1）、编写国际化配置文件；
2）、使用ResourceBundleMessageSource管理国际化资源文件
3）、在页面使用fmt:message取出国际化内容
步骤：
1）、编写国际化配置文件，抽取页面需要显示的国际化消息
国际化文件是peroperties文件
自动识别国际化视图
通过国际化视图创建国际化配置文件
同时对比编辑多个配置文件
配置国际化文件路径：
spring.messages.basename=static.i18n.login
@Configuration
@ConditionalOnMissingBean(
value = {MessageSource.class},
search = SearchStrategy.CURRENT
)
@AutoConfigureOrder(-2147483648)
@Conditional({MessageSourceAutoConfiguration.ResourceBundleCondition.class})
@EnableConfigurationProperties
public class MessageSourceAutoConfiguration {
private static final Resource[] NO_RESOURCES = new Resource[0]; public MessageSourceAutoConfiguration() {
} @Bean
@ConfigurationProperties(
prefix = "spring.messages"
)
public MessageSourceProperties messageSourceProperties() {
return new MessageSourceProperties();
} @Bean
public MessageSource messageSource(MessageSourceProperties properties) {
ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
if (StringUtils.hasText(properties.getBasename())) {
//设置国际化文件的基础名称（去掉语言_国家代{zh_CN}）的）:即默认是message.properties,上图中我们起的名称是login.properties
messageSource.setBasenames(StringUtils.commaDelimitedListToStringArray(StringUtils.trimAllWhitespace(properties.getBasename())));
} if (properties.getEncoding() != null) {
messageSource.setDefaultEncoding(properties.getEncoding().name());
} messageSource.setFallbackToSystemLocale(properties.isFallbackToSystemLocale());
Duration cacheDuration = properties.getCacheDuration();
if (cacheDuration != null) {
messageSource.setCacheMillis(cacheDuration.toMillis());
} messageSource.setAlwaysUseMessageFormat(properties.isAlwaysUseMessageFormat());
messageSource.setUseCodeAsDefaultMessage(properties.isUseCodeAsDefaultMessage());
return messageSource;
} protected static class ResourceBundleCondition extends SpringBootCondition {
private static ConcurrentReferenceHashMap<String, ConditionOutcome> cache = new ConcurrentReferenceHashMap(); protected ResourceBundleCondition() {
} public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
//自定义的话就用此属性：spring.messages.basename来指定，默认叫message.propertie
//我们上图的需要指定为：spring.messages.basename=login
String basename = context.getEnvironment().getProperty("spring.messages.basename", "messages");
ConditionOutcome outcome = (ConditionOutcome)cache.get(basename);
if (outcome == null) {
outcome = this.getMatchOutcomeForBasename(context, basename);
cache.put(basename, outcome);
} return outcome;
} private ConditionOutcome getMatchOutcomeForBasename(ConditionContext context, String basename) {
Builder message = ConditionMessage.forCondition("ResourceBundle", new Object[0]);
String[] var4 = StringUtils.commaDelimitedListToStringArray(StringUtils.trimAllWhitespace(basename));
int var5 = var4.length; for(int var6 = 0; var6 < var5; ++var6) {
String name = var4[var6];
Resource[] var8 = this.getResources(context.getClassLoader(), name);//类路径
int var9 = var8.length; for(int var10 = 0; var10 < var9; ++var10) {
Resource resource = var8[var10];
if (resource.exists()) {
return ConditionOutcome.match(message.found("bundle").items(new Object[]{resource}));
}
}
} return ConditionOutcome.noMatch(message.didNotFind("bundle with basename " + basename).atAll());
} private Resource[] getResources(ClassLoader classLoader, String name) {
String target = name.replace('.', '/'); try {
//类路径下的 message.properties 和 messages_zh_CN.properties 或 自己指定的xxxx.properties 、xxxx.preperties
return (new PathMatchingResourcePatternResolver(classLoader)).getResources("classpath*:" + target + ".properties");
} catch (Exception var5) {
return MessageSourceAutoConfiguration.NO_RESOURCES;
}
}
}
}
public class MessageSourceProperties {
private String basename = "messages";//我们的配置文件可以直接放在类路径下，默认名称叫message.properties
private Charset encoding;
@DurationUnit(ChronoUnit.SECONDS)
private Duration cacheDuration;
private boolean fallbackToSystemLocale;
private boolean alwaysUseMessageFormat;
private boolean useCodeAsDefaultMessage;
public MessageSourceProperties() {
this.encoding = StandardCharsets.UTF_8;
this.fallbackToSystemLocale = true;
this.alwaysUseMessageFormat = false;
this.useCodeAsDefaultMessage = false;
}
public String getBasename() {
return this.basename;
}
public void setBasename(String basename) {
this.basename = basename;
}
......
