Fix handling of primitive boolean @RequestParam with required=false

Signed-off-by: Aman Gautam <amangautam2128@gmail.com>

Author: Gautam-aman

spring-web/src/main/java/org/springframework/web/method/annotation/AbstractNamedValueMethodArgumentResolver.java

@@ -115,6 +115,8 @@ public AbstractNamedValueMethodArgumentResolver(@Nullable ConfigurableBeanFactor
 		}
 
 		Object arg = resolveName(resolvedName.toString(), nestedParameter, webRequest);
+		boolean valueMissing =
+				(resolveName(resolvedName.toString(), nestedParameter, webRequest) == null);
 		if (arg == null) {
 			if (namedValueInfo.defaultValue != null) {
 				arg = resolveEmbeddedValuesAndExpressions(namedValueInfo.defaultValue);
@@ -130,20 +132,32 @@ else if ("".equals(arg) && namedValueInfo.defaultValue != null) {
 			arg = resolveEmbeddedValuesAndExpressions(namedValueInfo.defaultValue);
 		}
 
-		if (binderFactory != null && (arg != null || !hasDefaultValue)) {
+
+		boolean skipConversion =
+				valueMissing &&
+						parameter.getParameterType().isPrimitive() &&
+						!namedValueInfo.required &&
+						!hasDefaultValue;
+
+
+
+		if (binderFactory != null && !skipConversion && (arg != null || !hasDefaultValue)) {
 			arg = convertIfNecessary(parameter, webRequest, binderFactory, namedValueInfo, arg);
-			// Check for null value after conversion of incoming argument value
 			if (arg == null) {
 				if (namedValueInfo.defaultValue != null) {
 					arg = resolveEmbeddedValuesAndExpressions(namedValueInfo.defaultValue);
-					arg = convertIfNecessary(parameter, webRequest, binderFactory, namedValueInfo, arg);
 				}
 				else if (namedValueInfo.required && !nestedParameter.isOptional()) {
-					handleMissingValueAfterConversion(resolvedName.toString(), nestedParameter, webRequest);
+					handleMissingValue(resolvedName.toString(), nestedParameter, webRequest);
+				}
+				else if (parameter.getParameterType().isPrimitive()) {
+					arg = handleNullValue(resolvedName.toString(), null, parameter.getParameterType());
 				}
 			}
+
 		}
 
+
 		handleResolvedValue(arg, namedValueInfo.name, parameter, mavContainer, webRequest);
 
 		return arg;

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/RequestMappingHandlerAdapterTests.java

@@ -256,6 +256,23 @@ void modelAttributeAdvice() throws Exception {
 		assertThat(mav.getModel().get("attr2")).isEqualTo("gAttr2");
 	}
 
+	@Test
+	void primitiveBooleanRequiredFalseShouldNotThrowTypeMismatch() throws Exception {
+		this.handlerAdapter.afterPropertiesSet();
+
+		this.request.setRequestURI("/test");
+
+		HandlerMethod handlerMethod =
+				handlerMethod(new PrimitiveBooleanController(), "test", boolean.class);
+
+		this.handlerAdapter.handle(this.request, this.response, handlerMethod);
+
+		assertThat(this.response.getContentAsString()).isEqualTo("false");
+	}
+
+
+
+
 	@Test
 	void prototypeControllerAdvice() throws Exception {
 		this.webAppContext.registerPrototype("maa", ModelAttributeAdvice.class);
@@ -440,6 +457,17 @@ void test(@RequestParam boolean bool) {
 		}
 	}
 
+	@RestController
+	static class PrimitiveBooleanController {
+
+		@GetMapping("/test")
+		public String test(@RequestParam(required = false) boolean flag) {
+			return String.valueOf(flag);
+		}
+	}
+
+
+
 
 
 	@ControllerAdvice