Replace isAssignableFrom() with isInstance() where feasible

Closes gh-36899

Signed-off-by: Yanming Zhou <zhouyanming@gmail.com>

Author: quaff

framework-docs/modules/ROOT/pages/integration/jmx/notifications.adoc

@@ -32,7 +32,7 @@ example writes notifications to the console:
 		}
 
 		public boolean isNotificationEnabled(Notification notification) {
-			return AttributeChangeNotification.class.isAssignableFrom(notification.getClass());
+			return (notification instanceof AttributeChangeNotification);
 		}
 
 	}

spring-aop/src/main/java/org/springframework/aop/aspectj/AspectJAfterThrowingAdvice.java

@@ -75,7 +75,7 @@ public void setThrowingName(String name) {
 	 * is only invoked if the thrown exception is a subtype of the given throwing type.
 	 */
 	private boolean shouldInvokeOnThrowing(Throwable ex) {
-		return getDiscoveredThrowingType().isAssignableFrom(ex.getClass());
+		return getDiscoveredThrowingType().isInstance(ex);
 	}
 
 }

spring-beans/src/main/java/org/springframework/beans/factory/support/SimpleInstantiationStrategy.java

@@ -159,7 +159,7 @@ public Object instantiate(RootBeanDefinition bd, @Nullable String beanName, Bean
 				return result;
 			}
 			catch (IllegalArgumentException ex) {
-				if (factoryBean != null && !factoryMethod.getDeclaringClass().isAssignableFrom(factoryBean.getClass())) {
+				if (factoryBean != null && !factoryMethod.getDeclaringClass().isInstance(factoryBean)) {
 					throw new BeanInstantiationException(factoryMethod,
 							"Illegal factory instance for factory method '" + factoryMethod.getName() + "'; " +
 									"instance: " + factoryBean.getClass().getName(), ex);

spring-context/src/main/java/org/springframework/context/annotation/ComponentScanBeanDefinitionParser.java

@@ -276,7 +276,7 @@ private Object instantiateUserDefinedStrategy(
 					strategyType.getName() + "]: a zero-argument constructor is required", ex);
 		}
 
-		if (!strategyType.isAssignableFrom(result.getClass())) {
+		if (!strategyType.isInstance(result)) {
 			throw new IllegalArgumentException("Provided class name must be an implementation of " + strategyType);
 		}
 		return result;

spring-core/src/main/java/org/springframework/util/ReflectionUtils.java

@@ -768,7 +768,7 @@ private static Field[] getDeclaredFields(Class<?> clazz) {
 	public static void shallowCopyFieldState(final Object src, final Object dest) {
 		Assert.notNull(src, "Source for field copy cannot be null");
 		Assert.notNull(dest, "Destination for field copy cannot be null");
-		if (!src.getClass().isAssignableFrom(dest.getClass())) {
+		if (!src.getClass().isInstance(dest)) {
 			throw new IllegalArgumentException("Destination class [" + dest.getClass().getName() +
 					"] must be same or subclass as source class [" + src.getClass().getName() + "]");
 		}

spring-expression/src/main/java/org/springframework/expression/spel/ast/OperatorInstanceof.java

@@ -72,7 +72,7 @@ public BooleanTypedValue getValueInternal(ExpressionState state) throws Evaluati
 			result = BooleanTypedValue.FALSE;  // null is not an instanceof anything
 		}
 		else {
-			result = BooleanTypedValue.forValue(rightClass.isAssignableFrom(leftValue.getClass()));
+			result = BooleanTypedValue.forValue(rightClass.isInstance(leftValue));
 		}
 		this.type = rightClass;
 		if (rightOperand instanceof TypeReference) {

spring-jdbc/src/main/java/org/springframework/jdbc/support/GeneratedKeyHolder.java

@@ -78,7 +78,7 @@ public GeneratedKeyHolder(List<Map<String, Object>> keyList) {
 		Iterator<Object> keyIter = this.keyList.get(0).values().iterator();
 		if (keyIter.hasNext()) {
 			Object key = keyIter.next();
-			if (key == null || !(keyType.isAssignableFrom(key.getClass()))) {
+			if (key == null || !(keyType.isInstance(key))) {
 				throw new DataRetrievalFailureException(
 						"The generated key type is not supported. " +
 						"Unable to cast [" + (key != null ? key.getClass().getName() : null) +

spring-jdbc/src/test/java/org/springframework/jdbc/support/CustomSQLExceptionTranslatorRegistrarTests.java

@@ -45,11 +45,11 @@ void customErrorCodeTranslation() {
 
 		DataAccessException exFor4200 = sext.doTranslate("", "", new SQLException("Ouch", "42000", 42000));
 		assertThat(exFor4200).as("Should have been translated").isNotNull();
-		assertThat(BadSqlGrammarException.class.isAssignableFrom(exFor4200.getClass())).as("Should have been instance of BadSqlGrammarException").isTrue();
+		assertThat(exFor4200).isInstanceOf(BadSqlGrammarException.class);
 
 		DataAccessException exFor2 = sext.doTranslate("", "", new SQLException("Ouch", "42000", 2));
 		assertThat(exFor2).as("Should have been translated").isNotNull();
-		assertThat(TransientDataAccessResourceException.class.isAssignableFrom(exFor2.getClass())).as("Should have been instance of TransientDataAccessResourceException").isTrue();
+		assertThat(exFor2).isInstanceOf(TransientDataAccessResourceException.class);
 
 		DataAccessException exFor3 = sext.doTranslate("", "", new SQLException("Ouch", "42000", 3));
 		assertThat(exFor3).as("Should not have been translated").isNull();

spring-messaging/src/main/java/org/springframework/messaging/MessageHeaders.java

@@ -205,7 +205,7 @@ protected static IdGenerator getIdGenerator() {
 		if (value == null) {
 			return null;
 		}
-		if (!type.isAssignableFrom(value.getClass())) {
+		if (!type.isInstance(value)) {
 			throw new IllegalArgumentException("Incorrect type specified for header '" +
 					key + "'. Expected [" + type + "] but actual type is [" + value.getClass() + "]");
 		}

spring-messaging/src/main/java/org/springframework/messaging/handler/CompositeMessageCondition.java

@@ -57,7 +57,7 @@ public List<MessageCondition<?>> getMessageConditions() {
 	@SuppressWarnings("unchecked")
 	public <T extends MessageCondition<T>> T getCondition(Class<T> messageConditionType) {
 		for (MessageCondition<?> condition : this.messageConditions) {
-			if (messageConditionType.isAssignableFrom(condition.getClass())) {
+			if (messageConditionType.isInstance(condition)) {
 				return (T) condition;
 			}
 		}