org.apache.struts.util
Class MessageResources

java.lang.Object
  org.apache.struts.util.MessageResources

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

PropertyMessageResources

public abstract class MessageResources
extends Object
implements Serializable

General purpose abstract class that describes an API for retrieving Locale-sensitive messages from underlying resource locations of an unspecified design, and optionally utilizing the MessageFormat class to produce internationalized messages with parametric replacement.

Calls to getMessage() variants without a Locale argument are presumed to be requesting a message string in the default Locale for this JVM.

Calls to getMessage() with an unknown key, or an unknown Locale will return null if the returnNull property is set to true. Otherwise, a suitable error message will be returned instead.

IMPLEMENTATION NOTE - Classes that extend this class must be Serializable so that instances may be used in distributable application server environments.

Version:

$Rev: 471754 $ $Date: 2005-08-29 23:57:50 -0400 (Mon, 29 Aug 2005) $

See Also:

Serialized Form

Field Summary

protected String	config The configuration parameter used to initialize this MessageResources.
protected static MessageResourcesFactory	defaultFactory The default MessageResourcesFactory used to create MessageResources instances.
protected Locale	defaultLocale The default Locale for our environment.
protected MessageResourcesFactory	factory The MessageResourcesFactory that created this instance.
protected HashMap	formats The set of previously created MessageFormat objects, keyed by the key computed in messageKey().
protected static Log	log Commons Logging instance.
protected boolean	returnNull Indicate is a null is returned instead of an error message string when an unknown Locale or key is requested.

Constructor Summary

MessageResources(MessageResourcesFactory factory, String config)
Construct a new MessageResources according to the specified parameters.

MessageResources(MessageResourcesFactory factory, String config, boolean returnNull)
Construct a new MessageResources according to the specified parameters.

Method Summary

protected String	escape(String string) Escape any single quote characters that are included in the specified message string.
String	getConfig() The configuration parameter used to initialize this MessageResources.
MessageResourcesFactory	getFactory() The MessageResourcesFactory that created this instance.
abstract String	getMessage(Locale locale, String key) Returns a text message for the specified key, for the default Locale.
String	getMessage(Locale locale, String key, Object arg0) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(Locale locale, String key, Object[] args) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(Locale locale, String key, Object arg0, Object arg1) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(Locale locale, String key, Object arg0, Object arg1, Object arg2) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(Locale locale, String key, Object arg0, Object arg1, Object arg2, Object arg3) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(String key) Returns a text message for the specified key, for the default Locale.
String	getMessage(String key, Object arg0) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(String key, Object[] args) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(String key, Object arg0, Object arg1) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(String key, Object arg0, Object arg1, Object arg2) Returns a text message after parametric replacement of the specified parameter placeholders.
String	getMessage(String key, Object arg0, Object arg1, Object arg2, Object arg3) Returns a text message after parametric replacement of the specified parameter placeholders.
static MessageResources	getMessageResources(String config) Create and return an instance of MessageResources for the created by the default MessageResourcesFactory.
boolean	getReturnNull() Indicates that a null is returned instead of an error message string if an unknown Locale or key is requested.
boolean	isEscape() Indicates whether 'escape processing' should be performed on the error message string.
boolean	isPresent(Locale locale, String key) Return true if there is a defined message for the specified key in the specified Locale.
boolean	isPresent(String key) Return true if there is a defined message for the specified key in the system default locale.
protected String	localeKey(Locale locale) Compute and return a key to be used in caching information by a Locale.
void	log(String message) Log a message to the Writer that has been configured for our use.
void	log(String message, Throwable throwable) Log a message and exception to the Writer that has been configured for our use.
protected String	messageKey(Locale locale, String key) Compute and return a key to be used in caching information by Locale and message key.
protected String	messageKey(String localeKey, String key) Compute and return a key to be used in caching information by locale key and message key.
void	setEscape(boolean escape) Set whether 'escape processing' should be performed on the error message string.
void	setReturnNull(boolean returnNull) Indicates that a null is returned instead of an error message string if an unknown Locale or key is requested.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static Log log

Commons Logging instance.

defaultFactory

protected static MessageResourcesFactory defaultFactory

The default MessageResourcesFactory used to create MessageResources instances.

config

protected String config

The configuration parameter used to initialize this MessageResources.

defaultLocale

protected Locale defaultLocale

The default Locale for our environment.

factory

protected MessageResourcesFactory factory

The MessageResourcesFactory that created this instance.

formats

protected HashMap formats

The set of previously created MessageFormat objects, keyed by the key computed in messageKey().

returnNull

protected boolean returnNull

Indicate is a null is returned instead of an error message string when an unknown Locale or key is requested.

Constructor Detail

MessageResources

public MessageResources(MessageResourcesFactory factory,
                        String config)

Construct a new MessageResources according to the specified parameters.

Parameters:

factory - The MessageResourcesFactory that created us

config - The configuration parameter for this MessageResources

MessageResources

public MessageResources(MessageResourcesFactory factory,
                        String config,
                        boolean returnNull)

Construct a new MessageResources according to the specified parameters.

Parameters:

factory - The MessageResourcesFactory that created us

config - The configuration parameter for this MessageResources

returnNull - The returnNull property we should initialize with

Method Detail

getConfig

public String getConfig()

The configuration parameter used to initialize this MessageResources.

