GH-10083: Apply Nullability to syslog module

Related to: #10083

Signed-off-by: Tran Ngoc Nhan <ngocnhan.tran1996@gmail.com>

Author: ngocnhan-tran1996

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/DefaultMessageConverter.java

@@ -23,6 +23,8 @@
 import java.util.Map.Entry;
 import java.util.Set;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.integration.support.DefaultMessageBuilderFactory;
@@ -53,7 +55,7 @@ public class DefaultMessageConverter implements MessageConverter, BeanFactoryAwa
 
 	private volatile boolean asMap = true;
 
-	private BeanFactory beanFactory;
+	private @Nullable BeanFactory beanFactory;
 
 	/**
 	 * Set false will leave the payload as the original complete syslog.

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/RFC5424SyslogParser.java

@@ -21,6 +21,8 @@
 import java.util.List;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.integration.JavaUtils;
 import org.springframework.util.Assert;
 
@@ -131,7 +133,7 @@ public RFC5424SyslogParser(boolean retainOriginal) {
 	 * @param r the reader.
 	 * @return the timestamp.
 	 */
-	protected Object getTimestamp(Reader r) {
+	protected @Nullable Object getTimestamp(Reader r) {
 
 		int c = r.getc();
 
@@ -152,7 +154,7 @@ protected Object getTimestamp(Reader r) {
 		return dateBuilder.toString();
 	}
 
-	private Object getStructuredData(Reader r) {
+	private @Nullable Object getStructuredData(Reader r) {
 		if (r.is(NILVALUE)) {
 			r.getc();
 			return null;

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/config/SyslogReceivingChannelAdapterFactoryBean.java

@@ -16,6 +16,8 @@
 
 package org.springframework.integration.syslog.config;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanNameAware;
 import org.springframework.beans.factory.config.AbstractFactoryBean;
 import org.springframework.context.ApplicationEventPublisher;
@@ -47,31 +49,31 @@ public enum Protocol {
 		udp, tcp
 	}
 
-	private volatile SyslogReceivingChannelAdapterSupport syslogAdapter;
+	private volatile @Nullable SyslogReceivingChannelAdapterSupport syslogAdapter;
 
 	private final Protocol protocol;
 
-	private volatile MessageChannel outputChannel;
+	private volatile @Nullable MessageChannel outputChannel;
 
 	private volatile boolean autoStartup = true;
 
-	private volatile MessageChannel errorChannel;
+	private volatile @Nullable MessageChannel errorChannel;
 
 	private volatile int phase;
 
-	private volatile Long sendTimeout;
+	private volatile @Nullable Long sendTimeout;
 
-	private volatile AbstractServerConnectionFactory connectionFactory;
+	private volatile @Nullable AbstractServerConnectionFactory connectionFactory;
 
-	private volatile UnicastReceivingChannelAdapter udpAdapter;
+	private volatile @Nullable UnicastReceivingChannelAdapter udpAdapter;
 
-	private volatile Integer port;
+	private volatile @Nullable Integer port;
 
-	private volatile MessageConverter converter;
+	private volatile @Nullable MessageConverter converter;
 
-	private volatile String beanName;
+	private volatile @Nullable String beanName;
 
-	private volatile ApplicationEventPublisher applicationEventPublisher;
+	private volatile @Nullable ApplicationEventPublisher applicationEventPublisher;
 
 	/**
 	 * Instantiates a factory bean that creates a {@link UdpSyslogReceivingChannelAdapter}

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/config/package-info.java

@@ -1,4 +1,5 @@
 /**
  * Provides classes for configuration - parsers, namespace handlers, factory beans.
  */
+@org.jspecify.annotations.NullMarked
 package org.springframework.integration.syslog.config;

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/inbound/TcpSyslogReceivingChannelAdapter.java

@@ -36,8 +36,10 @@
 public class TcpSyslogReceivingChannelAdapter extends SyslogReceivingChannelAdapterSupport
 		implements TcpListener, ApplicationEventPublisherAware {
 
+	@SuppressWarnings("NullAway.Init")
 	private volatile AbstractServerConnectionFactory connectionFactory;
 
+	@SuppressWarnings("NullAway.Init")
 	private volatile ApplicationEventPublisher applicationEventPublisher;
 
 	/**

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/inbound/UdpSyslogReceivingChannelAdapter.java

@@ -30,6 +30,7 @@
  */
 public class UdpSyslogReceivingChannelAdapter extends SyslogReceivingChannelAdapterSupport {
 
+	@SuppressWarnings("NullAway.Init")
 	private volatile UnicastReceivingChannelAdapter udpAdapter;
 
 	private volatile boolean udpAdapterSet;

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/inbound/package-info.java

@@ -1,4 +1,5 @@
 /**
  * Provides classes for inbound endpoints.
  */
+@org.jspecify.annotations.NullMarked
 package org.springframework.integration.syslog.inbound;

spring-integration-syslog/src/main/java/org/springframework/integration/syslog/package-info.java

@@ -1,4 +1,5 @@
 /**
  * Base package for Syslog Support.
  */
+@org.jspecify.annotations.NullMarked
 package org.springframework.integration.syslog;