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如何配置国际化资源文件?
1、Action范围资源文件：在Action类文件所在的路径建立名为ActionName_language_country.properties的文件；
2、包范围资源文件：在包的根路径下建立文件名为package_language_country.properties的属性文件，一旦建立，处于该包下的所有Action都可以访问该资源文件。
注意：包范围资源文件的baseName就是package，不是Action所在的包名。
3、全局资源文件：
3.1、命名方式：basename_language_country.properties
3.2、struts.xml 中添加配置：<constant name=”struts.custom.i18n.resources” value=”baseName” />
4、国际化资源文件加载的顺序：离当前Action较近的资源文件被优先加载。
新建项目struts_05:
struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<constant name="struts.custom.i18n.resources" value="i18n"></constant>
<package name="default" namespace="/" extends="struts-default">
<action name="i18nTest" class="com.dx.struts2.i18ntest.I18nAction">
<result>/i18n.jsp</result>
</action>
</package>
</struts>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_9" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Struts 02</display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
com.dx.struts2.i18ntest.I18nAction.java
package com.dx.struts2.i18ntest;import com.opensymphony.xwork2.ActionSupport;public class I18nAction extends ActionSupport {
private static final long serialVersionUID = 1L; @Override
public String execute() throws Exception {
return SUCCESS;
}
}
index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body><a href="i18nTest" rel="external nofollow" >test</a></body>
</html>
i18n.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<s:debug></s:debug>
<s:form action="">
<s:textfield name="username" label="UserName"></s:textfield>
<s:textfield name="username" label="%{getText('username')}"></s:textfield>
<s:textfield name="username" key="username"></s:textfield>
<s:textfield name="password" key="password"></s:textfield>
<s:submit key="submit"></s:submit>
</s:form>
</body>
</html>
src下创建i18n.properties
username=UserName
password=Password
submit=Submit
、i18n_zh_CN.properties
username=\u7528\u6237\u540D
password=\u5BC6\u7801
submit=\u63D0\u4EA4
、i18n_en_US.properties
username=UserName
password=Password
submit=Submit
访问index.jsp，点击“test”连接跳转到i18n.jsp页面，并修改浏览器的“语言”，看看界面是否有变化。
在com.dx.struts2.i18ntest下创建i18n.properties
username=^UserName
password=^Password
submit=^Submit
、i18n_zh_CN.properties
username=^\u7528\u6237\u540D
password=^\u5BC6\u7801
submit=^\u63D0\u4EA4
、i18n_en_US.properties
username=^UserName
password=^Password
submit=^Submit
访问index.jsp，点击“test”连接跳转到i18n.jsp页面，并修改浏览器的“语言”，看看界面是否有变化。
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在页面上和Action类中如何访问国际化资源文件的value值
1、在Action类中：若Action实现了TextProvider接口，则可以通过调用getText()方法来获取资源文件文件中的value值；
package com.dx.struts2.i18ntest;import com.opensymphony.xwork2.ActionSupport;public class I18nAction extends ActionSupport {
private static final long serialVersionUID = 1L; @Override
public String execute() throws Exception {
String username = this.getText("username");
String password = this.getText("password");
System.out.println(username);
System.out.println(password); return SUCCESS;
}
}
备注：为什么继承ActionSupport类，因为ActionSupport实现了TextProvider接口。
2、在 jsp 页面上：可以通过s:text标签来访问资源文件中的value值；对于表单（非theme=”simple”）标签可以使用表单标签的key属性值：
2.1、若有占位符，则可以使用s:text标签中嵌套一个子标签s:param来填充占位符；
2.2、可以利用标签和OGNL表达式直接访问值栈中的属性值（对象栈、Map栈）
修改i18n.jsp的form主题theme=“simple”，发现之前的页面中的标签中的国际化信息都没有被显示，解决方案：
<s:form action="" theme="simple">
<s:textfield name="username" label="UserName"></s:textfield>
<s:text name="username" />
<s:textfield name="username" label="%{getText('username')}"></s:textfield>
<s:text name="username" />
<s:textfield name="username" key="username"></s:textfield>
<s:text name="password" />
<s:textfield name="password" key="password"></s:textfield>
<s:submit key="submit" value="%{getText('submit')}"></s:submit>
</s:form>
针对占位符解决方案一：
properties文件中：
time=Time:{0}
jsp:
<s:text name="time">
<s:param value="date"></s:param>
</s:text>
针对占位符解决方案一：
properties文件中：
time2=Time:${date}
jsp:
<s:text name="time2"></s:text>
I18nAction.java
package com.dx.struts2.i18ntest;import java.util.Arrays;
import java.util.Date;import com.opensymphony.xwork2.ActionSupport;public class I18nAction extends ActionSupport {
private static final long serialVersionUID = 1L;
private Date date = null; public Date getDate() {
return date;
} public void setDate(Date date) {
this.date = date;
} @Override
public String execute() throws Exception {
this.date = new Date(); String username = this.getText("username");
String password = this.getText("password");
String dateTime = this.getText("time", Arrays.asList(this.date));
System.out.println(username);
System.out.println(password);
System.out.println(dateTime); return SUCCESS;
}
}
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通过超链接动态加载国际化资源文件
实际上通过struts2的超级链接，被i18n拦截器拦截掉，过滤请求中是否包含参数，如果包含参数就设置国际化，并把设置信息保存在session中；
如果请求参数中不包含国际化设置，则查看session中是否已经包含，如果包含，则从session中获取国际化设置；
如果请求参数中不包含国际化设置，且session中也不包含，则从浏览器中获取国际化设置。
流程图：
查看i18n拦截器（com.opensymphony.xwork2.interceptor.I18nInterceptor.java）
/*
* Copyright 2002-2006,2009 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/package com.opensymphony.xwork2.interceptor;import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.util.LocalizedTextUtil;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;import java.util.Arrays;
import java.util.Locale;
import java.util.Map;/**
* <!-- START SNIPPET: description -->
* <p/>
* An interceptor that handles setting the locale specified in a session as the locale for the current action request.
