8.国际化

1.国际化：是开发支持多语言和数据格式的应用程序技术

2.本地化：这是将国际化应用程序改成支持特定语言区域（locale）的技术

1.语言区域

java.util.Locale类表示一个语言区域

public Locale(java.lang.String language)

public Locale(java.lang.String language,java.lang.String country)

public Locale(java.lang.String language,java.lang.String country,java.lang.String variant)

Locale locale = new Locale("en","CA");

Locale locale = Locale.CANADA._FRENCH;

Locale locale = Locale.getDefaule();

2.国际化SpringMVC应用程序

1.将文本元件隔离成属性文件

2.选择和读取正确的属性文件

2.1 将文本文件格里成属性文件

每个文件都包含KEY/VALUE，并且KEY唯一

KEY始终是字符串，VALUE可以是字符串，也可以是任意对象

java.util.ResourceBundle类

它能使你轻松地选择和读取特定于用户语言区域的属性，以及查找值

命名方式：

基准名_语言码_国家码

MyResources_en_US.properties

2.2 选择和读取正确的属性文件

public static ResourceBundle getBundle(java.lang.String baseName);

public static ResourceBundle getBundle(java.lang.String baseName,Locale locale);

ResourceBundle rb = ResourceBundle.getBundle("MyResources",Locale.US);

利用ResourceBundle类的getString()方法传入一个key

public java.lang.String getString(java.lang.String key);

在SpringMVC，不直接使用ResourceBundle，而是利用messageSource bean告诉SpringMVC

将要将属性文件保存在哪里

1.使用ReloadableResourceBundleMessageSource在应用程序目录下搜索这些属性文件

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

2.而使用ResourceBundleMessageSource时，属性文件则必须放在类路径，WEB-INF/class下

1     <bean id="messageSource" 
2             class="org.springframework.context.support.ResourceResourceBundleMessageSource">
3         <property name="basename" value="/WEB-INF/resource/messages" />
4     </bean>

3.告诉SpringMVC使用哪个语言区域

指定使用哪个语言区域

 <bean id="localResolver" class="org.springframework.web.servlet.i81n.AcceptHeaderLocaleResolver'> 2 </bean> 

4.使用message标签

<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>

5.范例

<?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:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd     
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <context:component-scan base-package="app10a.controller" />
    <context:component-scan base-package="app10a.formatter" />

    <mvc:annotation-driven conversion-service="conversionService" />

    <mvc:resources mapping="/css/**" location="/css/" />
    <mvc:resources mapping="/*.html" location="/" />

    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>

    <bean id="conversionService"
        class="org.springframework.format.support.FormattingConversionServiceFactoryBean">

        <property name="formatters">
            <set>
                <bean class="app10a.formatter.DateFormatter">
                    <constructor-arg type="java.lang.String" value="MM-dd-yyyy" />
                </bean>
            </set>
        </property>
    </bean>

    <bean id="messageSource"
        class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
        <property name="basenames" >
            <list>
                <value>/WEB-INF/resource/messages</value>
                <value>/WEB-INF/resource/labels</value>
            </list>
        </property>
    </bean>

    <bean id="localeResolver"
        class="org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver">
    </bean>


</beans>

messageSource:实现国际化

localeResolver:利用localeResolver Bean利用AcceptHeaderLocaleResolver类实现消息的本地化

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE HTML>
<html>
<head>
<title><spring:message code="page.productform.title"/></title>
<style type="text/css">@import url("<c:url value="/css/main.css"/>");</style>
</head>
<body>

<div id="global">
Current Locale : ${pageContext.response.locale}
<br/>
accept-language header: ${header["accept-language"]}

<form:form commandName="product" action="product_save" method="post">
    <fieldset>
        <legend><spring:message code="form.name"/></legend>
        <p>
            <label for="name"><spring:message code="label.productName" text="default text" />:</label>
            <form:input id="name" path="name" cssErrorClass="error"/>
            <form:errors path="name" cssClass="error"/>
        </p>
        <p>
            <label for="description"><spring:message code="label.description"/>: </label>
            <form:input id="description" path="description"/>
        </p>
        <p>
            <label for="price"><spring:message code="label.price" text="default text" />: </label>
            <form:input id="price" path="price" cssErrorClass="error"/>
        </p>
        <p id="buttons">
            <input id="reset" type="reset" tabindex="4" 
                value="<spring:message code="button.reset"/>">
            <input id="submit" type="submit" tabindex="5" 
                value="<spring:message code="button.submit"/>">
        </p>
    </fieldset>
</form:form>
</div>
</body>
</html>

为了测试国际化，修改浏览器accept-language标签

Tools>Internet Options>General(tab)>Languages>Languages Preference中修改