org.springframework.context.support

类 AbstractMessageSource

java.lang.Object

org.springframework.context.support.MessageSourceSupport

org.springframework.context.support.AbstractMessageSource

所有已实现的接口:

HierarchicalMessageSource, MessageSource

直接已知子类:

AbstractResourceBasedMessageSource, StaticMessageSource

public abstract class AbstractMessageSource
extends MessageSourceSupport
implements HierarchicalMessageSource

Abstract implementation of the HierarchicalMessageSource interface, implementing common handling of message variants, making it easy to implement a specific strategy for a concrete MessageSource.

Subclasses must implement the abstract resolveCode(java.lang.String, java.util.Locale) method. For efficient resolution of messages without arguments, the resolveCodeWithoutArguments(java.lang.String, java.util.Locale) method should be overridden as well, resolving messages without a MessageFormat being involved.

Note: By default, message texts are only parsed through MessageFormat if arguments have been passed in for the message. In case of no arguments, message texts will be returned as-is. As a consequence, you should only use MessageFormat escaping for messages with actual arguments, and keep all other messages unescaped. If you prefer to escape all messages, set the "alwaysUseMessageFormat" flag to "true".

Supports not only MessageSourceResolvables as primary messages but also resolution of message arguments that are in turn MessageSourceResolvables themselves.

This class does not implement caching of messages per code, thus subclasses can dynamically change messages over time. Subclasses are encouraged to cache their messages in a modification-aware fashion, allowing for hot deployment of updated messages.

作者:

Juergen Hoeller, Rod Johnson

另请参阅:

resolveCode(String, java.util.Locale), resolveCodeWithoutArguments(String, java.util.Locale), MessageSourceSupport.setAlwaysUseMessageFormat(boolean), MessageFormat

字段概要

从类继承的字段 org.springframework.context.support.MessageSourceSupport

logger

构造器概要

构造器

构造器和说明
AbstractMessageSource()

方法概要

限定符和类型	方法和说明
protected Properties	getCommonMessages() Return a Properties object defining locale-independent common messages, if any.
protected String	getDefaultMessage(MessageSourceResolvable resolvable, Locale locale) Get a default message for the given MessageSourceResolvable.
protected String	getDefaultMessage(String code) Return a fallback default message for the given code, if any.
String	getMessage(MessageSourceResolvable resolvable, Locale locale) Try to resolve the message using all the attributes contained within the MessageSourceResolvable argument that was passed in.
String	getMessage(String code, Object[] args, Locale locale) Try to resolve the message.
String	getMessage(String code, Object[] args, String defaultMessage, Locale locale) Try to resolve the message.
protected String	getMessageFromParent(String code, Object[] args, Locale locale) Try to retrieve the given message from the parent MessageSource, if any.
protected String	getMessageInternal(String code, Object[] args, Locale locale) Resolve the given code and arguments as message in the given Locale, returning null if not found.
MessageSource	getParentMessageSource() Return the parent of this MessageSource, or null if none.
protected boolean	isUseCodeAsDefaultMessage() Return whether to use the message code as default message instead of throwing a NoSuchMessageException.
protected Object[]	resolveArguments(Object[] args, Locale locale) Searches through the given array of objects, finds any MessageSourceResolvable objects and resolves them.
protected abstract MessageFormat	resolveCode(String code, Locale locale) Subclasses must implement this method to resolve a message.
protected String	resolveCodeWithoutArguments(String code, Locale locale) Subclasses can override this method to resolve a message without arguments in an optimized fashion, i.e. to resolve without involving a MessageFormat.
void	setCommonMessages(Properties commonMessages) Specify locale-independent common messages, with the message code as key and the full message String (may contain argument placeholders) as value.
void	setParentMessageSource(MessageSource parent) Set the parent that will be used to try to resolve messages that this object can't resolve.
void	setUseCodeAsDefaultMessage(boolean useCodeAsDefaultMessage) Set whether to use the message code as default message instead of throwing a NoSuchMessageException.

