Consistent nullability for internal field access

Author: jhoeller

spring-web/src/main/java/org/springframework/web/context/request/async/WebAsyncManager.java

@@ -142,8 +142,8 @@ public void setTaskExecutor(AsyncTaskExecutor taskExecutor) {
 	}
 
 	/**
-	 * Whether the selected handler for the current request chose to handle the
-	 * request asynchronously. A return value of "true" indicates concurrent
+	 * Return whether the selected handler for the current request chose to handle
+	 * the request asynchronously. A return value of "true" indicates concurrent
 	 * handling is under way and the response will remain open. A return value
 	 * of "false" means concurrent handling was either not started or possibly
 	 * that it has completed and the request was dispatched for further
@@ -154,16 +154,16 @@ public boolean isConcurrentHandlingStarted() {
 	}
 
 	/**
-	 * Whether a result value exists as a result of concurrent handling.
+	 * Return whether a result value exists as a result of concurrent handling.
 	 */
 	public boolean hasConcurrentResult() {
 		return (this.concurrentResult != RESULT_NONE);
 	}
 
 	/**
-	 * Provides access to the result from concurrent handling.
+	 * Get the result from concurrent handling.
 	 * @return an Object, possibly an {@code Exception} or {@code Throwable} if
-	 * concurrent handling raised one.
+	 * concurrent handling raised one
 	 * @see #clearConcurrentResult()
 	 */
 	@Nullable
@@ -172,8 +172,7 @@ public Object getConcurrentResult() {
 	}
 
 	/**
-	 * Provides access to additional processing context saved at the start of
-	 * concurrent handling.
+	 * Get the additional processing context saved at the start of concurrent handling.
 	 * @see #clearConcurrentResult()
 	 */
 	@Nullable
@@ -214,7 +213,7 @@ public void registerCallableInterceptor(Object key, CallableProcessingIntercepto
 
 	/**
 	 * Register a {@link CallableProcessingInterceptor} without a key.
-	 * The key is derived from the class name and hashcode.
+	 * The key is derived from the class name and hash code.
 	 * @param interceptors one or more interceptors to register
 	 */
 	public void registerCallableInterceptors(CallableProcessingInterceptor... interceptors) {
@@ -237,8 +236,8 @@ public void registerDeferredResultInterceptor(Object key, DeferredResultProcessi
 	}
 
 	/**
-	 * Register one or more {@link DeferredResultProcessingInterceptor DeferredResultProcessingInterceptors} without a specified key.
-	 * The default key is derived from the interceptor class name and hash code.
+	 * Register one or more {@link DeferredResultProcessingInterceptor DeferredResultProcessingInterceptors}
+	 * without a specified key. The default key is derived from the interceptor class name and hash code.
 	 * @param interceptors one or more interceptors to register
 	 */
 	public void registerDeferredResultInterceptors(DeferredResultProcessingInterceptor... interceptors) {
@@ -314,7 +313,7 @@ public void startCallableProcessing(final WebAsyncTask<?> webAsyncTask, Object..
 
 		this.asyncWebRequest.addTimeoutHandler(() -> {
 			if (logger.isDebugEnabled()) {
-				logger.debug("Async request timeout for " + formatRequestUri());
+				logger.debug("Async request timeout for " + formatUri(this.asyncWebRequest));
 			}
 			Object result = interceptorChain.triggerAfterTimeout(this.asyncWebRequest, callable);
 			if (result != CallableProcessingInterceptor.RESULT_NONE) {
@@ -325,7 +324,7 @@ public void startCallableProcessing(final WebAsyncTask<?> webAsyncTask, Object..
 		this.asyncWebRequest.addErrorHandler(ex -> {
 			if (!this.errorHandlingInProgress) {
 				if (logger.isDebugEnabled()) {
-					logger.debug("Async request error for " + formatRequestUri() + ": " + ex);
+					logger.debug("Async request error for " + formatUri(this.asyncWebRequest) + ": " + ex);
 				}
 				Object result = interceptorChain.triggerAfterError(this.asyncWebRequest, callable, ex);
 				result = (result != CallableProcessingInterceptor.RESULT_NONE ? result : ex);
@@ -361,11 +360,6 @@ public void startCallableProcessing(final WebAsyncTask<?> webAsyncTask, Object..
 		}
 	}
 
-	private String formatRequestUri() {
-		HttpServletRequest request = this.asyncWebRequest.getNativeRequest(HttpServletRequest.class);
-		return request != null ? request.getRequestURI() : "servlet container";
-	}
-
 	private void setConcurrentResultAndDispatch(@Nullable Object result) {
 		synchronized (WebAsyncManager.this) {
 			if (this.concurrentResult != RESULT_NONE) {
@@ -375,9 +369,10 @@ private void setConcurrentResultAndDispatch(@Nullable Object result) {
 			this.errorHandlingInProgress = (result instanceof Throwable);
 		}
 
+		Assert.state(this.asyncWebRequest != null, "AsyncWebRequest must not be null");
 		if (this.asyncWebRequest.isAsyncComplete()) {
 			if (logger.isDebugEnabled()) {
-				logger.debug("Async result set but request already complete: " + formatRequestUri());
+				logger.debug("Async result set but request already complete: " + formatUri(this.asyncWebRequest));
 			}
 			return;
 		}
@@ -388,7 +383,7 @@ private void setConcurrentResultAndDispatch(@Nullable Object result) {
 
 		if (logger.isDebugEnabled()) {
 			logger.debug("Async " + (this.errorHandlingInProgress ? "error" : "result set") +
-					", dispatch to " + formatRequestUri());
+					", dispatch to " + formatUri(this.asyncWebRequest));
 		}
 		this.asyncWebRequest.dispatch();
 	}
@@ -472,11 +467,17 @@ private void startAsyncProcessing(Object[] processingContext) {
 			this.concurrentResultContext = processingContext;
 			this.errorHandlingInProgress = false;
 		}
-		this.asyncWebRequest.startAsync();
 
+		Assert.state(this.asyncWebRequest != null, "AsyncWebRequest must not be null");
+		this.asyncWebRequest.startAsync();
 		if (logger.isDebugEnabled()) {
 			logger.debug("Started async request");
 		}
 	}
 
+	private static String formatUri(AsyncWebRequest asyncWebRequest) {
+		HttpServletRequest request = asyncWebRequest.getNativeRequest(HttpServletRequest.class);
+		return (request != null ? request.getRequestURI() : "servlet container");
+	}
+
 }

spring-web/src/main/java/org/springframework/web/context/request/async/WebAsyncTask.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -47,12 +47,16 @@ public class WebAsyncTask<V> implements BeanFactoryAware {
 	@Nullable
 	private final String executorName;
 
+	@Nullable
 	private BeanFactory beanFactory;
 
+	@Nullable
 	private Callable<V> timeoutCallback;
 
+	@Nullable
 	private Callable<V> errorCallback;
 
+	@Nullable
 	private Runnable completionCallback;