Java ServletRequest.getRequestDispatcher方法代码示例

import javax.servlet.ServletRequest; //导入方法依赖的package包/类
/**
 * Perform a RequestDispatcher.include() operation, with optional flushing
 * of the response beforehand.
 *
 * @param request The servlet request we are processing
 * @param response The servlet response we are processing
 * @param relativePath The relative path of the resource to be included
 * @param out The Writer to whom we are currently writing
 * @param flush Should we flush before the include is processed?
 *
 * @exception IOException if thrown by the included servlet
 * @exception ServletException if thrown by the included servlet
 */
public static void include(ServletRequest request,
                           ServletResponse response,
                           String relativePath,
                           JspWriter out,
                           boolean flush)
    throws IOException, ServletException {

    if (flush && !(out instanceof BodyContent))
        out.flush();

    // FIXME - It is tempting to use request.getRequestDispatcher() to
    // resolve a relative path directly, but Catalina currently does not
    // take into account whether the caller is inside a RequestDispatcher
    // include or not.  Whether Catalina *should* take that into account
    // is a spec issue currently under review.  In the mean time,
    // replicate Jasper's previous behavior

    String resourcePath = getContextRelativePath(request, relativePath);
    RequestDispatcher rd = request.getRequestDispatcher(resourcePath);

    rd.include(request,
               new ServletResponseWrapperInclude(response, out));

}
 

import javax.servlet.ServletRequest; //导入方法依赖的package包/类
@Override
public void doFilter(ServletRequest reg, ServletResponse res, FilterChain chain) throws IOException,
        ServletException {
    RequestDispatcher reqDispatcher = reg.getRequestDispatcher("deny.html");
    String remoteIP = reg.getRemoteAddr();// 获取访问服务器的IP
    String[] ips = null;
    boolean isAllow = false;
    Pattern pattern = null;
    if (!StringUtils.isEmpty(notFilteredIPs)) {
        ips = notFilteredIPs.split(";");
        for (String ip : ips) {
            pattern = Pattern.compile(ip);
            if (pattern.matcher(remoteIP).find()) {
                isAllow = true;
                break;
            }
        }
    } else {
        isAllow = true;
    }
    if (isAllow) {
        // 如果不是要过滤的IP就放行，交给下一个Filter
        chain.doFilter(reg, res);
    } else {
        logger.error("访问服务器的IP:" + remoteIP + " , 该IP地址无法访问");
        // 如果是要过滤的IP，就通过reqDispatcher跳转到错误页面。
        reqDispatcher.forward(reg, res);
    }
}
 

import javax.servlet.ServletRequest; //导入方法依赖的package包/类
/**
 * Perform a RequestDispatcher.include() operation, with optional flushing
 * of the response beforehand.
 *
 * @param request
 *            The servlet request we are processing
 * @param response
 *            The servlet response we are processing
 * @param relativePath
 *            The relative path of the resource to be included
 * @param out
 *            The Writer to whom we are currently writing
 * @param flush
 *            Should we flush before the include is processed?
 *
 * @exception IOException
 *                if thrown by the included servlet
 * @exception ServletException
 *                if thrown by the included servlet
 */
public static void include(ServletRequest request, ServletResponse response, String relativePath, JspWriter out,
		boolean flush) throws IOException, ServletException {

	if (flush && !(out instanceof BodyContent))
		out.flush();

	// FIXME - It is tempting to use request.getRequestDispatcher() to
	// resolve a relative path directly, but Catalina currently does not
	// take into account whether the caller is inside a RequestDispatcher
	// include or not. Whether Catalina *should* take that into account
	// is a spec issue currently under review. In the mean time,
	// replicate Jasper's previous behavior

	String resourcePath = getContextRelativePath(request, relativePath);
	RequestDispatcher rd = request.getRequestDispatcher(resourcePath);

	rd.include(request, new ServletResponseWrapperInclude(response, out));

}