从类继承的方法 org.springframework.context.support.MessageSourceSupport

createMessageFormat, formatMessage, isAlwaysUseMessageFormat, renderDefaultMessage, setAlwaysUseMessageFormat

从类继承的方法 java.lang.Object

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

构造器详细资料

AbstractMessageSource

public AbstractMessageSource()

方法详细资料

setParentMessageSource

public void setParentMessageSource(@Nullable
                                   MessageSource parent)

从接口复制的说明: HierarchicalMessageSource

Set the parent that will be used to try to resolve messages that this object can't resolve.

指定者:

setParentMessageSource 在接口中 HierarchicalMessageSource

参数:

parent - the parent MessageSource that will be used to resolve messages that this object can't resolve. May be null, in which case no further resolution is possible.

getParentMessageSource

@Nullable
public MessageSource getParentMessageSource()

从接口复制的说明: HierarchicalMessageSource

Return the parent of this MessageSource, or null if none.

指定者:

getParentMessageSource 在接口中 HierarchicalMessageSource

setCommonMessages

public void setCommonMessages(@Nullable
                              Properties commonMessages)

Specify locale-independent common messages, with the message code as key and the full message String (may contain argument placeholders) as value.

May also link to an externally defined Properties object, e.g. defined through a PropertiesFactoryBean.

getCommonMessages

@Nullable
protected Properties getCommonMessages()

Return a Properties object defining locale-independent common messages, if any.

setUseCodeAsDefaultMessage

public void setUseCodeAsDefaultMessage(boolean useCodeAsDefaultMessage)

Set whether to use the message code as default message instead of throwing a NoSuchMessageException. Useful for development and debugging. Default is "false".

Note: In case of a MessageSourceResolvable with multiple codes (like a FieldError) and a MessageSource that has a parent MessageSource, do not activate "useCodeAsDefaultMessage" in the parent: Else, you'll get the first code returned as message by the parent, without attempts to check further codes.

To be able to work with "useCodeAsDefaultMessage" turned on in the parent, AbstractMessageSource and AbstractApplicationContext contain special checks to delegate to the internal getMessageInternal(java.lang.String, java.lang.Object[], java.util.Locale) method if available. In general, it is recommended to just use "useCodeAsDefaultMessage" during development and not rely on it in production in the first place, though.

另请参阅:

getMessage(String, Object[], Locale), FieldError

isUseCodeAsDefaultMessage

protected boolean isUseCodeAsDefaultMessage()

Return whether to use the message code as default message instead of throwing a NoSuchMessageException. Useful for development and debugging. Default is "false".

Alternatively, consider overriding the getDefaultMessage(org.springframework.context.MessageSourceResolvable, java.util.Locale) method to return a custom fallback message for an unresolvable code.

另请参阅:

getDefaultMessage(String)

getMessage

public final String getMessage(String code,
                               @Nullable
                               Object[] args,
                               @Nullable
                               String defaultMessage,
                               Locale locale)

从接口复制的说明: MessageSource

Try to resolve the message. Return default message if no message was found.

指定者:

getMessage 在接口中 MessageSource

参数:

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.

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 null if none.

defaultMessage - a default message to return if the lookup fails

locale - the locale in which to do the lookup

返回:

the resolved message if the lookup was successful; otherwise the default message passed as a parameter

另请参阅:

MessageFormat

getMessage

public final String getMessage(String code,
                               @Nullable
                               Object[] args,
                               Locale locale)
                        throws NoSuchMessageException

从接口复制的说明: MessageSource

Try to resolve the message. Treat as an error if the message can't be found.

指定者:

getMessage 在接口中 MessageSource

参数:

code - the code to lookup up, such as 'calculator.noRateSet'

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 null if none.

locale - the locale in which to do the lookup

返回:

the resolved message

抛出:

NoSuchMessageException - if the message wasn't found

另请参阅:

MessageFormat

getMessage

public final String getMessage(MessageSourceResolvable resolvable,
                               Locale locale)
                        throws NoSuchMessageException

从接口复制的说明: MessageSource

Try to resolve the message using all the attributes contained within the MessageSourceResolvable argument that was passed in.

NOTE: We must throw a NoSuchMessageException on this method since at the time of calling this method we aren't able to determine if the defaultMessage property of the resolvable is null or not.

