Add Nullable annotation to parameter of overridden equals method.

Closes: #4226
Original pull request: #4277

Author: christophstrobl

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ChangeStreamEvent.java

@@ -199,7 +199,7 @@ public String toString() {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 
 		if (this == o)
 			return true;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ChangeStreamOptions.java

@@ -153,7 +153,7 @@ private static <T> Object doGetTimestamp(Object timestamp, Class<T> targetType)
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/DefaultBulkOperations.java

@@ -598,7 +598,7 @@ public EntityCallbacks getEntityCallbacks() {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o)
 				return true;
 			if (o == null || getClass() != o.getClass())
@@ -667,7 +667,7 @@ public WriteModel<Document> getModel() {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o)
 				return true;
 			if (o == null || getClass() != o.getClass())

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/MongoDatabaseFactorySupport.java

@@ -269,7 +269,7 @@ public MongoDatabaseFactory getDelegate() {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o)
 				return true;
 			if (o == null || getClass() != o.getClass())

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/SimpleReactiveMongoDatabaseFactory.java

@@ -283,7 +283,7 @@ public ReactiveMongoDatabaseFactory getDelegate() {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o)
 				return true;
 			if (o == null || getClass() != o.getClass())

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/ExposedFields.java

@@ -318,7 +318,7 @@ public String toString() {
 		 * @see java.lang.Object#equals(java.lang.Object)
 		 */
 		@Override
-		public boolean equals(Object obj) {
+		public boolean equals(@Nullable Object obj) {
 
 			if (this == obj) {
 				return true;
@@ -431,7 +431,7 @@ public String toString() {
 		 * @see java.lang.Object#equals(java.lang.Object)
 		 */
 		@Override
-		public boolean equals(Object obj) {
+		public boolean equals(@Nullable Object obj) {
 
 			if (this == obj) {
 				return true;
@@ -510,7 +510,7 @@ public String toString() {
 		}
 
 		@Override
-		public boolean equals(Object obj) {
+		public boolean equals(@Nullable Object obj) {
 
 			if (this == obj) {
 				return true;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/Fields.java

@@ -326,7 +326,7 @@ public String toString() {
 		 * @see java.lang.Object#equals(java.lang.Object)
 		 */
 		@Override
-		public boolean equals(Object obj) {
+		public boolean equals(@Nullable Object obj) {
 
 			if (this == obj) {
 				return true;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/geo/GeoJsonGeometryCollection.java

@@ -19,6 +19,7 @@
 import java.util.Collections;
 import java.util.List;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -79,7 +80,7 @@ public int hashCode() {
 	 * @see java.lang.Object#equals(java.lang.Object)
 	 */
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 
 		if (this == obj) {
 			return true;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/geo/GeoJsonMultiLineString.java

@@ -20,6 +20,7 @@
 import java.util.List;
 
 import org.springframework.data.geo.Point;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -94,7 +95,7 @@ public int hashCode() {
 	 * @see java.lang.Object#equals(java.lang.Object)
 	 */
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 
 		if (this == obj) {
 			return true;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/geo/GeoJsonMultiPoint.java

@@ -21,6 +21,7 @@
 import java.util.List;
 
 import org.springframework.data.geo.Point;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -116,7 +117,7 @@ public int hashCode() {
 	 * @see java.lang.Object#equals(java.lang.Object)
 	 */
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 
 		if (this == obj) {
 			return true;