Add nullability annotations to module/spring-boot-jetty

See gh-46587

Author: mhalbritter

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/ConfigurableJettyWebServerFactory.java

@@ -18,6 +18,7 @@
 
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.util.thread.ThreadPool;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.web.server.ConfigurableWebServerFactory;
 
@@ -41,7 +42,7 @@ public interface ConfigurableJettyWebServerFactory extends ConfigurableWebServer
 	 * {@code null} (default), the {@link Server} creates a {@link ThreadPool} implicitly.
 	 * @param threadPool the ThreadPool to be used
 	 */
-	void setThreadPool(ThreadPool threadPool);
+	void setThreadPool(@Nullable ThreadPool threadPool);
 
 	/**
 	 * Set the number of selector threads to use.

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/GracefulShutdown.java

@@ -29,6 +29,7 @@
 
 import org.springframework.boot.web.server.GracefulShutdownCallback;
 import org.springframework.boot.web.server.GracefulShutdownResult;
+import org.springframework.util.Assert;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -70,10 +71,12 @@ private void shutdown(Connector connector, boolean getResult) {
 		}
 		catch (NoSuchMethodError ex) {
 			Method shutdown = ReflectionUtils.findMethod(connector.getClass(), "shutdown");
+			Assert.state(shutdown != null, "'shutdown' must not be null");
 			result = (Future<Void>) ReflectionUtils.invokeMethod(shutdown, connector);
 		}
 		if (getResult) {
 			try {
+				Assert.state(result != null, "'result' must not be null");
 				result.get();
 			}
 			catch (InterruptedException ex) {

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/JettyWebServer.java

@@ -32,6 +32,7 @@
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.server.handler.ContextHandler;
 import org.eclipse.jetty.server.handler.StatisticsHandler;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.jetty.reactive.JettyReactiveWebServerFactory;
 import org.springframework.boot.web.server.GracefulShutdownCallback;
@@ -65,7 +66,7 @@ public class JettyWebServer implements WebServer {
 
 	private final boolean autoStart;
 
-	private final GracefulShutdown gracefulShutdown;
+	private final @Nullable GracefulShutdown gracefulShutdown;
 
 	private Connector[] connectors;
 
@@ -92,19 +93,19 @@ public JettyWebServer(Server server, boolean autoStart) {
 		initialize();
 	}
 
-	private GracefulShutdown createGracefulShutdown(Server server) {
+	private @Nullable GracefulShutdown createGracefulShutdown(Server server) {
 		StatisticsHandler statisticsHandler = findStatisticsHandler(server);
 		if (statisticsHandler == null) {
 			return null;
 		}
 		return new GracefulShutdown(server, statisticsHandler::getRequestsActive);
 	}
 
-	private StatisticsHandler findStatisticsHandler(Server server) {
+	private @Nullable StatisticsHandler findStatisticsHandler(Server server) {
 		return findStatisticsHandler(server.getHandler());
 	}
 
-	private StatisticsHandler findStatisticsHandler(Handler handler) {
+	private @Nullable StatisticsHandler findStatisticsHandler(Handler handler) {
 		if (handler instanceof StatisticsHandler statisticsHandler) {
 			return statisticsHandler;
 		}
@@ -209,7 +210,7 @@ private String getProtocols(Connector connector) {
 		return " (" + StringUtils.collectionToDelimitedString(protocols, ", ") + ")";
 	}
 
-	private String getContextPath() {
+	private @Nullable String getContextPath() {
 		List<ContextHandler> imperativeContextHandlers = this.server.getHandlers()
 			.stream()
 			.map(this::findContextHandler)
@@ -222,7 +223,7 @@ private String getContextPath() {
 		return imperativeContextHandlers.stream().map(ContextHandler::getContextPath).collect(Collectors.joining(" "));
 	}
 
-	private ContextHandler findContextHandler(Handler handler) {
+	private @Nullable ContextHandler findContextHandler(Handler handler) {
 		while (handler instanceof Handler.Wrapper handlerWrapper) {
 			if (handler instanceof ContextHandler contextHandler) {
 				return contextHandler;

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/JettyWebServerFactory.java

@@ -38,8 +38,10 @@
 import org.eclipse.jetty.server.ServerConnector;
 import org.eclipse.jetty.util.thread.Scheduler;
 import org.eclipse.jetty.util.thread.ThreadPool;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.web.server.AbstractConfigurableWebServerFactory;
+import org.springframework.boot.web.server.Ssl;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -54,7 +56,7 @@ public class JettyWebServerFactory extends AbstractConfigurableWebServerFactory
 
 	private int acceptors = -1;
 
-	private ThreadPool threadPool;
+	private @Nullable ThreadPool threadPool;
 
 	private int selectors = -1;
 
@@ -160,12 +162,12 @@ public void addConfigurations(Configuration... configurations) {
 	 * Returns a Jetty {@link ThreadPool} that should be used by the {@link Server}.
 	 * @return a Jetty {@link ThreadPool} or {@code null}
 	 */
-	public ThreadPool getThreadPool() {
+	public @Nullable ThreadPool getThreadPool() {
 		return this.threadPool;
 	}
 
