MATH-336 Unnecessary null checks in equals methods

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@922714 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/math/analysis/polynomials/PolynomialFunction.java

@@ -341,8 +341,6 @@ public class PolynomialFunction implements DifferentiableUnivariateRealFunction,
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
-        if (obj == null)
-            return false;
         if (!(obj instanceof PolynomialFunction))
             return false;
         PolynomialFunction other = (PolynomialFunction) obj;

src/main/java/org/apache/commons/math/linear/OpenMapRealVector.java

@@ -778,9 +778,6 @@ public class OpenMapRealVector extends AbstractRealVector implements SparseRealV
         if (this == obj) {
             return true;
         }
-        if (obj == null) {
-            return false;
-        }
         if (!(obj instanceof OpenMapRealVector)) {
             return false;
         }

src/main/java/org/apache/commons/math/linear/SparseFieldVector.java

@@ -615,10 +615,6 @@ public class SparseFieldVector<T extends FieldElement<T>> implements FieldVector
             return true;
         }
 
-        if (obj == null) {
-            return false;
-        }
-
         if (!(obj instanceof SparseFieldVector<?>)) {
             return false;
         }

src/main/java/org/apache/commons/math/stat/descriptive/moment/VectorialCovariance.java

@@ -135,8 +135,6 @@ public class VectorialCovariance implements Serializable {
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
-        if (obj == null)
-            return false;
         if (!(obj instanceof VectorialCovariance))
             return false;
         VectorialCovariance other = (VectorialCovariance) obj;

src/main/java/org/apache/commons/math/stat/descriptive/moment/VectorialMean.java

@@ -92,8 +92,6 @@ public class VectorialMean implements Serializable {
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
-        if (obj == null)
-            return false;
         if (!(obj instanceof VectorialMean))
             return false;
         VectorialMean other = (VectorialMean) obj;