Merge branch '5.3.x'

# Conflicts:
#	spring-context/src/main/java/org/springframework/context/annotation/CommonAnnotationBeanPostProcessor.java

spring-context/src/main/java/org/springframework/context/annotation/CommonAnnotationBeanPostProcessor.java

@@ -130,6 +130,10 @@ import org.springframework.util.StringValueResolver;
 public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBeanPostProcessor
 		implements InstantiationAwareBeanPostProcessor, BeanFactoryAware, Serializable {
 
+	// Defensive reference to JNDI API for JDK 9+ (optional java.naming module)
+	private static final boolean jndiPresent = ClassUtils.isPresent(
+			"javax.naming.InitialContext", CommonAnnotationBeanPostProcessor.class.getClassLoader());
+
 	private static final Set<Class<? extends Annotation>> resourceAnnotationTypes = new LinkedHashSet<>(4);
 
 	@Nullable
@@ -151,7 +155,8 @@ public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBean
 
 	private boolean alwaysUseJndiLookup = false;
 
-	private transient BeanFactory jndiFactory = new SimpleJndiBeanFactory();
+	@Nullable
+	private transient BeanFactory jndiFactory;
 
 	@Nullable
 	private transient BeanFactory resourceFactory;
@@ -175,6 +180,11 @@ public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBean
 		setOrder(Ordered.LOWEST_PRECEDENCE - 3);
 		setInitAnnotationType(PostConstruct.class);
 		setDestroyAnnotationType(PreDestroy.class);
+
+		// java.naming module present on JDK 9+?
+		if (jndiPresent) {
+			this.jndiFactory = new SimpleJndiBeanFactory();
+		}
 	}
 
 
@@ -421,6 +431,7 @@ public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBean
 			public void releaseTarget(Object target) {
 			}
 		};
+
 		ProxyFactory pf = new ProxyFactory();
 		pf.setTargetSource(ts);
 		if (element.lookupType.isInterface()) {
@@ -441,12 +452,23 @@ public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBean
 	protected Object getResource(LookupElement element, @Nullable String requestingBeanName)
 			throws NoSuchBeanDefinitionException {
 
+		// JNDI lookup to perform?
+		String jndiName = null;
 		if (StringUtils.hasLength(element.mappedName)) {
-			return this.jndiFactory.getBean(element.mappedName, element.lookupType);
+			jndiName = element.mappedName;
+		}
+		else if (this.alwaysUseJndiLookup) {
+			jndiName = element.name;
 		}
-		if (this.alwaysUseJndiLookup) {
-			return this.jndiFactory.getBean(element.name, element.lookupType);
+		if (jndiName != null) {
+			if (this.jndiFactory == null) {
+				throw new NoSuchBeanDefinitionException(element.lookupType,
+						"No JNDI factory configured - specify the 'jndiFactory' property");
+			}
+			return this.jndiFactory.getBean(jndiName, element.lookupType);
 		}
+
+		// Regular resource autowiring
 		if (this.resourceFactory == null) {
 			throw new NoSuchBeanDefinitionException(element.lookupType,
 					"No resource factory configured - specify the 'resourceFactory' property");

spring-core/src/main/java/org/springframework/core/env/AbstractEnvironment.java

@@ -47,6 +47,7 @@ import org.springframework.util.StringUtils;
  *
  * @author Chris Beams
  * @author Juergen Hoeller
+ * @author Phillip Webb
  * @since 3.1
  * @see ConfigurableEnvironment
  * @see StandardEnvironment
@@ -127,6 +128,7 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
 	 * {@link #customizePropertySources(MutablePropertySources)} during
 	 * construction to allow subclasses to contribute or manipulate
 	 * {@link PropertySource} instances as appropriate.
+	 * @param propertySources property sources to use
 	 * @since 5.3.4
 	 * @see #customizePropertySources(MutablePropertySources)
 	 */
@@ -136,6 +138,7 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
 		customizePropertySources(propertySources);
 	}
 
+
 	/**
 	 * Factory method used to create the {@link ConfigurablePropertyResolver}
 	 * instance used by the Environment.

