很多人在找，在一個普通類裡如何才能取系統的request或session,我也找了下，但沒有，就自己實現了一下，期待需要的有緣人，希望能幫到一點點。

具體如下：

實現步驟：

1.定義一個執行緒類，普通的：

類裡最主要的就是定義了一個引數：

private static ThreadLocal<HttpServletRequest> httpRequest = new ThreadLocal<HttpServletRequest>();

另外給了set  get  remove和執行緒相關的三個方法；

具體如下：

public class SystemRequestContext {
	
	private static ThreadLocal<HttpServletRequest> httpRequest = new ThreadLocal<HttpServletRequest>();
	private static ThreadLocal<HttpSession> session = new ThreadLocal<HttpSession>();
	
	public static void removeHttpSession()
	{
		session.remove();
	}
	
	public static HttpSession getSession() {
		return session.get();
	}

	public static void setSession(HttpSession _session) {
		session.set(_session);
	}
 

2.定義一個filter,攔截所有的請求，把request裝入

SystemRequestContext 

public void doFilter(ServletRequest req, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest)req;
		SystemRequestContext.setHttpRequest(request);
		SystemRequestContext.setSession(request.getSession());
		try{
			chain.doFilter(request, response);
		}finally{
			SystemRequestContext.removeHttpRequest();
			SystemRequestContext.removeHttpSession();
		}
	}
 

public class UserModuleValidateTag {
	
	public static boolean validateModule(String module)
	{
		HttpServletRequest request = SystemRequestContext.getHttpRequest();
		if(null!=request)
			System.out.println("^_^"+request);