 	@Override
-	public void setThreadPool(ThreadPool threadPool) {
+	public void setThreadPool(@Nullable ThreadPool threadPool) {
 		this.threadPool = threadPool;
 	}
 
@@ -182,8 +184,8 @@ protected AbstractConnector createConnector(InetSocketAddress address, Server se
 		return this.createConnector(address, server, null, null, null);
 	}
 
-	protected AbstractConnector createConnector(InetSocketAddress address, Server server, Executor executor,
-			Scheduler scheduler, ByteBufferPool pool) {
+	protected AbstractConnector createConnector(InetSocketAddress address, Server server, @Nullable Executor executor,
+			@Nullable Scheduler scheduler, @Nullable ByteBufferPool pool) {
 		HttpConfiguration httpConfiguration = new HttpConfiguration();
 		httpConfiguration.setSendServerVersion(false);
 		List<ConnectionFactory> connectionFactories = new ArrayList<>();
@@ -200,8 +202,10 @@ protected AbstractConnector createConnector(InetSocketAddress address, Server se
 	}
 
 	protected void customizeSsl(Server server, InetSocketAddress address) {
-		Assert.state(getSsl().getServerNameBundles().isEmpty(), "Server name SSL bundles are not supported with Jetty");
-		new SslServerCustomizer(getHttp2(), address, getSsl().getClientAuth(), getSslBundle()).customize(server);
+		Ssl ssl = getSsl();
+		Assert.state(ssl != null, "'ssl' must not be null");
+		Assert.state(ssl.getServerNameBundles().isEmpty(), "Server name SSL bundles are not supported with Jetty");
+		new SslServerCustomizer(getHttp2(), address, ssl.getClientAuth(), getSslBundle()).customize(server);
 	}
 
 	protected Handler addHandlerWrappers(Handler handler) {

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/SslServerCustomizer.java

@@ -31,6 +31,7 @@
 import org.eclipse.jetty.server.ServerConnector;
 import org.eclipse.jetty.server.SslConnectionFactory;
 import org.eclipse.jetty.util.ssl.SslContextFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.ssl.SslBundle;
 import org.springframework.boot.ssl.SslBundleKey;
@@ -52,15 +53,16 @@
  */
 class SslServerCustomizer implements JettyServerCustomizer {
 
-	private final Http2 http2;
+	private final @Nullable Http2 http2;
 
 	private final InetSocketAddress address;
 
-	private final ClientAuth clientAuth;
+	private final @Nullable ClientAuth clientAuth;
 
 	private final SslBundle sslBundle;
 
-	SslServerCustomizer(Http2 http2, InetSocketAddress address, ClientAuth clientAuth, SslBundle sslBundle) {
+	SslServerCustomizer(@Nullable Http2 http2, InetSocketAddress address, @Nullable ClientAuth clientAuth,
+			SslBundle sslBundle) {
 		this.address = address;
 		this.clientAuth = clientAuth;
 		this.sslBundle = sslBundle;
@@ -156,7 +158,7 @@ private boolean isConscryptPresent() {
 	 * @param factory the Jetty {@link Server SslContextFactory.Server}.
 	 * @param clientAuth the client authentication mode
 	 */
-	protected void configureSsl(SslContextFactory.Server factory, ClientAuth clientAuth) {
+	protected void configureSsl(SslContextFactory.Server factory, @Nullable ClientAuth clientAuth) {
 		SslBundleKey key = this.sslBundle.getKey();
 		SslOptions options = this.sslBundle.getOptions();
 		SslStoreBundle stores = this.sslBundle.getStores();
@@ -186,7 +188,7 @@ protected void configureSsl(SslContextFactory.Server factory, ClientAuth clientA
 		}
 	}
 
-	private void configureSslClientAuth(SslContextFactory.Server factory, ClientAuth clientAuth) {
+	private void configureSslClientAuth(SslContextFactory.Server factory, @Nullable ClientAuth clientAuth) {
 		factory.setWantClientAuth(clientAuth == ClientAuth.WANT || clientAuth == ClientAuth.NEED);
 		factory.setNeedClientAuth(clientAuth == ClientAuth.NEED);
 	}

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/autoconfigure/JettyServerProperties.java

@@ -19,6 +19,8 @@
 import java.time.Duration;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.util.unit.DataSize;
 
@@ -66,7 +68,7 @@ public class JettyServerProperties {
 	/**
 	 * Time that the connection can be idle before it is closed.
 	 */
-	private Duration connectionIdleTimeout;
+	private @Nullable Duration connectionIdleTimeout;
 
 	/**
 	 * Maximum size of the HTTP response header.
@@ -113,11 +115,11 @@ public void setMaxFormKeys(int maxFormKeys) {
 		this.maxFormKeys = maxFormKeys;
 	}
 
-	public Duration getConnectionIdleTimeout() {
+	public @Nullable Duration getConnectionIdleTimeout() {
 		return this.connectionIdleTimeout;
 	}
 
