spring提供了三个MessageSource实现

• ResourceBundleMessageSource
• ReloadableResourceBundleMessageSource
• StaticMessageSource

要利用ApplicationContext对MessageSource的支持，必须定义一个MessageSource bean，并且命名为messageSource

源码chapter04/message-source

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans.xsd
         http://www.springframework.org/schema/util
         http://www.springframework.org/schema/util/spring-util.xsd">

    <bean id="messageSource" 
          class="org.springframework.context.support.ResourceBundleMessageSource"
      p:basenames-ref="basenames"/>

    <util:list id="basenames">
        <value>buttons</value>
        <value>labels</value>
    </util:list>
</beans>

package com.apress.prospring5.ch4;

import java.util.Locale;

import org.springframework.context.support.GenericXmlApplicationContext;

public class MessageSourceDemo {
    public static void main(String... args) {
        GenericXmlApplicationContext ctx = new GenericXmlApplicationContext();
        ctx.load("classpath:spring/app-context-xml.xml");
        ctx.refresh();

        Locale english = Locale.ENGLISH;
        Locale german = new Locale("de", "DE");

        System.out.println(ctx.getMessage("msg", null, english));
        System.out.println(ctx.getMessage("msg", null, german));

        System.out.println(ctx.getMessage("nameMsg", new Object[] { "John",
                "Mayer" }, english));
        System.out.println(ctx.getMessage("nameMsg", new Object[] { "John",
                "Mayer" }, german));

        ctx.close();
    }
}

labels_en.properties文件

msg=Mein dummer Mund hat mich in Schwierigkeiten gebracht
nameMsg=Mein Name ist {0} {1}

labels_en.properties文件

msg=My stupid mouth has got me in trouble
nameMsg=My name is {0} {1}