我似乎无法让我的网络应用程序写入我的 WEB-INF/EmailList.txt 我的代码是这样的
小服务程序:
package email;
import business.User;
import data.UserIO;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
*
* @author Richard Davy
*/
@WebServlet(name = "AddToEmailServlet", urlPatterns = {"/AddToEmailServlet"})
public class AddToEmailServlet extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet AddToEmailServlet</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet AddToEmailServlet at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//get parameters from the form
String firstName = request.getParameter("firstName");
String lastName = request.getParameter("lastName");
String email = request.getParameter("email");
//get relative file name
ServletContext context = getServletContext();
String path = context.getRealPath("/WEB-INF/EmailList.txt");
//add info to text file
User user = new User(firstName, lastName, email);
UserIO.add(user, path);
//send response to browser
response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
out.println(
"<!Doctype html public \"-//W3C//DTD HTML 4.0 Transitional//EN\">\n"
+ "<html>\n"
+ "<head>\n"
+ " <title>Thank you for Joining</title>\n"
+ "</head>\n"
+ "<body>\n"
+ "<h1>Thanks for joining our email list</h1>\n"
+ " <p>Here is the information you gave:</p>"
+ " <table cellspacing=\"5\" cellpadding=\"5\" border=\"1\">\n"
+ " <tr>\n"
+ " <td>First Name: </td>\n"
+ " <td>" + firstName + "</td>\n"
+ " </tr>\n"
+ " <tr>\n"
+ " <td>last Name: </td>\n"
+ " <td>" + lastName + "</td>\n"
+ " </tr>\n"
+ " <tr>\n"
+ " <td>Email: </td>\n"
+ " <td>" + email + "</td>\n"
+ " </tr>"
+ " </table>\n"
+ " <p>If you wish to add another email address click the return<br/>\n"
+ " button below. </p>"
+ " <form action=\"join_email_list.html\">\n"
+ " <input type=\"submit\" value=\"return\">\n"
+ " </form>"
+ " </body>\n"
+ " </html>\n"
);
out.flush();
out.close();
}
/**
* Handles the HTTP <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
UserIO 类:
package data;
import business.User;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
/**
*
* @author Richard Davy
*/
public class UserIO {
public static void add(User user, String filepath) throws IOException{
FileOutputStream file = new FileOutputStream(filepath, true);
String firstName = user.getFirstName();
String lastName = user.getLastName();
String email = user.getEmail();
PrintWriter writer = new PrintWriter(file);
writer.println(user.getEmail() + "|" + user.getFirstName() + "|" + user.getLastName());
//System.out.print(email + "|" + firstName + "|"
// + lastName);
}
}
我已经按照预期获得了真正的路径，但它不起作用，不知道这里发生了什么我已经尝试了所有可能的方法，但我似乎无法弄清楚发生了什么，我在 Windows 7 机器上使用 Netbeans 8 和 Tomcat 8。是否有我忽略的可能需要重新配置的东西。
最佳答案
修改 UserIO 类中的 add 方法如下:
public static void add(User user, String filepath) throws IOException {
BufferedWriter buffer;
buffer = new BufferedWriter(new FileWriter(filepath, true));
buffer.write(user.getEmail() + "|" + user.getFirstName() + "|"
+ user.getLastName());
buffer.newLine();
buffer.close();
}
关于java - 从 servlet 和 jsp 打印到 txt 文件，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24154505/