* In addition, this interceptor will look for a specific HTTP request parameter and set the locale to whatever value is
* provided. This means that this interceptor can be used to allow for your application to dynamically change the locale
* for the user's session or, alternatively, only for the current request (since XWork 2.1.3).
* This is very useful for applications that require multi-lingual support and want the user to
* be able to set his or her language preference at any point. The locale parameter is removed during the execution of
* this interceptor, ensuring that properties aren't set on an action (such as request_locale) that have no typical
* corresponding setter in your action.
* <p/>
* <p/>For example, using the default parameter name, a request to <b>foo.action?request_locale=en_US</b>, then the
* locale for US English is saved in the user's session and will be used for all future requests.
* <p/>
if there is no locale set (for example with the first visit), the interceptor uses the browser locale.
* <p/>
* <!-- END SNIPPET: description -->
* <p/>
* <p/> <u>Interceptor parameters:</u>
* <p/>
* <!-- START SNIPPET: parameters -->
* <p/>
* <ul>
* <p/>
* <li>parameterName (optional) - the name of the HTTP request parameter that dictates the locale to switch to and save
* in the session. By default this is <b>request_locale</b></li>
* <p/>
* <li>requestOnlyParameterName (optional) - the name of the HTTP request parameter that dictates the locale to switch to
* for the current request only, without saving it in the session. By default this is <b>request_only_locale</b></li>
* <p/>
* <li>attributeName (optional) - the name of the session key to store the selected locale. By default this is
* <b>WW_TRANS_I18N_LOCALE</b></li>
* <p/>
* </ul>
* <p/>
* <!-- END SNIPPET: parameters -->
* <p/>
* <p/> <u>Extending the interceptor:</u>
* <p/>
* <p/>
* <p/>
* <!-- START SNIPPET: extending -->
* <p/>
* There are no known extensions points for this interceptor.
* <p/>
* <!-- END SNIPPET: extending -->
* <p/>
* <p/> <u>Example code:</u>
* <p/>
* <pre>
* <!-- START SNIPPET: example -->
* <action name="someAction" class="com.examples.SomeAction">
* <interceptor-ref name="i18n"/>
* <interceptor-ref name="basicStack"/>
* <result name="success">good_result.ftl</result>
* </action>
* <!-- END SNIPPET: example -->
* </pre>
*
* @author Aleksei Gopachenko
*/
public class I18nInterceptor extends AbstractInterceptor {
private static final long serialVersionUID = 2496830135246700300L; protected static final Logger LOG = LoggerFactory.getLogger(I18nInterceptor.class); public static final String DEFAULT_SESSION_ATTRIBUTE = "WW_TRANS_I18N_LOCALE";
public static final String DEFAULT_PARAMETER = "request_locale";
public static final String DEFAULT_REQUESTONLY_PARAMETER = "request_only_locale"; protected String parameterName = DEFAULT_PARAMETER;
protected String requestOnlyParameterName = DEFAULT_REQUESTONLY_PARAMETER;
protected String attributeName = DEFAULT_SESSION_ATTRIBUTE; // Request-Only = None
protected enum Storage { SESSION, NONE } public I18nInterceptor() {
if (LOG.isDebugEnabled()) {
LOG.debug("new I18nInterceptor()");
}
} public void setParameterName(String parameterName) {
this.parameterName = parameterName;
} public void setRequestOnlyParameterName(String requestOnlyParameterName) {
this.requestOnlyParameterName = requestOnlyParameterName;
} public void setAttributeName(String attributeName) {
this.attributeName = attributeName;
} @Override
public String intercept(ActionInvocation invocation) throws Exception {
if (LOG.isDebugEnabled()) {
LOG.debug("intercept '#0/#1' {",
invocation.getProxy().getNamespace(), invocation.getProxy().getActionName());
} LocaleFinder localeFinder = new LocaleFinder(invocation);
Locale locale = getLocaleFromParam(localeFinder.getRequestedLocale());
locale = storeLocale(invocation, locale, localeFinder.getStorage());
saveLocale(invocation, locale); if (LOG.isDebugEnabled()) {
LOG.debug("before Locale=#0", invocation.getStack().findValue("locale"));
} final String result = invocation.invoke(); if (LOG.isDebugEnabled()) {
LOG.debug("after Locale=#0", invocation.getStack().findValue("locale"));
