org.springframework.context.support

Class ResourceBundleMessageSource

java.lang.Object

org.springframework.context.support.MessageSourceSupport

org.springframework.context.support.AbstractMessageSource

org.springframework.context.support.AbstractResourceBasedMessageSource

org.springframework.context.support.ResourceBundleMessageSource

All Implemented Interfaces:

Aware, BeanClassLoaderAware, HierarchicalMessageSource, MessageSource

public class ResourceBundleMessageSource
extends AbstractResourceBasedMessageSource
implements BeanClassLoaderAware

MessageSource implementation that accesses resource bundles using specified basenames. This class relies on the underlying JDK's ResourceBundle implementation, in combination with the JDK's standard message parsing provided by MessageFormat.

This MessageSource caches both the accessed ResourceBundle instances and the generated MessageFormats for each message. It also implements rendering of no-arg messages without MessageFormat, as supported by the AbstractMessageSource base class. The caching provided by this MessageSource is significantly faster than the built-in caching of the java.util.ResourceBundle class.

The basenames follow ResourceBundle conventions: essentially, a fully-qualified classpath location. If it doesn't contain a package qualifier (such as org.mypackage), it will be resolved from the classpath root. Note that the JDK's standard ResourceBundle treats dots as package separators: This means that "test.theme" is effectively equivalent to "test/theme".

On the classpath, bundle resources will be read with the locally configured encoding: by default, ISO-8859-1; consider switching this to UTF-8, or to null for the platform default encoding. On the JDK 9+ module path where locally provided ResourceBundle.Control handles are not supported, this MessageSource always falls back to ResourceBundle.getBundle(java.lang.String) retrieval with the platform default encoding: UTF-8 with a ISO-8859-1 fallback on JDK 9+ (configurable through the "java.util.PropertyResourceBundle.encoding" system property). Note that loadBundle(Reader)/loadBundle(InputStream) won't be called in this case either, effectively ignoring overrides in subclasses. Consider implementing a JDK 9 java.util.spi.ResourceBundleProvider instead.

Author:

Rod Johnson, Juergen Hoeller

See Also:

AbstractResourceBasedMessageSource.setBasenames(java.lang.String...), ReloadableResourceBundleMessageSource, ResourceBundle, MessageFormat

Field Summary

Fields inherited from class org.springframework.context.support.MessageSourceSupport

logger

Constructor Summary

Constructors

Constructor and Description
ResourceBundleMessageSource()

Method Summary

Modifier and Type	Method and Description
protected ResourceBundle	doGetBundle(String basename, Locale locale) Obtain the resource bundle for the given basename and Locale.
protected ClassLoader	getBundleClassLoader() Return the ClassLoader to load resource bundles with.
protected MessageFormat	getMessageFormat(ResourceBundle bundle, String code, Locale locale) Return a MessageFormat for the given bundle and code, fetching already generated MessageFormats from the cache.
protected ResourceBundle	getResourceBundle(String basename, Locale locale) Return a ResourceBundle for the given basename and code, fetching already generated MessageFormats from the cache.
protected String	getStringOrNull(ResourceBundle bundle, String key) Efficiently retrieve the String value for the specified key, or return null if not found.
protected ResourceBundle	loadBundle(InputStream inputStream) Load a property-based resource bundle from the given input stream, picking up the default properties encoding on JDK 9+.
protected ResourceBundle	loadBundle(Reader reader) Load a property-based resource bundle from the given reader.
protected MessageFormat	resolveCode(String code, Locale locale) Resolves the given message code as key in the registered resource bundles, using a cached MessageFormat instance per message code.
protected String	resolveCodeWithoutArguments(String code, Locale locale) Resolves the given message code as key in the registered resource bundles, returning the value found in the bundle as-is (without MessageFormat parsing).
void	setBeanClassLoader(ClassLoader classLoader) Callback that supplies the bean class loader to a bean instance.
void	setBundleClassLoader(ClassLoader classLoader) Set the ClassLoader to load resource bundles with.
String	toString() Show the configuration of this MessageSource.

Methods inherited from class org.springframework.context.support.AbstractResourceBasedMessageSource

addBasenames, getBasenameSet, getCacheMillis, getDefaultEncoding, isFallbackToSystemLocale, setBasename, setBasenames, setCacheMillis, setCacheSeconds, setDefaultEncoding, setFallbackToSystemLocale

Methods inherited from class org.springframework.context.support.AbstractMessageSource

getCommonMessages, getDefaultMessage, getDefaultMessage, getMessage, getMessage, getMessage, getMessageFromParent, getMessageInternal, getParentMessageSource, isUseCodeAsDefaultMessage, resolveArguments, setCommonMessages, setParentMessageSource, setUseCodeAsDefaultMessage

Methods inherited from class org.springframework.context.support.MessageSourceSupport

createMessageFormat, formatMessage, isAlwaysUseMessageFormat, renderDefaultMessage, setAlwaysUseMessageFormat

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ResourceBundleMessageSource

public ResourceBundleMessageSource()

Method Detail

setBundleClassLoader

public void setBundleClassLoader(ClassLoader classLoader)

Set the ClassLoader to load resource bundles with.

Default is the containing BeanFactory's bean ClassLoader, or the default ClassLoader determined by ClassUtils.getDefaultClassLoader() if not running within a BeanFactory.

getBundleClassLoader

@Nullable
protected ClassLoader getBundleClassLoader()

Return the ClassLoader to load resource bundles with.

