Added @Nonnull to parameters. Fixed some bugs in null checks.

wicket-auth-roles/pom.xml

@@ -35,6 +35,10 @@
 		<osgi.import.package>!java*,!kotlin*,!sun.nio.ch,org.slf4j*;version="[1.7,3)",*</osgi.import.package>
 	</properties>
 	<dependencies>
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.apache.wicket</groupId>
 			<artifactId>wicket-core</artifactId>

wicket-auth-roles/src/main/java/module-info.java

@@ -20,6 +20,7 @@
     requires org.apache.wicket.util;
     requires org.apache.wicket.request;
     requires org.apache.wicket.core;
+    requires jakarta.annotation;
 
     exports org.apache.wicket.authroles.authentication;
     exports org.apache.wicket.authroles.authentication.pages;

wicket-auth-roles/src/main/java/org/apache/wicket/authroles/authorization/strategies/role/AbstractRoleAuthorizationStrategy.java

@@ -16,6 +16,8 @@
  */
 package org.apache.wicket.authroles.authorization.strategies.role;
 
+import jakarta.annotation.Nonnull;
+
 import org.apache.wicket.authorization.IAuthorizationStrategy;
 import org.apache.wicket.util.lang.Args;
 
@@ -36,7 +38,7 @@ public abstract class AbstractRoleAuthorizationStrategy extends IAuthorizationSt
 	 * @param roleCheckingStrategy
 	 *            the authorizer delegate
 	 */
-	public AbstractRoleAuthorizationStrategy(IRoleCheckingStrategy roleCheckingStrategy)
+	public AbstractRoleAuthorizationStrategy(@Nonnull IRoleCheckingStrategy roleCheckingStrategy)
 	{
 		Args.notNull(roleCheckingStrategy, "roleCheckingStrategy");
 		this.roleCheckingStrategy = roleCheckingStrategy;

wicket-auth-roles/src/main/java/org/apache/wicket/authroles/authorization/strategies/role/Roles.java

@@ -19,6 +19,8 @@
 import java.util.Collection;
 import java.util.HashSet;
 
+import jakarta.annotation.Nonnull;
+
 import org.apache.wicket.util.io.IClusterable;
 import org.apache.wicket.util.lang.Args;
 import org.apache.wicket.util.string.StringList;
@@ -53,7 +55,7 @@ public Roles()
 	 * @param roles
 	 *            Roles as a comma separated list, like "ADMIN, USER"
 	 */
-	public Roles(final String roles)
+	public Roles(@Nonnull final String roles)
 	{
 		Args.notNull(roles, "roles");
 		for (final String role : roles.split("\\s*,\\s*"))
@@ -68,7 +70,7 @@ public Roles(final String roles)
 	 * @param roles
 	 *            Roles
 	 */
-	public Roles(final String[] roles)
+	public Roles(@Nonnull final String[] roles)
 	{
 		Args.notNull(roles, "roles");
 		for (final String role : roles)
@@ -77,7 +79,7 @@ public Roles(final String[] roles)
 		}
 	}
 
-	public Roles(final Collection<String> roles) {
+	public Roles(@Nonnull final Collection<String> roles) {
 		Args.notNull(roles, "roles");
 		addAll(roles);
 	}

wicket-bean-validation/pom.xml

@@ -42,6 +42,10 @@
 	</dependencyManagement>
 
 	<dependencies>
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>jakarta.el</groupId>
 			<artifactId>jakarta.el-api</artifactId>

wicket-bean-validation/src/main/java/module-info.java

@@ -19,6 +19,7 @@
     requires org.apache.wicket.util;
     requires org.apache.wicket.core;
     requires jakarta.validation;
+    requires jakarta.annotation;
 
     exports org.apache.wicket.bean.validation;
 }

wicket-bean-validation/src/main/java/org/apache/wicket/bean/validation/BeanValidationConfiguration.java

@@ -25,6 +25,7 @@
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.function.Supplier;
 
