在SpringMVC的源代码中也提供了一个封装过的ThreadLocal,其中保存了每次请求的HttpServletRequest对象,(详细请看org.springframework.web.context.request.ServletRequestAttributes的源代码) 。
这样我们就可以进行简单封装一下写一个工具进行使用:
*当然必不可少的一点一定记得,在web.xml里必须要有相应的配置来支持
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
工具类代码:
package samples.utils;
import java.util.Arrays;
import java.util.Collection;
import java.util.Locale;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.MessageSource;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.ui.context.Theme;
import org.springframework.util.ClassUtils;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.ThemeResolver;
import org.springframework.web.servlet.support.RequestContextUtils;
/**
* SpringMVC通用工具
* @author
*/
public final class WebContextHolder {
private static final Logger LOGGER = LoggerFactory.getLogger(WebContextHolder.class);
private static final WebContextHolder INSTANCE = new WebContextHolder();
public WebContextHolder get() {
return INSTANCE;
}
private WebContextHolder() {
super();
}
// --------------------------------------------------------------------------------------------------------------
public HttpServletRequest getRequest() {
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
return attributes.getRequest();
}
public HttpSession getSession() {
return getSession(true);
}
public HttpSession getSession(boolean create) {
return getRequest().getSession(create);
}
public String getSessionId() {
return getSession().getId();
}
public ServletContext getServletContext() {
return getSession().getServletContext(); // servlet2.3
}
public Locale getLocale() {
return RequestContextUtils.getLocale(getRequest());
}
public Theme getTheme() {
return RequestContextUtils.getTheme(getRequest());
}
public ApplicationContext getApplicationContext() {
return WebApplicationContextUtils.getWebApplicationContext(getServletContext());
}
public ApplicationEventPublisher getApplicationEventPublisher() {
return (ApplicationEventPublisher) getApplicationContext();
}
public LocaleResolver getLocaleResolver() {
return RequestContextUtils.getLocaleResolver(getRequest());
}
public ThemeResolver getThemeResolver() {
return RequestContextUtils.getThemeResolver(getRequest());
}
public ResourceLoader getResourceLoader() {
return (ResourceLoader) getApplicationContext();
}
public ResourcePatternResolver getResourcePatternResolver() {
return (ResourcePatternResolver) getApplicationContext();
}
public MessageSource getMessageSource() {
return (MessageSource) getApplicationContext();
}
public ConversionService getConversionService() {
return getBeanFromApplicationContext(ConversionService.class);
}
public DataSource getDataSource() {
return getBeanFromApplicationContext(DataSource.class);
}
public Collection<String> getActiveProfiles() {
return Arrays.asList(getApplicationContext().getEnvironment().getActiveProfiles());
}
public ClassLoader getBeanClassLoader() {
return ClassUtils.getDefaultClassLoader();
}
private <T> T getBeanFromApplicationContext(Class<T> requiredType) {
try {
return getApplicationContext().getBean(requiredType);
} catch (NoUniqueBeanDefinitionException e) {
LOGGER.error(e.getMessage(), e);
throw e;
} catch (NoSuchBeanDefinitionException e) {
LOGGER.warn(e.getMessage());
return null;
}
}
}