Default is the containing BeanFactory's bean ClassLoader.

See Also:

setBundleClassLoader(java.lang.ClassLoader)

setBeanClassLoader

public void setBeanClassLoader(ClassLoader classLoader)

Description copied from interface: BeanClassLoaderAware

Callback that supplies the bean class loader to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean's InitializingBean.afterPropertiesSet() method or a custom init-method.

Specified by:

setBeanClassLoader in interface BeanClassLoaderAware

Parameters:

classLoader - the owning class loader

resolveCodeWithoutArguments

protected String resolveCodeWithoutArguments(String code,
                                             Locale locale)

Resolves the given message code as key in the registered resource bundles, returning the value found in the bundle as-is (without MessageFormat parsing).

Overrides:

resolveCodeWithoutArguments in class AbstractMessageSource

Parameters:

code - the code of the message to resolve

locale - the locale to resolve the code for (subclasses are encouraged to support internationalization)

Returns:

the message String, or null if not found

See Also:

AbstractMessageSource.resolveCode(java.lang.String, java.util.Locale), MessageFormat

resolveCode

@Nullable
protected MessageFormat resolveCode(String code,
                                              Locale locale)

Resolves the given message code as key in the registered resource bundles, using a cached MessageFormat instance per message code.

Specified by:

resolveCode in class AbstractMessageSource

Parameters:

code - the code of the message to resolve

locale - the locale to resolve the code for (subclasses are encouraged to support internationalization)

Returns:

the MessageFormat for the message, or null if not found

See Also:

AbstractMessageSource.resolveCodeWithoutArguments(String, java.util.Locale)

getResourceBundle

@Nullable
protected ResourceBundle getResourceBundle(String basename,
                                                     Locale locale)

Return a ResourceBundle for the given basename and code, fetching already generated MessageFormats from the cache.

Parameters:

basename - the basename of the ResourceBundle

locale - the Locale to find the ResourceBundle for

Returns:

the resulting ResourceBundle, or null if none found for the given basename and Locale

doGetBundle

protected ResourceBundle doGetBundle(String basename,
                                     Locale locale)
                              throws MissingResourceException

Obtain the resource bundle for the given basename and Locale.

Parameters:

basename - the basename to look for

locale - the Locale to look for

Returns:

the corresponding ResourceBundle

Throws:

MissingResourceException - if no matching bundle could be found

See Also:

ResourceBundle.getBundle(String, Locale, ClassLoader), getBundleClassLoader()

loadBundle

protected ResourceBundle loadBundle(Reader reader)
                             throws IOException

Load a property-based resource bundle from the given reader.

This will be called in case of a "defaultEncoding", including ResourceBundleMessageSource's default ISO-8859-1 encoding. Note that this method can only be called with a ResourceBundle.Control: When running on the JDK 9+ module path where such control handles are not supported, any overrides in custom subclasses will effectively get ignored.

The default implementation returns a PropertyResourceBundle.

Parameters:

reader - the reader for the target resource

Returns:

the fully loaded bundle

Throws:

IOException - in case of I/O failure

Since:

4.2

See Also:

loadBundle(InputStream), PropertyResourceBundle.PropertyResourceBundle(Reader)

loadBundle

protected ResourceBundle loadBundle(InputStream inputStream)
                             throws IOException

Load a property-based resource bundle from the given input stream, picking up the default properties encoding on JDK 9+.

This will only be called with "defaultEncoding" set to null, explicitly enforcing the platform default encoding (which is UTF-8 with a ISO-8859-1 fallback on JDK 9+ but configurable through the "java.util.PropertyResourceBundle.encoding" system property). Note that this method can only be called with a ResourceBundle.Control: When running on the JDK 9+ module path where such control handles are not supported, any overrides in custom subclasses will effectively get ignored.

The default implementation returns a PropertyResourceBundle.

Parameters:

inputStream - the input stream for the target resource

Returns:

the fully loaded bundle

Throws:

IOException - in case of I/O failure

Since:

5.1

See Also:

loadBundle(Reader), PropertyResourceBundle.PropertyResourceBundle(InputStream)

getMessageFormat

@Nullable
protected MessageFormat getMessageFormat(ResourceBundle bundle,
                                                   String code,
                                                   Locale locale)
                                            throws MissingResourceException

Return a MessageFormat for the given bundle and code, fetching already generated MessageFormats from the cache.

Parameters:

bundle - the ResourceBundle to work on

code - the message code to retrieve

locale - the Locale to use to build the MessageFormat

Returns:

the resulting MessageFormat, or null if no message defined for the given code

Throws:

MissingResourceException - if thrown by the ResourceBundle

getStringOrNull

@Nullable
protected String getStringOrNull(ResourceBundle bundle,
                                           String key)

Efficiently retrieve the String value for the specified key, or return null if not found.

As of 4.2, the default implementation checks containsKey before it attempts to call getString (which would require catching MissingResourceException for key not found).

Can be overridden in subclasses.

Parameters:

bundle - the ResourceBundle to perform the lookup in

key - the key to look up

Returns:

the associated value, or null if none

Since:

4.2

See Also:

ResourceBundle.getString(String), ResourceBundle.containsKey(String)

toString

public String toString()

Show the configuration of this MessageSource.

Overrides:

toString in class Object