+import jakarta.annotation.Nonnull;
 import jakarta.validation.Validator;
 import jakarta.validation.constraints.NotEmpty;
 import jakarta.validation.constraints.NotNull;
@@ -99,8 +100,8 @@ public BeanValidationConfiguration()
 	 *            tag modifier to use
 	 * @return {@code this}
 	 */
-	public <T extends Annotation> BeanValidationConfiguration register(Class<T> annotationType,
-		ITagModifier<T> modifier)
+	public <T extends Annotation> BeanValidationConfiguration register(@Nonnull Class<T> annotationType,
+		@Nonnull ITagModifier<T> modifier)
 	{
 		Args.notNull(annotationType, "annotationType");
 		Args.notNull(modifier, "modifier");
@@ -117,7 +118,7 @@ public <T extends Annotation> BeanValidationConfiguration register(Class<T> anno
 	 */
 	@Override
 	@SuppressWarnings("unchecked")
-	public <T extends Annotation> ITagModifier<T> getTagModifier(Class<T> annotationType)
+	public <T extends Annotation> ITagModifier<T> getTagModifier(@Nonnull Class<T> annotationType)
 	{
 		Args.notNull(annotationType, "annotationType");
 
@@ -131,7 +132,7 @@ public <T extends Annotation> ITagModifier<T> getTagModifier(Class<T> annotation
 	 * @param resolver
 	 * @return {@code this}
 	 */
-	public BeanValidationConfiguration add(IPropertyResolver resolver)
+	public BeanValidationConfiguration add(@Nonnull IPropertyResolver resolver)
 	{
 		Args.notNull(resolver, "resolver");
 
@@ -156,7 +157,7 @@ public Validator getValidator()
 	 * 
 	 * @param validatorProvider
 	 */
-	public void setValidatorProvider(Supplier<Validator> validatorProvider)
+	public void setValidatorProvider(@Nonnull Supplier<Validator> validatorProvider)
 	{
 		Args.notNull(validatorProvider, "validatorProvider");
 
@@ -187,7 +188,7 @@ public IViolationTranslator getViolationTranslator()
 	 *            A violation translator that will convert {@link jakarta.validation.ConstraintViolation}s into Wicket's
 	 *            {@link org.apache.wicket.validation.ValidationError}s
 	 */
-	public void setViolationTranslator(IViolationTranslator violationTranslator)
+	public void setViolationTranslator(@Nonnull IViolationTranslator violationTranslator)
 	{
 		Args.notNull(violationTranslator, "violationTranslator");
 

wicket-bean-validation/src/main/java/org/apache/wicket/bean/validation/BeanValidationContext.java

@@ -18,6 +18,7 @@
 
 import java.lang.annotation.Annotation;
 
+import jakarta.annotation.Nonnull;
 import jakarta.validation.Validator;
 import jakarta.validation.metadata.ConstraintDescriptor;
 
@@ -41,7 +42,7 @@ public interface BeanValidationContext extends IPropertyResolver
 	 * @param annotationType
 	 * @return tag modifier or {@code null} if none
 	 */
-	<T extends Annotation> ITagModifier<T> getTagModifier(Class<T> annotationType);
+	<T extends Annotation> ITagModifier<T> getTagModifier(@Nonnull Class<T> annotationType);
 
 	/**
 	 * @return the validator

wicket-bean-validation/src/main/java/org/apache/wicket/bean/validation/Property.java

@@ -18,6 +18,8 @@
 
 import java.io.Serializable;
 
+import jakarta.annotation.Nonnull;
+
 import org.apache.wicket.util.lang.Args;
 import org.apache.wicket.util.reference.ClassReference;
 
@@ -31,7 +33,7 @@ public final class Property implements Serializable
 	private final ClassReference<?> owner;
 	private final String name;
 
-	public Property(ClassReference<?> owner, String name)
+	public Property(@Nonnull ClassReference<?> owner, @Nonnull String name)
 	{
 		Args.notNull(owner, "owner");
 		Args.notEmpty(name, "name");

wicket-bean-validation/src/main/java/org/apache/wicket/bean/validation/PropertyValidator.java

