如何使用Spring applicationContext從messageSource中檢索消息？

Question

這裏是我的WEB-INF/applicationContext.xml中：

<bean id="messageSource" 
    class="org.springframework.context.support.ReloadableResourceBundleMessageSource"> 
    <property name="basename" value="WEB-INF/resources/messages"/> 
    <property name="defaultEncoding" value="UTF-8" /> 
</bean> 

<bean id="configurationService" class="com.services.ConfigurationService"/> 
<bean id="companyService" class="com.services.CompanyService"/> 
<bean id="messageService" class="com.services.MessageService"/> 

它是在JSP中正常使用（春天：消息）。問題是我無法檢索我的MessageService中的消息。我嘗試了兩種不同的方法：第一種方法（請參閱下面的代碼）通過實施org.springframework.context.ApplicationContextAware來讓我的MessageService「知道」上下文。上下文在初始化期間由Spring加載，但是當我嘗試在名稱「messageResource」下查找bean時，applicationContext.getBean("messageSource")返回null。

package com.services; 

import java.util.Locale; 
import org.springframework.beans.BeansException; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.context.ApplicationContext; 
import org.springframework.context.ApplicationContextAware; 
import org.springframework.context.i18n.LocaleContextHolder; 
import org.springframework.context.support.ReloadableResourceBundleMessageSource; 

public class MessageService implements ApplicationContextAware{ 

/** MessageService Instance */ 
private static MessageService instance = null; 

/** Spring Message source*/ 
private ReloadableResourceBundleMessageSource messageSource; 

/** Application context */ 
private ApplicationContext applicationContext; 

/** Return MessageService instance */ 
public final static MessageService getInstance() 
{ 
    if (MessageService.instance==null) 
    { 
     synchronized(MessageService.class) 
     { 
      if (MessageService.instance==null) 
       MessageService.instance = new MessageService(); 

     } 
    } 
    return instance; 
} 


/** Return a message */  
public String getMessage(String messageId) 
{ 
    messageSource = (ReloadableResourceBundleMessageSource)applicationContext.getBean("messageSource"); 
    Locale locale = LocaleContextHolder.getLocale(); 
    return messageSource.getMessage(messageId,null, locale); 
} 

@Override 
@Autowired 
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { 
    this.applicationContext = applicationContext; 

} 
} 

第二種方法是加載方面，我國MessageService使用FileSystemXmlApplicationContext英寸applicationContext.getBean("messageSource")不再返回null，但messageSource.getMessage(messageId,null, locale)找不到任何消息（NoSuchMessageException）。這些消息當然存在於我的.properties中

這兩個問題看起來都像上下文問題，但我無法弄清楚在.jsp和java類中使用相同的.properties文件。另外，我希望在初始化期間在應用程序中加載一次消息，而不必每次在課堂中都需要加載它們。感謝您的幫助 ！

Answer 1

我終於想通過將我的.properties移動到classpath中的一個目錄中。對於那些誰有興趣：

<bean id="messageSource" 
class="org.springframework.context.support.ResourceBundleMessageSource"> 
    <property name="basename" value="resources/language/messages"/> 
    <property name="defaultEncoding" value="UTF-8" /> 
</bean> 

<bean id="messageService" class="com.services.MessageService" factory-method="getInstance"/> 

MessageService

package com.services; 

import java.util.Locale; 

import org.springframework.beans.BeansException; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.context.ApplicationContext; 
import org.springframework.context.ApplicationContextAware; 
import org.springframework.context.i18n.LocaleContextHolder; 
import org.springframework.context.support.ResourceBundleMessageSource; 

public class MessageService implements ApplicationContextAware{ 

/** MessageService Instance */ 
private static MessageService instance = null; 

/** Spring Message source*/ 
private ResourceBundleMessageSource messageSource; 

/** Application context */ 
private ApplicationContext applicationContext; 

/** Return MessageService instance */ 
public final static MessageService getInstance() 
{ 
    if (MessageService.instance==null) 
    { 
     synchronized(MessageService.class) 
     { 
      if (MessageService.instance==null) 
       MessageService.instance = new MessageService(); 

     } 
    } 
    return instance; 
} 


/** Return a message */  
public String getMessage(String messageId) 
{ 
    messageSource = (ResourceBundleMessageSource) applicationContext.getBean("messageSource"); 
    Locale locale = LocaleContextHolder.getLocale(); 
    return messageSource.getMessage(messageId,null, locale); 
} 


@Override 
@Autowired 
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { 
    this.applicationContext = applicationContext; 

} 
} 

注：此代碼不能與 ReloadableResourceBundleMessageSource工作。 它試圖找到資源的方式似乎不是ResourceBundleMessageSource的方式。