface
+ * ChartParts that can be set visible or not should implement this interface
  * 
  * @author timmolter
  */

src/main/java/com/xeiam/xchart/series/Series.java

@@ -65,10 +65,12 @@ public class Series {
   /**
    * Constructor
    * 
-   * @param <?>
    * @param name
    * @param xData
+   * @param xAxisType
    * @param yData
+   * @param yAxisType
+   * @param errorBars
    */
   public Series(String name, Collection<?> xData, AxisType xAxisType, Collection<Number> yData, AxisType yAxisType, Collection<Number> errorBars) {