Nullability fine-tuning around declaration inconsistencies

Issue: SPR-15720
Issue: SPR-15792

spring-tx/src/main/java/org/springframework/jca/cci/connection/ConnectionSpecConnectionFactoryAdapter.java

@@ -68,6 +68,7 @@ import org.springframework.util.Assert;
 @SuppressWarnings("serial")
 public class ConnectionSpecConnectionFactoryAdapter extends DelegatingConnectionFactory {
 
+	@Nullable
 	private ConnectionSpec connectionSpec;
 
 	private final ThreadLocal<ConnectionSpec> threadBoundSpec =

spring-tx/src/main/java/org/springframework/jca/cci/core/support/CommAreaRecord.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -35,11 +35,11 @@ import org.springframework.util.FileCopyUtils;
 @SuppressWarnings("serial")
 public class CommAreaRecord implements Record, Streamable {
 
-	private byte[] bytes;
+	private byte[] bytes = new byte[0];
 
-	private String recordName;
+	private String recordName = "";
 
-	private String recordShortDescription;
+	private String recordShortDescription = "";
 
 
 	/**
@@ -60,22 +60,22 @@ public class CommAreaRecord implements Record, Streamable {
 
 	@Override
 	public void setRecordName(String recordName) {
-		this.recordName=recordName;
+		this.recordName = recordName;
 	}
 
 	@Override
 	public String getRecordName() {
-		return recordName;
+		return this.recordName;
 	}
 
 	@Override
 	public void setRecordShortDescription(String recordShortDescription) {
-		this.recordShortDescription=recordShortDescription;
+		this.recordShortDescription = recordShortDescription;
 	}
 
 	@Override
 	public String getRecordShortDescription() {
-		return recordShortDescription;
+		return this.recordShortDescription;
 	}
 
 

spring-tx/src/main/java/org/springframework/jca/context/SpringContextResourceAdapter.java

@@ -122,6 +122,7 @@ public class SpringContextResourceAdapter implements ResourceAdapter {
 
 	private String contextConfigLocation = DEFAULT_CONTEXT_CONFIG_LOCATION;
 
+	@Nullable
 	private ConfigurableApplicationContext applicationContext;
 
 
@@ -208,7 +209,9 @@ public class SpringContextResourceAdapter implements ResourceAdapter {
 	@Override
 	public void stop() {
 		logger.info("Stopping SpringContextResourceAdapter");
-		this.applicationContext.close();
+		if (this.applicationContext != null) {
+			this.applicationContext.close();
+		}
 	}
 
 

spring-tx/src/main/java/org/springframework/jca/endpoint/GenericMessageEndpointFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -26,6 +26,8 @@ import org.aopalliance.intercept.MethodInvocation;
 
 import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.aop.support.DelegatingIntroductionInterceptor;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -52,6 +54,7 @@ import org.springframework.util.ReflectionUtils;
  */
 public class GenericMessageEndpointFactory extends AbstractMessageEndpointFactory {
 
+	@Nullable
 	private Object messageListener;
 
 
@@ -64,6 +67,15 @@ public class GenericMessageEndpointFactory extends AbstractMessageEndpointFactor
 		this.messageListener = messageListener;
 	}
 
+	/**
+	 * Return the message listener object for this endpoint.
+	 * @since 5.0
+	 */
+	protected Object getMessageListener() {
+		Assert.state(this.messageListener != null, "No message listener set");
+		return this.messageListener;
+	}
+
 	/**
 	 * Wrap each concrete endpoint instance with an AOP proxy,
 	 * exposing the message listener's interfaces as well as the
@@ -72,7 +84,7 @@ public class GenericMessageEndpointFactory extends AbstractMessageEndpointFactor
 	@Override
 	public MessageEndpoint createEndpoint(XAResource xaResource) throws UnavailableException {
 		GenericMessageEndpoint endpoint = (GenericMessageEndpoint) super.createEndpoint(xaResource);
-		ProxyFactory proxyFactory = new ProxyFactory(this.messageListener);
+		ProxyFactory proxyFactory = new ProxyFactory(getMessageListener());
 		DelegatingIntroductionInterceptor introduction = new DelegatingIntroductionInterceptor(endpoint);
 		introduction.suppressInterface(MethodInterceptor.class);
 		proxyFactory.addAdvice(introduction);
@@ -136,7 +148,7 @@ public class GenericMessageEndpointFactory extends AbstractMessageEndpointFactor
 
 		@Override
 		protected ClassLoader getEndpointClassLoader() {
-			return messageListener.getClass().getClassLoader();
+			return getMessageListener().getClass().getClassLoader();
 		}
 	}
 

spring-tx/src/main/java/org/springframework/transaction/interceptor/BeanFactoryTransactionAttributeSourceAdvisor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -19,6 +19,7 @@ package org.springframework.transaction.interceptor;
 import org.springframework.aop.ClassFilter;
 import org.springframework.aop.Pointcut;
 import org.springframework.aop.support.AbstractBeanFactoryPointcutAdvisor;
+import org.springframework.lang.Nullable;
 
 /**
  * Advisor driven by a {@link TransactionAttributeSource}, used to include
@@ -33,6 +34,7 @@ import org.springframework.aop.support.AbstractBeanFactoryPointcutAdvisor;
 @SuppressWarnings("serial")
 public class BeanFactoryTransactionAttributeSourceAdvisor extends AbstractBeanFactoryPointcutAdvisor {
 
+	@Nullable
 	private TransactionAttributeSource transactionAttributeSource;
 
 	private final TransactionAttributeSourcePointcut pointcut = new TransactionAttributeSourcePointcut() {

spring-tx/src/main/java/org/springframework/transaction/interceptor/DefaultTransactionAttribute.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -91,6 +91,7 @@ public class DefaultTransactionAttribute extends DefaultTransactionDefinition im
 	 * @since 3.0
 	 */
 	@Override
+	@Nullable
 	public String getQualifier() {
 		return this.qualifier;
 	}

spring-tx/src/main/java/org/springframework/transaction/support/DefaultTransactionDefinition.java

@@ -216,6 +216,7 @@ public class DefaultTransactionDefinition implements TransactionDefinition, Seri
 	}
 
 	@Override
+	@Nullable
 	public final String getName() {
 		return this.name;
 	}