Deprecate LocalVariableTableParameterNameDiscoverer completely

LocalVariableTableParameterNameDiscoverer is not registered by default anymore now.
Java sources should be compiled with `-parameters` instead (available since Java 8).
Also retaining standard Java parameter names for all of Spring's Kotlin sources now.

Closes gh-29531

Author: jhoeller

buildSrc/src/main/java/org/springframework/build/KotlinConventions.java

@@ -38,6 +38,7 @@ private void configure(KotlinCompile compile) {
 		kotlinOptions.setApiVersion("1.7");
 		kotlinOptions.setLanguageVersion("1.7");
 		kotlinOptions.setJvmTarget("17");
+		kotlinOptions.setJavaParameters(true);
 		kotlinOptions.setAllWarningsAsErrors(true);
 		List<String> freeCompilerArgs = new ArrayList<>(compile.getKotlinOptions().getFreeCompilerArgs());
 		freeCompilerArgs.addAll(List.of("-Xsuppress-version-warnings", "-Xjsr305=strict", "-opt-in=kotlin.RequiresOptIn"));

framework-docs/src/docs/asciidoc/web/webflux.adoc

@@ -1532,8 +1532,8 @@ register support for any other data type.
 See <<webflux-ann-typeconversion>> and <<webflux-ann-initbinder>>.
 
 URI variables can be named explicitly (for example, `@PathVariable("customId")`), but you can
-leave that detail out if the names are the same and you compile your code with debugging
-information or with the `-parameters` compiler flag on Java 8.
+leave that detail out if the names are the same and you compile your code with the `-parameters`
+compiler flag.
 
 The syntax `{*varName}` declares a URI variable that matches zero or more remaining path
 segments. For example `/resources/{*path}` matches all files under `/resources/`, and the

framework-docs/src/docs/asciidoc/web/webmvc.adoc

@@ -1699,8 +1699,8 @@ register support for any other data type.
 See <<mvc-ann-typeconversion>> and <<mvc-ann-initbinder>>.
 
 You can explicitly name URI variables (for example, `@PathVariable("customId")`), but you can
-leave that detail out if the names are the same and your code is compiled with debugging
-information or with the `-parameters` compiler flag on Java 8.
+leave that detail out if the names are the same and your code is compiled with the `-parameters`
+compiler flag.
 
 The syntax `{varName:regex}` declares a URI variable with a regular expression that has
 syntax of `{varName:regex}`. For example, given URL `"/spring-web-3.0.5.jar"`, the following method

spring-beans/src/test/java/org/springframework/beans/factory/support/QualifierAnnotationAutowireBeanFactoryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,7 +27,7 @@
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.beans.factory.config.ConstructorArgumentValues;
 import org.springframework.beans.factory.config.DependencyDescriptor;
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.MethodParameter;
 import org.springframework.util.ClassUtils;
 
@@ -148,7 +148,7 @@ public void testAutowireCandidateWithConstructorDescriptor() throws Exception {
 		lbf.registerBeanDefinition(MARK, person2);
 		MethodParameter param = new MethodParameter(QualifiedTestBean.class.getDeclaredConstructor(Person.class), 0);
 		DependencyDescriptor qualifiedDescriptor = new DependencyDescriptor(param, false);
-		param.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		param.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		assertThat(param.getParameterName()).isEqualTo("tpb");
 		assertThat(lbf.isAutowireCandidate(JUERGEN, null)).isTrue();
 		assertThat(lbf.isAutowireCandidate(JUERGEN, qualifiedDescriptor)).isTrue();
@@ -174,9 +174,9 @@ public void testAutowireCandidateWithMethodDescriptor() throws Exception {
 				new MethodParameter(QualifiedTestBean.class.getDeclaredMethod("autowireNonqualified", Person.class), 0);
 		DependencyDescriptor qualifiedDescriptor = new DependencyDescriptor(qualifiedParam, false);
 		DependencyDescriptor nonqualifiedDescriptor = new DependencyDescriptor(nonqualifiedParam, false);
-		qualifiedParam.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		qualifiedParam.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		assertThat(qualifiedParam.getParameterName()).isEqualTo("tpb");
-		nonqualifiedParam.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		nonqualifiedParam.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		assertThat(nonqualifiedParam.getParameterName()).isEqualTo("tpb");
 		assertThat(lbf.isAutowireCandidate(JUERGEN, null)).isTrue();
 		assertThat(lbf.isAutowireCandidate(JUERGEN, nonqualifiedDescriptor)).isTrue();

spring-core/src/main/java/org/springframework/core/DefaultParameterNameDiscoverer.java