spring-core/src/main/java/org/springframework/core/env/StandardEnvironment.java

@@ -46,6 +46,7 @@ package org.springframework.core.env;
  * variable names.
  *
  * @author Chris Beams
+ * @author Phillip Webb
  * @since 3.1
  * @see ConfigurableEnvironment
  * @see SystemEnvironmentPropertySource
@@ -61,13 +62,15 @@ public class StandardEnvironment extends AbstractEnvironment {
 
 
 	/**
-	 * Create a new {@code StandardEnvironment} instance.
+	 * Create a new {@code StandardEnvironment} instance with a default
+	 * {@link MutablePropertySources} instance.
 	 */
 	public StandardEnvironment() {
 	}
 
 	/**
-	 * Create a new {@code StandardEnvironment} instance with a specific {@link MutablePropertySources} instance.
+	 * Create a new {@code StandardEnvironment} instance with a specific
+	 * {@link MutablePropertySources} instance.
 	 * @param propertySources property sources to use
 	 * @since 5.3.4
 	 */

spring-jcl/src/main/java/org/apache/commons/logging/LogAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -278,7 +278,7 @@ final class LogAdapter {
 
 		protected final String name;
 
-		protected transient T logger;
+		protected final transient T logger;
 
 		public Slf4jLog(T logger) {
 			this.name = logger.getName();
@@ -500,9 +500,9 @@ final class LogAdapter {
 	@SuppressWarnings("serial")
 	private static class JavaUtilLog implements Log, Serializable {
 
-		private String name;
+		private final String name;
 
-		private transient java.util.logging.Logger logger;
+		private final transient java.util.logging.Logger logger;
 
 		public JavaUtilLog(String name) {
 			this.name = name;

spring-web/src/main/java/org/springframework/web/context/support/StandardServletEnvironment.java

@@ -27,6 +27,7 @@ import org.springframework.core.env.StandardEnvironment;
 import org.springframework.jndi.JndiLocatorDelegate;
 import org.springframework.jndi.JndiPropertySource;
 import org.springframework.lang.Nullable;
+import org.springframework.util.ClassUtils;
 import org.springframework.web.context.ConfigurableWebEnvironment;
 
 /**
@@ -39,6 +40,7 @@ import org.springframework.web.context.ConfigurableWebEnvironment;
  * documentation for details.
  *
  * @author Chris Beams
+ * @author Juergen Hoeller
  * @since 3.1
  * @see StandardEnvironment
  */
@@ -54,6 +56,11 @@ public class StandardServletEnvironment extends StandardEnvironment implements C
 	public static final String JNDI_PROPERTY_SOURCE_NAME = "jndiProperties";
 
 
+	// Defensive reference to JNDI API for JDK 9+ (optional java.naming module)
+	private static final boolean jndiPresent = ClassUtils.isPresent(
+			"javax.naming.InitialContext", StandardServletEnvironment.class.getClassLoader());
+
+
 	/**
 	 * Create a new {@code StandardServletEnvironment} instance.
 	 */
@@ -100,7 +107,7 @@ public class StandardServletEnvironment extends StandardEnvironment implements C
 	protected void customizePropertySources(MutablePropertySources propertySources) {
 		propertySources.addLast(new StubPropertySource(SERVLET_CONFIG_PROPERTY_SOURCE_NAME));
 		propertySources.addLast(new StubPropertySource(SERVLET_CONTEXT_PROPERTY_SOURCE_NAME));
-		if (JndiLocatorDelegate.isDefaultJndiEnvironmentAvailable()) {
+		if (jndiPresent && JndiLocatorDelegate.isDefaultJndiEnvironmentAvailable()) {
 			propertySources.addLast(new JndiPropertySource(JNDI_PROPERTY_SOURCE_NAME));
 		}
 		super.customizePropertySources(propertySources);

src/checkstyle/checkstyle.xml

@@ -13,9 +13,7 @@
 		<property name="headerCopyrightPattern" value="20\d\d-20\d\d"/>
 		<property name="packageInfoHeaderType" value="none"/>
 	</module>
-	<module name="com.puppycrawl.tools.checkstyle.checks.NewlineAtEndOfFileCheck">
-		<property name="lineSeparator" value="lf"/>
-	</module>
+	<module name="com.puppycrawl.tools.checkstyle.checks.NewlineAtEndOfFileCheck"/>
 
 	<!-- TreeWalker Checks -->
 	<module name="com.puppycrawl.tools.checkstyle.TreeWalker">