Fix Spring plugin: In lower versions of Spring, adding new interfaces results in parameter validation errors for requests.

plugin/hotswap-agent-spring-plugin/src/main/java/org/hotswap/agent/plugin/spring/SpringPlugin.java

@@ -51,15 +51,7 @@
 import org.hotswap.agent.plugin.spring.reload.XmlsChangedCommand;
 import org.hotswap.agent.plugin.spring.reload.YamlChangedCommand;
 import org.hotswap.agent.plugin.spring.scanner.SpringBeanWatchEventListener;
-import org.hotswap.agent.plugin.spring.transformers.BeanFactoryTransformer;
-import org.hotswap.agent.plugin.spring.transformers.ClassPathBeanDefinitionScannerTransformer;
-import org.hotswap.agent.plugin.spring.transformers.ConfigurationClassPostProcessorTransformer;
-import org.hotswap.agent.plugin.spring.transformers.InitDestroyAnnotationBeanPostProcessorTransformer;
-import org.hotswap.agent.plugin.spring.transformers.PlaceholderConfigurerSupportTransformer;
-import org.hotswap.agent.plugin.spring.transformers.PostProcessorRegistrationDelegateTransformer;
-import org.hotswap.agent.plugin.spring.transformers.ProxyReplacerTransformer;
-import org.hotswap.agent.plugin.spring.transformers.ResourcePropertySourceTransformer;
-import org.hotswap.agent.plugin.spring.transformers.XmlBeanDefinitionScannerTransformer;
+import org.hotswap.agent.plugin.spring.transformers.*;
 import org.hotswap.agent.util.HotswapTransformer;
 import org.hotswap.agent.util.IOUtils;
 import org.hotswap.agent.util.PluginManagerInvoker;
@@ -81,7 +73,8 @@
                 XmlBeanDefinitionScannerTransformer.class,
                 PostProcessorRegistrationDelegateTransformer.class,
                 BeanFactoryTransformer.class,
-                InitDestroyAnnotationBeanPostProcessorTransformer.class})
+                InitDestroyAnnotationBeanPostProcessorTransformer.class,
+                SpringMvcTransformer.class})
 @Versions(manifest = {@Manifest(value = "[3.1.0,)", versionName= Name.ImplementationVersion, names={
         @Name(key=Name.ImplementationTitle,value="spring-core")})})
 public class SpringPlugin {

plugin/hotswap-agent-spring-plugin/src/main/java/org/hotswap/agent/plugin/spring/core/ResetRequestParameterCaches.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2013-2024 the HotswapAgent authors.
+ *
+ * This file is part of HotswapAgent.
+ *
+ * HotswapAgent is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * HotswapAgent is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with HotswapAgent. If not, see http://www.gnu.org/licenses/.
+ */
+package org.hotswap.agent.plugin.spring.core;
+
+import org.hotswap.agent.logging.AgentLogger;
+import org.hotswap.agent.util.ReflectionHelper;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Support for Spring MVC Parameter caches.
+ */
+public class ResetRequestParameterCaches {
+
+    private static AgentLogger LOGGER = AgentLogger.getLogger(ResetRequestParameterCaches.class);
+
+    private static Set<Object> localParameterNameDiscovers = new HashSet<>();
+
+    private static Class<?> getLocalVariableTableParameterNameDiscovererClassOrNull() {
+        try {
+            //This is probably a bad idea as Class.forName has lots of issues but this was easiest for now.
+            return Class.forName("org.springframework.core.LocalVariableTableParameterNameDiscoverer");
+        } catch (ClassNotFoundException e) {
+            LOGGER.trace("LocalVariableTableParameterNameDiscoverer class not found");
+            return null;
+        }
+    }
+
+    public static void setLocalParameterNameDiscovers(Object localVariableNameDiscoverer) {
+        localParameterNameDiscovers.add(localVariableNameDiscoverer);
+    }
+
+    public static void reset(DefaultListableBeanFactory beanFactory, Set<Class<?>> clazzes) {
+
+        Class<?> c = getLocalVariableTableParameterNameDiscovererClassOrNull();
+        if (c == null) {
+            return;
+        }
+
+        try {
+            for (Object localParameterNameDiscover : localParameterNameDiscovers) {
+                Object parameterNamesCacheObj = ReflectionHelper.getNoException(localParameterNameDiscover, c, "parameterNamesCache");
+                if (parameterNamesCacheObj == null) {
+                    return;
+                }
+                if (!(parameterNamesCacheObj instanceof Map)) {
+                    return;
+                }
+
+                Map<Object, Object> parameterNamesCache = (Map<Object, Object>) parameterNamesCacheObj;
+                for (Class clazz : clazzes) {
+                    parameterNamesCache.remove(clazz);
+                }
+            }
+        } catch (Exception e) {
+            LOGGER.error("Failed to clear parameterNamesCache", e);
+        }
+    }
+
+}

plugin/hotswap-agent-spring-plugin/src/main/java/org/hotswap/agent/plugin/spring/reload/SpringBeanReload.java

@@ -527,6 +527,7 @@ private void clearSpringCache() {
 //        ResetBeanFactoryCaches.reset(beanFactory);
         ConfigurationClassPostProcessorEnhance.getInstance(beanFactory).resetConfigurationClassPostProcessor(beanFactory);
         ResetAnnotationCache.resetAnnotationScanner(beanFactory);
+        ResetRequestParameterCaches.reset(beanFactory, classes);
     }
 
     private void clearLocalCache() {

plugin/hotswap-agent-spring-plugin/src/main/java/org/hotswap/agent/plugin/spring/transformers/SpringMvcTransformer.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2013-2024 the HotswapAgent authors.
+ *
+ * This file is part of HotswapAgent.
+ *
+ * HotswapAgent is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * HotswapAgent is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with HotswapAgent. If not, see http://www.gnu.org/licenses/.
+ */
+package org.hotswap.agent.plugin.spring.transformers;
+
+import org.hotswap.agent.annotation.OnClassLoadEvent;
+import org.hotswap.agent.javassist.*;
+import org.hotswap.agent.logging.AgentLogger;
+
+public class SpringMvcTransformer {
+
+    private static final AgentLogger LOGGER = AgentLogger.getLogger(SpringMvcTransformer.class);
+
+    @OnClassLoadEvent(classNameRegexp = "org.springframework.core.LocalVariableTableParameterNameDiscoverer")
+    public static void replaceLocalVariableTableParameterNameDiscoverer(CtClass ctClass) throws NotFoundException, CannotCompileException {
+        CtConstructor[] constructors = ctClass.getConstructors();
+        for (CtConstructor ctConstructor : constructors) {
+            ctConstructor.insertAfter(" {org.hotswap.agent.plugin.spring.core.ResetRequestMappingCaches.setLocalParameterNameDiscovers(this);} ");
+        }
+
+        LOGGER.debug("LocalVariableTableParameterNameDiscoverer patched");
+    }
+}