Consistently declare Object::equals argument as @Nullable

spring-context/src/test/java/org/springframework/aop/framework/AbstractAopProxyTests.java

@@ -1651,7 +1651,7 @@ public abstract class AbstractAopProxyTests {
 	public static class AllInstancesAreEqual implements IOther {
 
 		@Override
-		public boolean equals(Object other) {
+		public boolean equals(@Nullable Object other) {
 			return (other instanceof AllInstancesAreEqual);
 		}
 

spring-context/src/test/java/org/springframework/aop/framework/CglibProxyTests.java

@@ -35,6 +35,7 @@ import org.springframework.beans.testfixture.beans.TestBean;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextException;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
+import org.springframework.lang.Nullable;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
@@ -214,7 +215,7 @@ public class CglibProxyTests extends AbstractAopProxyTests implements Serializab
 				return MethodMatcher.TRUE;
 			}
 			@Override
-			public boolean equals(Object obj) {
+			public boolean equals(@Nullable Object obj) {
 				return true;
 			}
 			@Override

spring-context/src/test/java/org/springframework/aop/framework/JdkDynamicProxyTests.java

@@ -27,6 +27,7 @@ import org.springframework.aop.support.AopUtils;
 import org.springframework.beans.testfixture.beans.IOther;
 import org.springframework.beans.testfixture.beans.ITestBean;
 import org.springframework.beans.testfixture.beans.TestBean;
+import org.springframework.lang.Nullable;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
@@ -197,7 +198,7 @@ public class JdkDynamicProxyTests extends AbstractAopProxyTests implements Seria
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o) {
 				return true;
 			}

spring-context/src/test/java/org/springframework/context/annotation/AnnotationConfigApplicationContextTests.java

@@ -37,6 +37,7 @@ import org.springframework.context.annotation6.Jsr330NamedForScanning;
 import org.springframework.context.testfixture.context.annotation.CglibConfiguration;
 import org.springframework.context.testfixture.context.annotation.LambdaBeanConfiguration;
 import org.springframework.core.ResolvableType;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 import static java.lang.String.format;
@@ -732,7 +733,7 @@ class TestBean {
 	}
 
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 		if (this == obj) {
 			return true;
 		}

spring-context/src/test/java/org/springframework/context/event/test/AbstractIdentifiable.java

@@ -18,6 +18,8 @@ package org.springframework.context.event.test;
 
 import java.util.UUID;
 
+import org.springframework.lang.Nullable;
+
 /**
  * @author Stephane Nicoll
  */
@@ -35,7 +37,7 @@ public abstract class AbstractIdentifiable implements Identifiable {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o) {
 			return true;
 		}

spring-context/src/test/java/org/springframework/context/event/test/GenericEventPojo.java

@@ -18,6 +18,7 @@ package org.springframework.context.event.test;
 
 import org.springframework.core.ResolvableType;
 import org.springframework.core.ResolvableTypeProvider;
+import org.springframework.lang.Nullable;
 
 /**
  * A simple POJO that implements {@link ResolvableTypeProvider}.
@@ -37,7 +38,7 @@ public class GenericEventPojo<T> implements ResolvableTypeProvider {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o) {
 			return true;
 		}

spring-context/src/test/java/org/springframework/context/event/test/IdentifiableApplicationEvent.java

@@ -19,6 +19,7 @@ package org.springframework.context.event.test;
 import java.util.UUID;
 
 import org.springframework.context.ApplicationEvent;
+import org.springframework.lang.Nullable;
 
 /**
  * A basic test event that can be uniquely identified easily.
@@ -49,7 +50,7 @@ public abstract class IdentifiableApplicationEvent extends ApplicationEvent impl
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o) {
 			return true;
 		}

spring-context/src/test/java/org/springframework/jmx/export/TestDynamicMBean.java

@@ -25,6 +25,8 @@ import javax.management.MBeanInfo;
 import javax.management.MBeanNotificationInfo;
 import javax.management.MBeanOperationInfo;
 
+import org.springframework.lang.Nullable;
+
 /**
  * @author Rob Harrop
  * @author Juergen Hoeller
@@ -76,7 +78,7 @@ public class TestDynamicMBean implements DynamicMBean {
 	}
 
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 		return (obj instanceof TestDynamicMBean);
 	}
 

spring-context/src/test/java/org/springframework/ui/ModelMapTests.java

@@ -29,6 +29,7 @@ import org.junit.jupiter.api.Test;
 
 import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.beans.testfixture.beans.TestBean;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
 
@@ -288,7 +289,7 @@ public class ModelMapTests {
 	public static class SomeInnerClass {
 
 		@Override
-		public boolean equals(Object obj) {
+		public boolean equals(@Nullable Object obj) {
 			return (obj instanceof SomeInnerClass);
 		}