Fix setter detection in configprops endpoint

Previously, the setter of a property whose second letter is upper-case (
such as `oAuth2Uri`) was not detected properly. The JavaBean spec states
that, in such a case, the first letter should not be capitalized (i.e.
the setter should be `setoAuth2Uri` rather than `setOAuth2Uri`).

This commit makes sure that Jackson uses standard bean names and fixes
the setter detection algorithm to take this case into account.

Closes gh-13878

Author: snicoll

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/context/properties/ConfigurationPropertiesReportEndpoint.java

@@ -26,6 +26,7 @@
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.MapperFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationConfig;
 import com.fasterxml.jackson.databind.SerializationFeature;
@@ -172,6 +173,7 @@ private Map<String, Object> safeSerialize(ObjectMapper mapper, Object bean,
 	 */
 	protected void configureObjectMapper(ObjectMapper mapper) {
 		mapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
+		mapper.configure(MapperFeature.USE_STD_BEAN_NAMING, true);
 		mapper.setSerializationInclusion(Include.NON_NULL);
 		applyConfigurationPropertiesFilter(mapper);
 		applySerializationModifier(mapper);
@@ -375,7 +377,7 @@ private boolean isReadable(BeanDescription beanDesc, BeanPropertyWriter writer)
 
 		private AnnotatedMethod findSetter(BeanDescription beanDesc,
 				BeanPropertyWriter writer) {
-			String name = "set" + StringUtils.capitalize(writer.getName());
+			String name = "set" + determineAccessorSuffix(writer.getName());
 			Class<?> type = writer.getType().getRawClass();
 			AnnotatedMethod setter = beanDesc.findMethod(name, new Class<?>[] { type });
 			// The enabled property of endpoints returns a boolean primitive but is set
@@ -386,6 +388,23 @@ private AnnotatedMethod findSetter(BeanDescription beanDesc,
 			return setter;
 		}
 
+		/**
+		 * Determine the accessor suffix of the specified {@code propertyName}, see
+		 * section 8.8 "Capitalization of inferred names" of the JavaBean specs for more
+		 * details.
+		 * @param propertyName the property name to turn into an accessor suffix
+		 * @return the accessor suffix for {@code propertyName}
+		 */
+		private String determineAccessorSuffix(String propertyName) {
+			if (propertyName.length() > 1
+					&& Character.isUpperCase(propertyName.charAt(1))) {
+				return propertyName;
+			}
+			else {
+				return StringUtils.capitalize(propertyName);
+			}
+		}
+
 	}
 
 	/**

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/context/properties/ConfigurationPropertiesReportEndpointTests.java

@@ -44,6 +44,7 @@
  *
  * @author Dave Syer
  * @author Andy Wilkinson
+ * @author Stephane Nicoll
  */
 public class ConfigurationPropertiesReportEndpointTests {
 
@@ -120,6 +121,24 @@ public void keySanitizationWithCustomPatternUsingCompositeKeys() {
 				});
 	}
 
+	@Test
+	public void nonCamelCaseProperty() {
+		load((context, properties) -> {
+			Map<String, Object> nestedProperties = properties.getBeans()
+					.get("testProperties").getProperties();
+			assertThat(nestedProperties.get("myURL")).isEqualTo("https://example.com");
+		});
+	}
+
+	@Test
+	public void simpleBoolean() {
+		load((context, properties) -> {
+			Map<String, Object> nestedProperties = properties.getBeans()
+					.get("testProperties").getProperties();
+			assertThat(nestedProperties.get("simpleBoolean")).isEqualTo(true);
+		});
+	}
+
 	@Test
 	public void mixedBoolean() {
 		load((context, properties) -> {
@@ -129,6 +148,24 @@ public void mixedBoolean() {
 		});
 	}
 
+	@Test
+	public void mixedCase() {
+		load((context, properties) -> {
+			Map<String, Object> nestedProperties = properties.getBeans()
+					.get("testProperties").getProperties();
+			assertThat(nestedProperties.get("mIxedCase")).isEqualTo("mixed");
+		});
+	}
+
+	@Test
+	public void singleLetterProperty() {
+		load((context, properties) -> {
+			Map<String, Object> nestedProperties = properties.getBeans()
+					.get("testProperties").getProperties();
+			assertThat(nestedProperties.get("z")).isEqualTo("zzz");
+		});
+	}
+
 	@Test
 	@SuppressWarnings("unchecked")
 	public void listsAreSanitized() {
@@ -219,8 +256,16 @@ public static class TestProperties {
 
 		private String myTestProperty = "654321";
 
+		private String myURL = "https://example.com";
+
+		private boolean simpleBoolean = true;
+
 		private Boolean mixedBoolean = true;
 
+		private String mIxedCase = "mixed";
+
+		private String z = "zzz";
+
 		private Map<String, Object> secrets = new HashMap<>();
 
 		private Hidden hidden = new Hidden();
@@ -254,14 +299,46 @@ public void setMyTestProperty(String myTestProperty) {
 			this.myTestProperty = myTestProperty;
 		}
 
-		public boolean isMixedBoolean() {
-			return (this.mixedBoolean != null) ? this.mixedBoolean : false;
+		public String getMyURL() {
+			return this.myURL;
+		}
+
+		public void setMyURL(String myURL) {
+			this.myURL = myURL;
+		}
+
+		public boolean isSimpleBoolean() {
+			return this.simpleBoolean;
+		}
+
+		public void setSimpleBoolean(boolean simpleBoolean) {
+			this.simpleBoolean = simpleBoolean;
 		}
 
 		public void setMixedBoolean(Boolean mixedBoolean) {
 			this.mixedBoolean = mixedBoolean;
 		}
 
+		public boolean isMixedBoolean() {
+			return (this.mixedBoolean != null) ? this.mixedBoolean : false;
+		}
+
+		public String getmIxedCase() {
+			return this.mIxedCase;
+		}
+
+		public void setmIxedCase(String mIxedCase) {
+			this.mIxedCase = mIxedCase;
+		}
+
+		public String getZ() {
+			return this.z;
+		}
+
+		public void setZ(String z) {
+			this.z = z;
+		}
+
 		public Map<String, Object> getSecrets() {
 			return this.secrets;
 		}