@@ -21,6 +21,7 @@
 import java.util.Iterator;
 import java.util.Set;
 
+import jakarta.annotation.Nonnull;
 import jakarta.validation.ConstraintViolation;
 import jakarta.validation.Validator;
 import jakarta.validation.groups.Default;
@@ -150,7 +151,7 @@ private Class<?>[] getGroups()
 
 	@SuppressWarnings("unchecked")
 	@Override
-	public void bind(Component component)
+	public void bind(@Nonnull Component component)
 	{
 		if (this.component != null)
 		{

wicket-bean-validation/src/main/java/org/apache/wicket/bean/validation/SessionLocaleInterpolator.java

@@ -18,6 +18,7 @@
 
 import java.util.Locale;
 
+import jakarta.annotation.Nonnull;
 import jakarta.validation.MessageInterpolator;
 
 import org.apache.wicket.Session;
@@ -38,7 +39,7 @@ public class SessionLocaleInterpolator implements MessageInterpolator
 	 * @param delegate
 	 *            the MessageInterpolator to delegate to
 	 */
-	public SessionLocaleInterpolator(MessageInterpolator delegate)
+	public SessionLocaleInterpolator(@Nonnull MessageInterpolator delegate)
 	{
 		Args.notNull(delegate, "delegate");
 		this.delegate = delegate;

wicket-cdi/src/main/java/org/apache/wicket/cdi/ConversationPropagator.java

@@ -16,6 +16,7 @@
  */
 package org.apache.wicket.cdi;
 
+import jakarta.annotation.Nonnull;
 import jakarta.enterprise.context.ContextNotActiveException;
 import jakarta.enterprise.context.Conversation;
 import jakarta.enterprise.context.ConversationScoped;
@@ -77,7 +78,7 @@ public class ConversationPropagator implements IRequestCycleListener
 	 * @param application
 	 * @param propagation
 	 */
-	public ConversationPropagator(Application application, IConversationPropagation propagation)
+	public ConversationPropagator(@Nonnull Application application, @Nonnull IConversationPropagation propagation)
 	{
 		Args.notNull(application, "application");
 		Args.notNull(propagation, "propagation");

wicket-core-tests/pom.xml

@@ -36,6 +36,11 @@
 		<japicmp.skip>true</japicmp.skip> <!-- this module is not released -->
 	</properties>
 	<dependencies>
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>jakarta.servlet</groupId>
 			<artifactId>jakarta.servlet-api</artifactId>

wicket-core-tests/src/test/java/org/apache/wicket/core/request/mapper/BasicResourceReferenceMapperTest.java

@@ -16,15 +16,13 @@
  */
 package org.apache.wicket.core.request.mapper;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNull;
-
 import java.io.Serializable;
 import java.util.Locale;
 import java.util.function.Supplier;
 import java.util.regex.Pattern;
 
+import jakarta.annotation.Nonnull;
+
 import org.apache.wicket.request.IRequestHandler;
 import org.apache.wicket.request.Url;
 import org.apache.wicket.request.handler.resource.ResourceReferenceRequestHandler;
@@ -47,6 +45,10 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
 /**
  * @author Matej Knopp
  */
@@ -584,7 +586,7 @@ private static class AlphaDigitResourceVersion implements IResourceVersion
 		 * @param version
 		 *             static version string to deliver for all queries resources
 		 */
-		AlphaDigitResourceVersion(String version)
+		AlphaDigitResourceVersion(@Nonnull String version)
 		{
 			this.version = Args.notNull(version, "version");
 		}

wicket-core-tests/src/test/java/org/apache/wicket/core/util/tester/WicketTesterTest.java