@@ -18,9 +18,7 @@
 
 /**
  * Default implementation of the {@link ParameterNameDiscoverer} strategy interface,
- * using the Java 8 standard reflection mechanism (if available), and falling back
- * to the ASM-based {@link LocalVariableTableParameterNameDiscoverer} (when not in
- * a native image) for checking debug information in the class file.
+ * delegating to the Java 8 standard reflection mechanism.
  *
  * <p>If a Kotlin reflection implementation is present,
  * {@link KotlinReflectionParameterNameDiscoverer} is added first in the list and
@@ -33,7 +31,6 @@
  * @author Sam Brannen
  * @since 4.0
  * @see StandardReflectionParameterNameDiscoverer
- * @see LocalVariableTableParameterNameDiscoverer
  * @see KotlinReflectionParameterNameDiscoverer
  */
 public class DefaultParameterNameDiscoverer extends PrioritizedParameterNameDiscoverer {
@@ -43,9 +40,6 @@ public DefaultParameterNameDiscoverer() {
 			addDiscoverer(new KotlinReflectionParameterNameDiscoverer());
 		}
 		addDiscoverer(new StandardReflectionParameterNameDiscoverer());
-		if (!NativeDetector.inNativeImage()) {
-			addDiscoverer(new LocalVariableTableParameterNameDiscoverer());
-		}
 	}
 
 }

spring-core/src/main/java/org/springframework/core/LocalVariableTableParameterNameDiscoverer.java

@@ -53,7 +53,9 @@
  * @author Chris Beams
  * @author Sam Brannen
  * @since 2.0
+ * @deprecated as of 6.0.1, in favor of {@link StandardReflectionParameterNameDiscoverer}
  */
+@Deprecated
 public class LocalVariableTableParameterNameDiscoverer implements ParameterNameDiscoverer {
 
 	private static final Log logger = LogFactory.getLog(LocalVariableTableParameterNameDiscoverer.class);

spring-messaging/src/test/java/org/springframework/messaging/handler/annotation/support/PayloadMethodArgumentResolverTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,7 +26,7 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.annotation.SynthesizingMethodParameter;
 import org.springframework.messaging.Message;
@@ -81,7 +81,7 @@ public void setup() throws Exception {
 		this.paramAnnotatedRequired = new SynthesizingMethodParameter(payloadMethod, 2);
 		this.paramWithSpelExpression = new SynthesizingMethodParameter(payloadMethod, 3);
 		this.paramValidated = new SynthesizingMethodParameter(payloadMethod, 4);
-		this.paramValidated.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		this.paramValidated.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		this.paramValidatedNotAnnotated = new SynthesizingMethodParameter(payloadMethod, 5);
 		this.paramNotAnnotated = new SynthesizingMethodParameter(payloadMethod, 6);
 	}

spring-messaging/src/test/java/org/springframework/messaging/handler/invocation/ResolvableMethod.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -39,7 +39,7 @@
 import org.springframework.cglib.proxy.Enhancer;
 import org.springframework.cglib.proxy.Factory;
 import org.springframework.cglib.proxy.MethodProxy;
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.MethodIntrospector;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.ParameterNameDiscoverer;
@@ -131,7 +131,7 @@ public class ResolvableMethod {
 
 	private static final SpringObjenesis objenesis = new SpringObjenesis();
 
-	private static final ParameterNameDiscoverer nameDiscoverer = new LocalVariableTableParameterNameDiscoverer();
+	private static final ParameterNameDiscoverer nameDiscoverer = new DefaultParameterNameDiscoverer();
 
 	// Matches ValueConstants.DEFAULT_NONE (spring-web and spring-messaging)
 	private static final String DEFAULT_VALUE_NONE = "\n\t\t\n\t\t\n\uE000\uE001\uE002\n\t\t\t\t\n";

spring-web/src/test/java/org/springframework/web/method/annotation/InitBinderDataBinderFactoryTests.java

@@ -21,7 +21,7 @@
 
 import org.junit.jupiter.api.Test;
 
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.format.support.DefaultFormattingConversionService;
 import org.springframework.web.bind.WebDataBinder;
@@ -128,7 +128,7 @@ private WebDataBinderFactory createFactory(String methodName, Class<?>... parame
 		InvocableHandlerMethod handlerMethod = new InvocableHandlerMethod(handler, method);
 		handlerMethod.setHandlerMethodArgumentResolvers(this.argumentResolvers);
 		handlerMethod.setDataBinderFactory(new DefaultDataBinderFactory(null));
-		handlerMethod.setParameterNameDiscoverer(new LocalVariableTableParameterNameDiscoverer());
+		handlerMethod.setParameterNameDiscoverer(new DefaultParameterNameDiscoverer());
 
 		return new InitBinderDataBinderFactory(
 				Collections.singletonList(handlerMethod), this.bindingInitializer);

