diff --git a/core/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/CollectionBinderTests.java b/core/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/CollectionBinderTests.java
index 3b8d79c44063..0638d6f00350 100644
--- a/core/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/CollectionBinderTests.java
+++ b/core/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/CollectionBinderTests.java
@@ -119,10 +119,10 @@ void bindToCollectionWhenNonSequentialShouldThrowException() {
 			.satisfies((ex) -> {
 				Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex.getCause())
 					.getUnboundProperties();
-				assertThat(unbound).hasSize(1);
-				ConfigurationProperty property = unbound.iterator().next();
-				assertThat(property.getName()).hasToString("foo[3]");
-				assertThat(property.getValue()).isEqualTo("3");
+				assertThat(unbound).singleElement().satisfies((property) -> {
+					assertThat(property.getName()).hasToString("foo[3]");
+					assertThat(property.getValue()).isEqualTo("3");
+				});
 			});
 	}
 
@@ -139,10 +139,10 @@ void bindToCollectionWhenNonKnownIndexedChildNotBoundThrowsException() {
 			.satisfies((ex) -> {
 				Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex.getCause())
 					.getUnboundProperties();
-				assertThat(unbound).hasSize(1);
-				ConfigurationProperty property = unbound.iterator().next();
-				assertThat(property.getName()).hasToString("foo[1].missing");
-				assertThat(property.getValue()).isEqualTo("bad");
+				assertThat(unbound).singleElement().satisfies((property) -> {
+					assertThat(property.getName()).hasToString("foo[1].missing");
+					assertThat(property.getValue()).isEqualTo("bad");
+				});
 			});
 	}
 
@@ -155,10 +155,10 @@ void bindToNestedCollectionWhenNonKnownIndexed() {
 		source.put("foo[0].string", "test");
 		this.sources.add(source);
 		List<ExampleCollectionBean> list = this.binder.bind("foo", Bindable.listOf(ExampleCollectionBean.class)).get();
-		assertThat(list).hasSize(1);
-		ExampleCollectionBean bean = list.get(0);
-		assertThat(bean.getItems()).containsExactly("a", "b", "d");
-		assertThat(bean.getString()).isEqualTo("test");
+		assertThat(list).singleElement().satisfies((bean) -> {
+			assertThat(bean.getItems()).containsExactly("a", "b", "d");
+			assertThat(bean.getString()).isEqualTo("test");
+		});
 	}
 
 	@Test
@@ -173,10 +173,10 @@ void bindToNonScalarCollectionWhenNonSequentialShouldThrowException() {
 			.satisfies((ex) -> {
 				Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex.getCause())
 					.getUnboundProperties();
-				assertThat(unbound).hasSize(1);
-				ConfigurationProperty property = unbound.iterator().next();
-				assertThat(property.getName()).hasToString("foo[4].value");
-				assertThat(property.getValue()).isEqualTo("4");
+				assertThat(unbound).singleElement().satisfies((property) -> {
+					assertThat(property.getName()).hasToString("foo[4].value");
+					assertThat(property.getValue()).isEqualTo("4");
+				});
 			});
 	}
 
diff --git a/module/spring-boot-amqp/src/main/java/org/springframework/boot/amqp/autoconfigure/RabbitTemplateConfigurer.java b/module/spring-boot-amqp/src/main/java/org/springframework/boot/amqp/autoconfigure/RabbitTemplateConfigurer.java
index 2273e1d85859..a8af90eba1a0 100644
--- a/module/spring-boot-amqp/src/main/java/org/springframework/boot/amqp/autoconfigure/RabbitTemplateConfigurer.java
+++ b/module/spring-boot-amqp/src/main/java/org/springframework/boot/amqp/autoconfigure/RabbitTemplateConfigurer.java
@@ -33,7 +33,7 @@
  * properties.
  * <p>
  * Can be injected into application code and used to define a custom
- * {@code RabbitTemplateConfigurer} whose configuration is based upon that produced by
+ * {@code RabbitTemplate} whose configuration is based upon that produced by
  * auto-configuration.
  *
  * @author Stephane Nicoll
diff --git a/module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersProperties.java b/module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersProperties.java
index fb141e1fec32..47ffe28c21ff 100644
--- a/module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersProperties.java
+++ b/module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersProperties.java
@@ -31,7 +31,7 @@
 public class HttpMessageConvertersProperties {
 
 	/**
-	 * The charset to use for String conversion.
+	 * Charset to use for String conversion.
 	 */
 	private Charset stringEncodingCharset = StandardCharsets.UTF_8;
 
diff --git a/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroup.java b/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroup.java
index fb318c0ca449..85a86639d14b 100644
--- a/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroup.java
+++ b/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroup.java
@@ -65,7 +65,7 @@ default int compareTo(ObservationHandlerGroup other) {
 	Class<?> handlerType();
 
 	/**
-	 * Static factory method to create a {@link ObservationHandlerGroup} with members of
+	 * Static factory method to create an {@link ObservationHandlerGroup} with members of
 	 * the given handler type.
 	 * @param <H> the handler type
 	 * @param handlerType the handler type
diff --git a/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroups.java b/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroups.java
index 688dc705e889..5bf93b999d5a 100644
--- a/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroups.java
+++ b/module/spring-boot-observation/src/main/java/org/springframework/boot/observation/autoconfigure/ObservationHandlerGroups.java
@@ -29,7 +29,7 @@
 import org.springframework.util.MultiValueMap;
 
 /**
- * A collection {@link ObservationHandlerGroup} instance and supporting registration
+ * A collection of {@link ObservationHandlerGroup} instances and supporting registration
  * logic.
  *
  * @author Andy Wilkinson
diff --git a/module/spring-boot-tracing/src/main/java/org/springframework/boot/tracing/autoconfigure/TracingAndMeterObservationHandlerGroup.java b/module/spring-boot-tracing/src/main/java/org/springframework/boot/tracing/autoconfigure/TracingAndMeterObservationHandlerGroup.java
index f475f66ed202..57276a6b9edc 100644
--- a/module/spring-boot-tracing/src/main/java/org/springframework/boot/tracing/autoconfigure/TracingAndMeterObservationHandlerGroup.java
+++ b/module/spring-boot-tracing/src/main/java/org/springframework/boot/tracing/autoconfigure/TracingAndMeterObservationHandlerGroup.java
@@ -32,7 +32,7 @@
 /**
  * {@link ObservationHandlerGroup} that considers both {@link TracingObservationHandler}
  * and {@link MeterObservationHandler} types as members. This group takes precedence over
- * any regular {@link MeterObservationHandler} group in order to use ensure
+ * any regular {@link MeterObservationHandler} group in order to ensure
  * {@link TracingAwareMeterObservationHandler} wrapping is applied during registration.
  *
  * @author Phillip Webb