将jsp响应作为servlet中的字符串获取

有没有办法从jsp文件中获取响应作为servlet内的String。 就像是

protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String section1 = getResponseFromJSP(); // do something else ... sendMailToUser(section1); } 

我正在使用Servlet API 2.4和java 1.4

Answer 1

更好的解决方案可能是使用另一个模板引擎，如freemarker或velocity，它们独立于servlet api，更适合基于文本的电子邮件。

但是，这可以通过包装HttpServletResponse和重写getWriter方法来实现。 以下代码适用于glassfish。

Servlet的：

 public class TestServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpServletResponseWrapper responseWrapper = new HttpServletResponseWrapper(response) { private final StringWriter sw = new StringWriter(); @Override public PrintWriter getWriter() throws IOException { return new PrintWriter(sw); } @Override public String toString() { return sw.toString(); } }; request.getRequestDispatcher("test.jsp").include(request, responseWrapper); String content = responseWrapper.toString(); System.out.println("Output : " + content); response.getWriter().write(content); } } 

JSP：

 <%@page contentType="text/html" pageEncoding="UTF-8"%>        
<%= "Hello world from a JSP!" %>