-	public void setConnectionIdleTimeout(Duration connectionIdleTimeout) {
+	public void setConnectionIdleTimeout(@Nullable Duration connectionIdleTimeout) {
 		this.connectionIdleTimeout = connectionIdleTimeout;
 	}
 
@@ -156,17 +158,17 @@ public static class Accesslog {
 		 * Custom log format, see org.eclipse.jetty.server.CustomRequestLog. If defined,
 		 * overrides the "format" configuration key.
 		 */
-		private String customFormat;
+		private @Nullable String customFormat;
 
 		/**
 		 * Log filename. If not specified, logs redirect to "System.err".
 		 */
-		private String filename;
+		private @Nullable String filename;
 
 		/**
 		 * Date format to place in log file name.
 		 */
-		private String fileDateFormat;
+		private @Nullable String fileDateFormat;
 
 		/**
 		 * Number of days before rotated log files are deleted.
@@ -181,7 +183,7 @@ public static class Accesslog {
 		/**
 		 * Request paths that should not be logged.
 		 */
-		private List<String> ignorePaths;
+		private @Nullable List<String> ignorePaths;
 
 		public boolean isEnabled() {
 			return this.enabled;
@@ -199,27 +201,27 @@ public void setFormat(Accesslog.Format format) {
 			this.format = format;
 		}
 
-		public String getCustomFormat() {
+		public @Nullable String getCustomFormat() {
 			return this.customFormat;
 		}
 
-		public void setCustomFormat(String customFormat) {
+		public void setCustomFormat(@Nullable String customFormat) {
 			this.customFormat = customFormat;
 		}
 
-		public String getFilename() {
+		public @Nullable String getFilename() {
 			return this.filename;
 		}
 
-		public void setFilename(String filename) {
+		public void setFilename(@Nullable String filename) {
 			this.filename = filename;
 		}
 
-		public String getFileDateFormat() {
+		public @Nullable String getFileDateFormat() {
 			return this.fileDateFormat;
 		}
 
-		public void setFileDateFormat(String fileDateFormat) {
+		public void setFileDateFormat(@Nullable String fileDateFormat) {
 			this.fileDateFormat = fileDateFormat;
 		}
 
@@ -239,11 +241,11 @@ public void setAppend(boolean append) {
 			this.append = append;
 		}
 
-		public List<String> getIgnorePaths() {
+		public @Nullable List<String> getIgnorePaths() {
 			return this.ignorePaths;
 		}
 
-		public void setIgnorePaths(List<String> ignorePaths) {
+		public void setIgnorePaths(@Nullable List<String> ignorePaths) {
 			this.ignorePaths = ignorePaths;
 		}
 
@@ -299,7 +301,7 @@ public static class Threads {
 		 * Maximum capacity of the thread pool's backing queue. A default is computed
 		 * based on the threading configuration.
 		 */
-		private Integer maxQueueCapacity;
+		private @Nullable Integer maxQueueCapacity;
 
 		/**
 		 * Maximum thread idle time.
@@ -338,11 +340,11 @@ public Integer getMax() {
 			return this.max;
 		}
 
-		public Integer getMaxQueueCapacity() {
+		public @Nullable Integer getMaxQueueCapacity() {
 			return this.maxQueueCapacity;
 		}
 
-		public void setMaxQueueCapacity(Integer maxQueueCapacity) {
+		public void setMaxQueueCapacity(@Nullable Integer maxQueueCapacity) {
 			this.maxQueueCapacity = maxQueueCapacity;
 		}
 

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/autoconfigure/JettyThreadPool.java

@@ -22,6 +22,9 @@
 import org.eclipse.jetty.util.BlockingArrayQueue;
 import org.eclipse.jetty.util.thread.QueuedThreadPool;
 import org.eclipse.jetty.util.thread.ThreadPool;
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.lang.Contract;
 
 /**
  * Creates a {@link ThreadPool} for Jetty, applying
@@ -44,7 +47,8 @@ static QueuedThreadPool create(JettyServerProperties.Threads properties) {
 		return new QueuedThreadPool(maxThreadCount, minThreadCount, threadIdleTimeout, queue);
 	}
 
-	private static BlockingQueue<Runnable> determineBlockingQueue(Integer maxQueueCapacity) {
+	@Contract("!null -> !null")
+	private static @Nullable BlockingQueue<Runnable> determineBlockingQueue(@Nullable Integer maxQueueCapacity) {
 		if (maxQueueCapacity == null) {
 			return null;
 		}

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/autoconfigure/actuate/web/server/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Auto-configuration for Jetty actuator web concerns.
  */
+@NullMarked
 package org.springframework.boot.jetty.autoconfigure.actuate.web.server;
+
+import org.jspecify.annotations.NullMarked;

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/autoconfigure/metrics/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Auto-configuration for Jetty metrics.
  */
+@NullMarked
 package org.springframework.boot.jetty.autoconfigure.metrics;
+
+import org.jspecify.annotations.NullMarked;

module/spring-boot-jetty/src/main/java/org/springframework/boot/jetty/autoconfigure/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Auto-configuration for Jetty.
  */
+@NullMarked
 package org.springframework.boot.jetty.autoconfigure;
+
+import org.jspecify.annotations.NullMarked;