}
<!-- 中英文切换链接 -->
<a class="btn btn-sm" th:href="@{/index.html(l='zh_CN'}">中文</a>
<a class="btn btn-sm" th:href="@{/index.html(l='en_US')}">English</a>
是根据浏览器的默认语言识别的
不过取出来的中文有乱码
IDEA中将UTF-8自动组转为ASSIC码
File ——》 settings 里的设置只是针对当前项目的设置，要想设置全局的
Settins ——》Other Settings ——》Default Settings 设置全局的默认设置
然后重新编辑有乱码的properties文件
根据浏览器的默认语言设置自动区分国际化字段的显示
默认请求头里会有语言的信息
切换默认的语言，请求头中排在第一位的也就变了
实现原理：
国际化Locale（区域信息对象）；LocaleResolver（获取区域信息对象）
public class WebMvcAutoConfiguration {
public static class WebMvcAutoConfigurationAdapter implements WebMvcConfigurer, ResourceLoaderAware {
@Bean
@ConditionalOnMissingBean //当项目中没有区域解析器的时候，才执行这个SprigBoot默认的配置，所以可以自定义
@ConditionalOnProperty(
prefix = "spring.mvc",
name = {"locale"}
)
//
public LocaleResolver localeResolver() {
//默认从配置文件中获取
if (this.mvcProperties.getLocaleResolver() == org.springframework.boot.autoconfigure.web.servlet.WebMvcProperties.LocaleResolver.FIXED) {
return new FixedLocaleResolver(this.mvcProperties.getLocale());
} else {//如果配置文件中没有，则从HttpRequest的header中获取
AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver();
localeResolver.setDefaultLocale(this.mvcProperties.getLocale());
return localeResolver;
}
}
}
public class AcceptHeaderLocaleResolver implements LocaleResolver {
public Locale resolveLocale(HttpServletRequest request) {
Locale defaultLocale = this.getDefaultLocale();
if (defaultLocale != null && request.getHeader("Accept-Language") == null) {
return defaultLocale;
} else {
Locale requestLocale = request.getLocale();
List<Locale> supportedLocales = this.getSupportedLocales();
if (!supportedLocales.isEmpty() && !supportedLocales.contains(requestLocale)) {
Locale supportedLocale = this.findSupportedLocale(request, supportedLocales);
if (supportedLocale != null) {
return supportedLocale;
} else {//如果默认的区域解析器为空，则从requset请求头中获取
return defaultLocale != null ? defaultLocale : requestLocale;
}
} else {
return requestLocale;
}
}
}
}
自定义区域解析器，点击链接切换国际化
public class MyLocaleResolver implements LocaleResolver {
@Override
public Locale resolveLocale(HttpServletRequest request) {
String l = request.getParameter("l");
Locale locale = Locale.getDefault();
if (!StringUtils.isEmpty(l)) {
String[] split = l.split("_");
locale = new Locale(split[0], split[1]);
}
return locale;
}
@Override
public void setLocale(HttpServletRequest httpServletRequest, @Nullable HttpServletResponse httpServletResponse, @Nullable Locale locale) {
}
}
//将自定义的区域解析器加入到容器中来
@Bean
public LocaleResolver localeResolver(){
return new MyLocaleResolver();
}