Polishing

spring-context/src/main/java/org/springframework/cache/CacheManager.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -20,22 +20,27 @@ import java.util.Collection;
 
 /**
  * Spring's central cache manager SPI.
- * Allows for retrieving named {@link Cache} regions.
+ *
+ * <p>Allows for retrieving named {@link Cache} regions.
  *
  * @author Costin Leau
+ * @author Sam Brannen
  * @since 3.1
  */
 public interface CacheManager {
 
 	/**
-	 * Return the cache associated with the given name.
+	 * Get the cache associated with the given name.
+	 * <p>Note that the cache may be lazily created at runtime if the
+	 * native provider supports it.
 	 * @param name the cache identifier (must not be {@code null})
-	 * @return the associated cache, or {@code null} if none found
+	 * @return the associated cache, or {@code null} if such a cache
+	 * does not exist or could be not created
 	 */
 	Cache getCache(String name);
 
 	/**
-	 * Return a collection of the cache names known by this manager.
+	 * Get a collection of the cache names known by this manager.
 	 * @return the names of all caches known by the cache manager
 	 */
 	Collection<String> getCacheNames();

spring-context/src/main/java/org/springframework/cache/support/AbstractCacheManager.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -171,15 +171,15 @@ public abstract class AbstractCacheManager implements CacheManager, Initializing
 	}
 
 	/**
-	 * Return a missing cache with the specified {@code name} or {@code null} if
-	 * such cache does not exist or could not be created on the fly.
-	 * <p>Some caches may be created at runtime if the native provider supports
-	 * it. If a lookup by name does not yield any result, a subclass gets a chance
-	 * to register such a cache at runtime. The returned cache will be automatically
-	 * added to this instance.
+	 * Return a missing cache with the specified {@code name}, or {@code null} if
+	 * such a cache does not exist or could not be created on demand.
+	 * <p>Caches may be lazily created at runtime if the native provider supports it.
+	 * If a lookup by name does not yield any result, an {@code AbstractCacheManager}
+	 * subclass gets a chance to register such a cache at runtime. The returned cache
+	 * will be automatically added to this cache manager.
 	 * @param name the name of the cache to retrieve
-	 * @return the missing cache or {@code null} if no such cache exists or could be
-	 * created
+	 * @return the missing cache, or {@code null} if no such cache exists or could be
+	 * created on demand
 	 * @since 4.1
 	 * @see #getCache(String)
 	 */

spring-context/src/main/java/org/springframework/context/MessageSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -24,10 +24,10 @@ import java.util.Locale;
  *
  * <p>Spring provides two out-of-the-box implementations for production:
  * <ul>
- * <li>{@link org.springframework.context.support.ResourceBundleMessageSource},
- * built on top of the standard {@link java.util.ResourceBundle}
- * <li>{@link org.springframework.context.support.ReloadableResourceBundleMessageSource},
- * being able to reload message definitions without restarting the VM
+ * <li>{@link org.springframework.context.support.ResourceBundleMessageSource}: built
+ * on top of the standard {@link java.util.ResourceBundle}, sharing its limitations.
+ * <li>{@link org.springframework.context.support.ReloadableResourceBundleMessageSource}:
+ * highly configurable, in particular with respect to reloading message definitions.
  * </ul>
  *
  * @author Rod Johnson
@@ -39,29 +39,33 @@ public interface MessageSource {
 
 	/**
 	 * Try to resolve the message. Return default message if no message was found.
-	 * @param code the code to lookup up, such as 'calculator.noRateSet'. Users of
-	 * this class are encouraged to base message names on the relevant fully
-	 * qualified class name, thus avoiding conflict and ensuring maximum clarity.
+	 * @param code the message code to look up, e.g. 'calculator.noRateSet'.
+	 * MessageSource users are encouraged to base message names on qualified class
+	 * or package names, avoiding potential conflicts and ensuring maximum clarity.
 	 * @param args an array of arguments that will be filled in for params within
 	 * the message (params look like "{0}", "{1,date}", "{2,time}" within a message),
-	 * or {@code null} if none.
+	 * or {@code null} if none
 	 * @param defaultMessage a default message to return if the lookup fails
 	 * @param locale the locale in which to do the lookup
-	 * @return the resolved message if the lookup was successful;
-	 * otherwise the default message passed as a parameter
+	 * @return the resolved message if the lookup was successful, otherwise
+	 * the default message passed as a parameter (which may be {@code null})
+	 * @see #getMessage(MessageSourceResolvable, Locale)
 	 * @see java.text.MessageFormat
 	 */
 	String getMessage(String code, Object[] args, String defaultMessage, Locale locale);
 
 	/**
 	 * Try to resolve the message. Treat as an error if the message can't be found.
-	 * @param code the code to lookup up, such as 'calculator.noRateSet'
+	 * @param code the message code to look up, e.g. 'calculator.noRateSet'.
+	 * MessageSource users are encouraged to base message names on qualified class
+	 * or package names, avoiding potential conflicts and ensuring maximum clarity.
 	 * @param args an array of arguments that will be filled in for params within
 	 * the message (params look like "{0}", "{1,date}", "{2,time}" within a message),
-	 * or {@code null} if none.
+	 * or {@code null} if none
 	 * @param locale the locale in which to do the lookup
-	 * @return the resolved message
-	 * @throws NoSuchMessageException if the message wasn't found
+	 * @return the resolved message (never {@code null})
+	 * @throws NoSuchMessageException if no corresponding message was found
+	 * @see #getMessage(MessageSourceResolvable, Locale)
 	 * @see java.text.MessageFormat
 	 */
 	String getMessage(String code, Object[] args, Locale locale) throws NoSuchMessageException;
@@ -73,9 +77,15 @@ public interface MessageSource {
 	 * since at the time of calling this method we aren't able to determine if the
 	 * {@code defaultMessage} property of the resolvable is {@code null} or not.
 	 * @param resolvable the value object storing attributes required to resolve a message
+	 * (may include a default message)
 	 * @param locale the locale in which to do the lookup
-	 * @return the resolved message
-	 * @throws NoSuchMessageException if the message wasn't found
+	 * @return the resolved message (never {@code null} since even a
+	 * {@code MessageSourceResolvable}-provided default message needs to be non-null)
+	 * @throws NoSuchMessageException if no corresponding message was found
+	 * (and no default message was provided by the {@code MessageSourceResolvable})
+	 * @see MessageSourceResolvable#getCodes()
+	 * @see MessageSourceResolvable#getArguments()
+	 * @see MessageSourceResolvable#getDefaultMessage()
 	 * @see java.text.MessageFormat
 	 */
 	String getMessage(MessageSourceResolvable resolvable, Locale locale) throws NoSuchMessageException;