Replace redundant call to class isInstance() with instanceof

See gh-15554

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/server/OnManagementPortCondition.java

@@ -68,7 +68,7 @@ class OnManagementPortCondition extends SpringBootCondition {
 				context.getClassLoader())) {
 			return false;
 		}
-		return WebApplicationContext.class.isInstance(resourceLoader);
+		return resourceLoader instanceof WebApplicationContext;
 	}
 
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/ConditionMessage.java

@@ -61,7 +61,7 @@ public final class ConditionMessage {
 
 	@Override
 	public boolean equals(Object obj) {
-		if (obj == null || !ConditionMessage.class.isInstance(obj)) {
+		if (!(obj instanceof ConditionMessage)) {
 			return false;
 		}
 		if (obj == this) {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/hateoas/HypermediaAutoConfigurationTests.java

@@ -70,7 +70,7 @@ public class HypermediaAutoConfigurationTests {
 		LinkDiscoverers discoverers = this.context.getBean(LinkDiscoverers.class);
 		assertThat(discoverers).isNotNull();
 		LinkDiscoverer discoverer = discoverers.getLinkDiscovererFor(MediaTypes.HAL_JSON);
-		assertThat(HalLinkDiscoverer.class.isInstance(discoverer)).isTrue();
+		assertThat(discoverer instanceof HalLinkDiscoverer).isTrue();
 	}
 
 	@Test

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/LogbackLoggingSystem.java

@@ -198,7 +198,7 @@ public class LogbackLoggingSystem extends Slf4JLoggingSystem {
 		}
 		java.util.logging.Logger rootLogger = LogManager.getLogManager().getLogger("");
 		Handler[] handlers = rootLogger.getHandlers();
-		return handlers.length == 1 && SLF4JBridgeHandler.class.isInstance(handlers[0]);
+		return handlers.length == 1 && handlers[0] instanceof SLF4JBridgeHandler;
 	}
 
 	private void addLevelChangePropagator(LoggerContext loggerContext) {