@@ -692,7 +692,7 @@ void executeAjaxEvent_ajaxFormSubmitLink()
 		// executeAjaxEvent weren't submitting the form the name would have been
 		// reset to null, because the form would have been updated but there
 		// wouldn't be any data to update it with.
-		assertNotNull("executeAjaxEvent() did not properly submit the form", pojo.getName());
+		assertNotNull(pojo.getName(), "executeAjaxEvent() did not properly submit the form");
 		assertEquals("Mock name", pojo.getName());
 	}
 

wicket-core/pom.xml

@@ -148,6 +148,10 @@ org.apache.wicket.validation.validator;-noimport:=true
 		<osgi.import.package>!java*,!kotlin*,!sun.nio.ch,!com.sun.crypto.provider,org.slf4j*;version="[1.7,3)",jakarta.servlet,jakarta.servlet.http,*</osgi.import.package>
 	</properties>
 	<dependencies>
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>com.github.openjson</groupId>
 			<artifactId>openjson</artifactId>

wicket-core/src/main/java/module-info.java

@@ -30,6 +30,7 @@
     requires org.danekja.jdk.serializable.functional;
     requires com.github.openjson;
     requires static org.bouncycastle.provider;
+    requires jakarta.annotation;
 
     provides org.apache.wicket.IInitializer with org.apache.wicket.Initializer;
     provides org.apache.wicket.resource.FileSystemPathService with org.apache.wicket.resource.FileSystemJarPathService;

wicket-core/src/main/java/org/apache/wicket/Application.java

@@ -25,6 +25,9 @@
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Supplier;
+
+import jakarta.annotation.Nonnull;
+
 import org.apache.wicket.application.ComponentInitializationListenerCollection;
 import org.apache.wicket.application.ComponentInstantiationListenerCollection;
 import org.apache.wicket.application.ComponentOnAfterRenderListenerCollection;
@@ -673,7 +676,7 @@ public Supplier<IExceptionMapper> getExceptionMapperProvider()
 		return exceptionMapperProvider;
 	}
 
-	public void setExceptionMapperProvider(Supplier<IExceptionMapper> exceptionMapperProvider) {
+	public void setExceptionMapperProvider(@Nonnull Supplier<IExceptionMapper> exceptionMapperProvider) {
 		this.exceptionMapperProvider = Args.notNull(exceptionMapperProvider, "exceptionMapperProvider");
 	}
 
@@ -690,7 +693,7 @@ public final Supplier<ISessionStore> getSessionStoreProvider()
 	 * 
 	 * @param sessionStoreProvider
 	 */
-	public final Application setSessionStoreProvider(final Supplier<ISessionStore> sessionStoreProvider)
+	public final Application setSessionStoreProvider(@Nonnull final Supplier<ISessionStore> sessionStoreProvider)
 	{
 		this.sessionStoreProvider = Args.notNull(sessionStoreProvider, "sessionStoreProvider");
 		this.sessionStore = null;
@@ -800,7 +803,7 @@ protected void validateInit()
 	 * @param name
 	 *            unique application name
 	 */
-	public final void setName(final String name)
+	public final void setName(@Nonnull final String name)
 	{
 		Args.notEmpty(name, "name");
 
@@ -1392,7 +1395,7 @@ public final IPageRendererProvider getPageRendererProvider()
 	 * 
 	 * @param pageRendererProvider
 	 */
-	public final Application setPageRendererProvider(final IPageRendererProvider pageRendererProvider)
+	public final Application setPageRendererProvider(@Nonnull final IPageRendererProvider pageRendererProvider)
 	{
 		Args.notNull(pageRendererProvider, "pageRendererProvider");
 		this.pageRendererProvider = pageRendererProvider;
@@ -1519,7 +1522,7 @@ protected IMapperContext newMapperContext()
 	 * @param requestCycle
 	 * @return Session
 	 */
-	public Session fetchCreateAndSetSession(final RequestCycle requestCycle)
+	public Session fetchCreateAndSetSession(@Nonnull final RequestCycle requestCycle)
 	{
 		Args.notNull(requestCycle, "requestCycle");