spring-web/src/test/java/org/springframework/web/method/annotation/ModelFactoryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,7 +22,7 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.ui.Model;
 import org.springframework.ui.ModelMap;
 import org.springframework.validation.BindingResult;
@@ -252,7 +252,7 @@ private ModelFactory createModelFactory(String methodName, Class<?>... parameter
 		InvocableHandlerMethod modelMethod = createHandlerMethod(methodName, parameterTypes);
 		modelMethod.setHandlerMethodArgumentResolvers(resolvers);
 		modelMethod.setDataBinderFactory(null);
-		modelMethod.setParameterNameDiscoverer(new LocalVariableTableParameterNameDiscoverer());
+		modelMethod.setParameterNameDiscoverer(new DefaultParameterNameDiscoverer());
 
 		return new ModelFactory(Collections.singletonList(modelMethod), null, this.attributeHandler);
 	}

spring-web/src/testFixtures/java/org/springframework/web/testfixture/method/ResolvableMethod.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -39,7 +39,7 @@
 import org.springframework.cglib.proxy.Enhancer;
 import org.springframework.cglib.proxy.Factory;
 import org.springframework.cglib.proxy.MethodProxy;
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.MethodIntrospector;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.ParameterNameDiscoverer;
@@ -130,7 +130,7 @@ public class ResolvableMethod {
 
 	private static final SpringObjenesis objenesis = new SpringObjenesis();
 
-	private static final ParameterNameDiscoverer nameDiscoverer = new LocalVariableTableParameterNameDiscoverer();
+	private static final ParameterNameDiscoverer nameDiscoverer = new DefaultParameterNameDiscoverer();
 
 	// Matches ValueConstants.DEFAULT_NONE (spring-web and spring-messaging)
 	private static final String DEFAULT_VALUE_NONE = "\n\t\t\n\t\t\n\uE000\uE001\uE002\n\t\t\t\t\n";

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/InitBinderBindingContextTests.java

@@ -23,7 +23,7 @@
 
 import org.junit.jupiter.api.Test;
 
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.ReactiveAdapterRegistry;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.format.support.DefaultFormattingConversionService;
@@ -131,7 +131,7 @@ private BindingContext createBindingContext(String methodName, Class<?>... param
 
 		SyncInvocableHandlerMethod handlerMethod = new SyncInvocableHandlerMethod(handler, method);
 		handlerMethod.setArgumentResolvers(new ArrayList<>(this.argumentResolvers));
-		handlerMethod.setParameterNameDiscoverer(new LocalVariableTableParameterNameDiscoverer());
+		handlerMethod.setParameterNameDiscoverer(new DefaultParameterNameDiscoverer());
 
 		return new InitBinderBindingContext(this.bindingInitializer, Collections.singletonList(handlerMethod));
 	}

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

@@ -32,7 +32,7 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
+import org.springframework.core.DefaultParameterNameDiscoverer;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.annotation.SynthesizingMethodParameter;
 import org.springframework.http.HttpInputMessage;
@@ -137,28 +137,28 @@ public InputStream getInputStream() throws IOException {
 
 		Method method = ReflectionUtils.findMethod(getClass(), "handle", (Class<?>[]) null);
 		paramRequestPart = new SynthesizingMethodParameter(method, 0);
-		paramRequestPart.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		paramRequestPart.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		paramNamedRequestPart = new SynthesizingMethodParameter(method, 1);
 		paramValidRequestPart = new SynthesizingMethodParameter(method, 2);
 		paramMultipartFile = new SynthesizingMethodParameter(method, 3);
 		paramMultipartFileList = new SynthesizingMethodParameter(method, 4);
 		paramMultipartFileArray = new SynthesizingMethodParameter(method, 5);
 		paramInt = new SynthesizingMethodParameter(method, 6);
 		paramMultipartFileNotAnnot = new SynthesizingMethodParameter(method, 7);
-		paramMultipartFileNotAnnot.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		paramMultipartFileNotAnnot.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		paramPart = new SynthesizingMethodParameter(method, 8);
-		paramPart.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		paramPart.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		paramPartList = new SynthesizingMethodParameter(method, 9);
 		paramPartArray = new SynthesizingMethodParameter(method, 10);
 		paramRequestParamAnnot = new SynthesizingMethodParameter(method, 11);
 		optionalMultipartFile = new SynthesizingMethodParameter(method, 12);
-		optionalMultipartFile.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		optionalMultipartFile.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		optionalMultipartFileList = new SynthesizingMethodParameter(method, 13);
-		optionalMultipartFileList.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		optionalMultipartFileList.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		optionalPart = new SynthesizingMethodParameter(method, 14);
-		optionalPart.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		optionalPart.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		optionalPartList = new SynthesizingMethodParameter(method, 15);
-		optionalPartList.initParameterNameDiscovery(new LocalVariableTableParameterNameDiscoverer());
+		optionalPartList.initParameterNameDiscovery(new DefaultParameterNameDiscoverer());
 		optionalRequestPart = new SynthesizingMethodParameter(method, 16);
 	}