LOG.debug("intercept } ");
} return result;
} /**
* Store the locale to the chosen storage, like f. e. the session
*
* @param invocation the action invocation
* @param locale the locale to store
* @param storage the place to store this locale (like Storage.SESSSION.toString())
*/
protected Locale storeLocale(ActionInvocation invocation, Locale locale, String storage) {
//save it in session
Map<String, Object> session = invocation.getInvocationContext().getSession(); if (session != null) {
synchronized (session) {
if (locale == null) {
storage = Storage.NONE.toString();
locale = readStoredLocale(invocation, session);
} if (Storage.SESSION.toString().equals(storage)) {
session.put(attributeName, locale);
}
}
}
return locale;
} protected class LocaleFinder {
protected String storage = Storage.SESSION.toString();
protected Object requestedLocale = null; protected ActionInvocation actionInvocation = null; protected LocaleFinder(ActionInvocation invocation) {
actionInvocation = invocation;
find();
} protected void find() {
//get requested locale
Map<String, Object> params = actionInvocation.getInvocationContext().getParameters(); storage = Storage.SESSION.toString(); requestedLocale = findLocaleParameter(params, parameterName);
if (requestedLocale != null) {
return;
} requestedLocale = findLocaleParameter(params, requestOnlyParameterName);
if (requestedLocale != null) {
storage = Storage.NONE.toString();
}
} public String getStorage() {
return storage;
} public Object getRequestedLocale() {
return requestedLocale;
}
} /**
* Creates a Locale object from the request param, which might
* be already a Local or a String
*
* @param requestedLocale the parameter from the request
* @return the Locale
*/
protected Locale getLocaleFromParam(Object requestedLocale) {
Locale locale = null;
if (requestedLocale != null) {
locale = (requestedLocale instanceof Locale) ?
(Locale) requestedLocale :
LocalizedTextUtil.localeFromString(requestedLocale.toString(), null);
if (locale != null && LOG.isDebugEnabled()) {
LOG.debug("applied request locale=#0", locale);
}
} if (locale != null && !Arrays.asList(Locale.getAvailableLocales()).contains(locale)) {
locale = Locale.getDefault();
}
return locale;
} /**
* Reads the locale from the session, and if not found from the
* current invocation (=browser)
*
* @param invocation the current invocation
* @param session the current session
* @return the read locale
*/
protected Locale readStoredLocale(ActionInvocation invocation, Map<String, Object> session) {
Locale locale = this.readStoredLocalFromSession(invocation, session); if (locale != null) {
return locale;
} return this.readStoredLocalFromCurrentInvocation(invocation);
} protected Locale readStoredLocalFromSession(ActionInvocation invocation, Map<String, Object> session) {
// check session for saved locale
Object sessionLocale = session.get(attributeName);
if (sessionLocale != null && sessionLocale instanceof Locale) {
Locale locale = (Locale) sessionLocale;
if (LOG.isDebugEnabled()) {
LOG.debug("applied session locale=#0", locale);
}
return locale;
}
return null;
} protected Locale readStoredLocalFromCurrentInvocation(ActionInvocation invocation) {
// no overriding locale definition found, stay with current invocation (=browser) locale
Locale locale = invocation.getInvocationContext().getLocale();
if (locale != null && LOG.isDebugEnabled()) {
LOG.debug("applied invocation context locale=#0", locale);
}
return locale;
} protected Object findLocaleParameter(Map<String, Object> params, String parameterName) {
Object requestedLocale = params.remove(parameterName);
if (requestedLocale != null && requestedLocale.getClass().isArray()
&& ((Object[]) requestedLocale).length > 0) {
requestedLocale = ((Object[]) requestedLocale)[0]; if (LOG.isDebugEnabled()) {
LOG.debug("requested_locale=#0", requestedLocale);
}
}
return requestedLocale;
} /**
* Save the given locale to the ActionInvocation.
*
* @param invocation The ActionInvocation.
* @param locale The locale to save.
*/
protected void saveLocale(ActionInvocation invocation, Locale locale) {
invocation.getInvocationContext().setLocale(locale);
}}