Returns:

parameter used to initialize this MessageResources

getFactory

public MessageResourcesFactory getFactory()

The MessageResourcesFactory that created this instance.

Returns:

MessageResourcesFactory that created instance

getReturnNull

public boolean getReturnNull()

Indicates that a null is returned instead of an error message string if an unknown Locale or key is requested.

Returns:

true if null is returned if unknown key or locale is requested

setReturnNull

public void setReturnNull(boolean returnNull)

Indicates that a null is returned instead of an error message string if an unknown Locale or key is requested.

Parameters:

returnNull - true Indicates that a null is returned if an unknown Locale or key is requested.

isEscape

public boolean isEscape()

Indicates whether 'escape processing' should be performed on the error message string.

Since:

Struts 1.2.8

setEscape

public void setEscape(boolean escape)

Set whether 'escape processing' should be performed on the error message string.

Since:

Struts 1.2.8

getMessage

public String getMessage(String key)

Returns a text message for the specified key, for the default Locale.

Parameters:

key - The message key to look up

getMessage

public String getMessage(String key,
                         Object[] args)

Returns a text message after parametric replacement of the specified parameter placeholders.

Parameters:

key - The message key to look up

args - An array of replacement parameters for placeholders

getMessage

public String getMessage(String key,
                         Object arg0)

Returns a text message after parametric replacement of the specified parameter placeholders.

Parameters:

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

getMessage

public String getMessage(String key,
                         Object arg0,
                         Object arg1)

Returns a text message after parametric replacement of the specified parameter placeholders.

Parameters:

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

getMessage

public String getMessage(String key,
                         Object arg0,
                         Object arg1,
                         Object arg2)

Returns a text message after parametric replacement of the specified parameter placeholders.

Parameters:

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

arg2 - The replacement for placeholder {2} in the message

getMessage

public String getMessage(String key,
                         Object arg0,
                         Object arg1,
                         Object arg2,
                         Object arg3)

Returns a text message after parametric replacement of the specified parameter placeholders.

Parameters:

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

arg2 - The replacement for placeholder {2} in the message

arg3 - The replacement for placeholder {3} in the message

getMessage

public abstract String getMessage(Locale locale,
                                  String key)

Returns a text message for the specified key, for the default Locale. A null string result will be returned by this method if no relevant message resource is found for this key or Locale, if the returnNull property is set. Otherwise, an appropriate error message will be returned.

This method must be implemented by a concrete subclass.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

getMessage

public String getMessage(Locale locale,
                         String key,
                         Object[] args)

Returns a text message after parametric replacement of the specified parameter placeholders. A null string result will be returned by this method if no resource bundle has been configured.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

args - An array of replacement parameters for placeholders

getMessage

public String getMessage(Locale locale,
                         String key,
                         Object arg0)

Returns a text message after parametric replacement of the specified parameter placeholders. A null string result will never be returned by this method.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

getMessage

public String getMessage(Locale locale,
                         String key,
                         Object arg0,
                         Object arg1)

Returns a text message after parametric replacement of the specified parameter placeholders. A null string result will never be returned by this method.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

getMessage

public String getMessage(Locale locale,
                         String key,
                         Object arg0,
                         Object arg1,
                         Object arg2)

Returns a text message after parametric replacement of the specified parameter placeholders. A null string result will never be returned by this method.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

arg2 - The replacement for placeholder {2} in the message

getMessage

public String getMessage(Locale locale,
                         String key,
                         Object arg0,
                         Object arg1,
                         Object arg2,
                         Object arg3)

Returns a text message after parametric replacement of the specified parameter placeholders. A null string result will never be returned by this method.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

arg0 - The replacement for placeholder {0} in the message

arg1 - The replacement for placeholder {1} in the message

arg2 - The replacement for placeholder {2} in the message

arg3 - The replacement for placeholder {3} in the message

isPresent

public boolean isPresent(String key)

Return true if there is a defined message for the specified key in the system default locale.

Parameters:

key - The message key to look up

isPresent

public boolean isPresent(Locale locale,
                         String key)

Return true if there is a defined message for the specified key in the specified Locale.

Parameters:

locale - The requested message Locale, or null for the system default Locale

key - The message key to look up

escape

protected String escape(String string)

Escape any single quote characters that are included in the specified message string.

Parameters:

string - The string to be escaped

localeKey

protected String localeKey(Locale locale)

Compute and return a key to be used in caching information by a Locale. NOTE - The locale key for the default Locale in our environment is a zero length String.

Parameters:

locale - The locale for which a key is desired

messageKey

protected String messageKey(Locale locale,
                            String key)

Compute and return a key to be used in caching information by Locale and message key.

Parameters:

locale - The Locale for which this format key is calculated

key - The message key for which this format key is calculated

messageKey

protected String messageKey(String localeKey,
                            String key)

Compute and return a key to be used in caching information by locale key and message key.

Parameters:

localeKey - The locale key for which this cache key is calculated

key - The message key for which this cache key is calculated

getMessageResources

public static MessageResources getMessageResources(String config)

Create and return an instance of MessageResources for the created by the default MessageResourcesFactory.

Parameters:

config - Configuration parameter for this message bundle.

log

public void log(String message)

Log a message to the Writer that has been configured for our use.

Parameters:

message - The message to be logged

log

public void log(String message,
                Throwable throwable)

Log a message and exception to the Writer that has been configured for our use.

Parameters:

message - The message to be logged

throwable - The exception to be logged