指定者:

getMessage 在接口中 MessageSource

参数:

resolvable - the value object storing attributes required to resolve a message

locale - the locale in which to do the lookup

返回:

the resolved message

抛出:

NoSuchMessageException - if the message wasn't found

另请参阅:

MessageFormat

getMessageInternal

@Nullable
protected String getMessageInternal(@Nullable
                                               String code,
                                               @Nullable
                                               Object[] args,
                                               @Nullable
                                               Locale locale)

Resolve the given code and arguments as message in the given Locale, returning null if not found. Does not fall back to the code as default message. Invoked by getMessage methods.

参数:

code - the code to lookup up, such as 'calculator.noRateSet'

args - array of arguments that will be filled in for params within the message

locale - the locale in which to do the lookup

返回:

the resolved message, or null if not found

另请参阅:

getMessage(String, Object[], String, Locale), getMessage(String, Object[], Locale), getMessage(MessageSourceResolvable, Locale), setUseCodeAsDefaultMessage(boolean)

getMessageFromParent

@Nullable
protected String getMessageFromParent(String code,
                                                 @Nullable
                                                 Object[] args,
                                                 Locale locale)

Try to retrieve the given message from the parent MessageSource, if any.

参数:

code - the code to lookup up, such as 'calculator.noRateSet'

args - array of arguments that will be filled in for params within the message

locale - the locale in which to do the lookup

返回:

the resolved message, or null if not found

另请参阅:

getParentMessageSource()

getDefaultMessage

@Nullable
protected String getDefaultMessage(MessageSourceResolvable resolvable,
                                              Locale locale)

Get a default message for the given MessageSourceResolvable.

This implementation fully renders the default message if available, or just returns the plain default message String if the primary message code is being used as a default message.

参数:

resolvable - the value object to resolve a default message for

locale - the current locale

返回:

the default message, or null if none

从以下版本开始:

4.3.6

另请参阅:

MessageSourceSupport.renderDefaultMessage(String, Object[], Locale), getDefaultMessage(String)

getDefaultMessage

@Nullable
protected String getDefaultMessage(String code)

Return a fallback default message for the given code, if any.

Default is to return the code itself if "useCodeAsDefaultMessage" is activated, or return no fallback else. In case of no fallback, the caller will usually receive a NoSuchMessageException from getMessage.

参数:

code - the message code that we couldn't resolve and that we didn't receive an explicit default message for

返回:

the default message to use, or null if none

另请参阅:

setUseCodeAsDefaultMessage(boolean)

resolveArguments

protected Object[] resolveArguments(@Nullable
                                    Object[] args,
                                    Locale locale)

Searches through the given array of objects, finds any MessageSourceResolvable objects and resolves them.

Allows for messages to have MessageSourceResolvables as arguments.

覆盖:

resolveArguments 在类中 MessageSourceSupport

参数:

args - array of arguments for a message

locale - the locale to resolve through

返回:

an array of arguments with any MessageSourceResolvables resolved

resolveCodeWithoutArguments

@Nullable
protected String resolveCodeWithoutArguments(String code,
                                                        Locale locale)

Subclasses can override this method to resolve a message without arguments in an optimized fashion, i.e. to resolve without involving a MessageFormat.

The default implementation does use MessageFormat, through delegating to the resolveCode(java.lang.String, java.util.Locale) method. Subclasses are encouraged to replace this with optimized resolution.

Unfortunately, java.text.MessageFormat is not implemented in an efficient fashion. In particular, it does not detect that a message pattern doesn't contain argument placeholders in the first place. Therefore, it is advisable to circumvent MessageFormat for messages without arguments.

参数:

code - the code of the message to resolve

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

返回:

the message String, or null if not found

另请参阅:

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

resolveCode

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

Subclasses must implement this method to resolve a message.

Returns a MessageFormat instance rather than a message String, to allow for appropriate caching of MessageFormats in subclasses.

Subclasses are encouraged to provide optimized resolution for messages without arguments, not involving MessageFormat. See the resolveCodeWithoutArguments(java.lang.String, java.util.Locale) javadoc for details.

参数:

code - the code of the message to resolve

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

返回:

the MessageFormat for the message, or null if not found

另请参阅:

resolveCodeWithoutArguments(String, java.util.Locale)