Add missing Nullable info in GraphiQL handlers

Fixes gh-1276

Author: bclozel

spring-graphql/src/main/java/org/springframework/graphql/server/webflux/GraphiQlHandler.java

@@ -18,11 +18,13 @@
 
 import java.net.URI;
 
+import org.jspecify.annotations.Nullable;
 import reactor.core.publisher.Mono;
 
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.Resource;
 import org.springframework.http.MediaType;
+import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 import org.springframework.web.reactive.function.server.ServerRequest;
 import org.springframework.web.reactive.function.server.ServerResponse;
@@ -39,7 +41,7 @@ public class GraphiQlHandler {
 
 	private final String graphQlPath;
 
-	private final String graphQlWsPath;
+	private final @Nullable String graphQlWsPath;
 
 	private final Resource htmlResource;
 
@@ -50,7 +52,7 @@ public class GraphiQlHandler {
 	 * @param graphQlPath the path to the GraphQL endpoint
 	 * @param graphQlWsPath optional path to the GraphQL WebSocket endpoint
 	 */
-	public GraphiQlHandler(String graphQlPath, String graphQlWsPath) {
+	public GraphiQlHandler(String graphQlPath, @Nullable String graphQlWsPath) {
 		this(graphQlPath, graphQlWsPath, new ClassPathResource("graphiql/index.html"));
 	}
 
@@ -60,7 +62,9 @@ public GraphiQlHandler(String graphQlPath, String graphQlWsPath) {
 	 * @param graphQlWsPath optional path to the GraphQL WebSocket endpoint
 	 * @param htmlResource the GraphiQL page to serve
 	 */
-	public GraphiQlHandler(String graphQlPath, String graphQlWsPath, Resource htmlResource) {
+	public GraphiQlHandler(String graphQlPath, @Nullable String graphQlWsPath, Resource htmlResource) {
+		Assert.hasText(graphQlPath, "graphQlPath should not be empty");
+		Assert.notNull(htmlResource, "HtmlResource is required");
 		this.graphQlPath = graphQlPath;
 		this.graphQlWsPath = graphQlWsPath;
 		this.htmlResource = htmlResource;

spring-graphql/src/main/java/org/springframework/graphql/server/webmvc/GraphiQlHandler.java

@@ -18,6 +18,8 @@
 
 import java.net.URI;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.Resource;
 import org.springframework.http.MediaType;
@@ -38,7 +40,7 @@ public class GraphiQlHandler {
 
 	private final String graphQlPath;
 
-	private final String graphQlWsPath;
+	private final @Nullable String graphQlWsPath;
 
 	private final Resource htmlResource;
 
@@ -49,7 +51,7 @@ public class GraphiQlHandler {
 	 * @param graphQlPath the path to the GraphQL HTTP endpoint
 	 * @param graphQlWsPath optional path to the GraphQL WebSocket endpoint
 	 */
-	public GraphiQlHandler(String graphQlPath, String graphQlWsPath) {
+	public GraphiQlHandler(String graphQlPath, @Nullable String graphQlWsPath) {
 		this(graphQlPath, graphQlWsPath, new ClassPathResource("graphiql/index.html"));
 	}
 
@@ -59,8 +61,9 @@ public GraphiQlHandler(String graphQlPath, String graphQlWsPath) {
 	 * @param graphQlWsPath optional path to the GraphQL WebSocket endpoint
 	 * @param htmlResource the GraphiQL page to serve
 	 */
-	public GraphiQlHandler(String graphQlPath, String graphQlWsPath, Resource htmlResource) {
+	public GraphiQlHandler(String graphQlPath, @Nullable String graphQlWsPath, Resource htmlResource) {
 		Assert.hasText(graphQlPath, "graphQlPath should not be empty");
+		Assert.notNull(htmlResource, "HtmlResource is required");
 		this.graphQlPath = graphQlPath;
 		this.graphQlWsPath = graphQlWsPath;
 		this.htmlResource = htmlResource;