Java Web服務中的NoSuchMethodException

Question

我創建了一個需要添加人員，檢索所有人員以及檢索單個工作人員的java web服務。除了增加員工之外，一切都在工作。我得到一個NoSuchMethodException。我現在已經完成了100次代碼，似乎沒有任何改變。

首先，我有一個文本字段一個jsp頁面中添加一個工作人員：

<fieldset> 
     <form action="#"> 
      <legend>Add Staff Members</legend> 
      <label>First name: <input type="text" id="forename" /> </label> 
      <br /> 
      <label>Last name: <input type="text" id="surname" /></label> 
      <br /> 
      <label>Email: <input type="text" id="email" /></label> 
      <br /> 
      <label>Phone Number: <input type="text" id="phone_num" /></label> 
      <br /> 
      <label>Address: <input type="text" id="address" /></label> 
      <br /> 
      <input type="button" value="Add Staff" 
       onclick='addStaffMember("forename", "surname", "email", "phone_num", "address", "staff_result_add")' /> 
     </form> 
     <div id="staff_result_add"></div> 
    </fieldset> 

當用戶點擊該按鈕，一個JavaScript函數的調用。 JS的功能如下：

function addStaffMember(firstname, lastname, address, phone_num, email, resultRegion) { 
var web_xml_address = "add-staff-member"; 
var data = "&firstname=" 
     + getValue(firstname) + "&lastname=" + getValue(lastname) + "&address=" + getValue(address) 
     + "&phone_num=" + getValue(phone_num) + "&email=" + getValue(email); 
var address = web_xml_address + "?" + data; 
ajaxResult(address, resultRegion); 

}

這則轉到我的web.xml文件中找到相關的java類：

<servlet> 
    <servlet-name>Add Staff Servlet</servlet-name> 
    <servlet-class>com.coreservlets.AddStaffMember</servlet-class> 
</servlet> 
<servlet-mapping> 
    <servlet-name>Add Staff Servlet</servlet-name> 
    <url-pattern>/add-staff-member</url-pattern> 
</servlet-mapping> 

這後來終於進入到我的Java方法：

package com.coreservlets; 

import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.SQLException; 



public class AddStaffMember { 

public Connection connection; 

public AddStaffMember(String dbName, String username, String password)  { 
    String url = "jdbc:mysql://mudfoot.doc.stu.mmu.ac.uk:3306/" + dbName; 

    try { 
     Class.forName("com.mysql.jdbc.Driver").newInstance(); 
     System.out.println("Connected"); 
     connection = DriverManager.getConnection(url, username, password); 
    } catch (InstantiationException | IllegalAccessException 
      | ClassNotFoundException | SQLException e) { 
     e.printStackTrace(); 
     System.out.println("Disconnected"); 
    } 
} 

public void addStaffMember(StaffInfo staff) throws SQLException { 
    String query = "insert into staff_info (staff_id, forename, surname, address, phone_number, email) values (?,?,?,?,?,?)"; 
    try { 
     PreparedStatement statement =   connection.prepareStatement(query); 
     statement.setInt(1, staff.getStaffID()); 
     statement.setString(2, staff.getForename()); 
     statement.setString(3, staff.getSurname()); 
     statement.setString(4, staff.getLocation()); 
     statement.setString(5, staff.getPhone()); 
     statement.setString(6, staff.getEmail());   
     statement.executeUpdate(); 
    } catch (SQLException e) { 
     e.printStackTrace(); 
    } 
} 

} 

它然後由servlet調用執行：

package com.dunn.servlets; 

import java.io.IOException; 
import java.sql.SQLException; 

import javax.servlet.RequestDispatcher; 
import javax.servlet.ServletException; 
import javax.servlet.annotation.WebServlet; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 

import com.coreservlets.AddStaffMember; 
import com.coreservlets.StaffInfo; 

/** 
* Servlet implementation class AddStaffMemberServlet 
*/ 
@WebServlet("/AddStaffMemberServlet") 
public class AddStaffMemberServlet extends HttpServlet { 
private static final long serialVersionUID = 1L; 

/** 
* @see HttpServlet#HttpServlet() 
*/ 
public AddStaffMemberServlet() { 
    super(); 
} 

/** 
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse 
*  response) 
*/ 
public void doGet(HttpServletRequest request, 
     HttpServletResponse response) throws ServletException, IOException { 
    doPost(request, response); 
} 

/** 
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse 
*  response) 
*/ 
public void doPost(HttpServletRequest request, 
     HttpServletResponse response) throws ServletException, IOException { 
    String forename = request.getParameter("forename"); 
    String surname = request.getParameter("surname"); 
    String address = request.getParameter("address"); 
    String email = request.getParameter("email"); 
    String phone = request.getParameter("phone"); 

    StaffInfo staffMember = new StaffInfo(); 

    //staffMember.setStaffID(100); 
    staffMember.setForename(forename); 
    staffMember.setSurname(surname); 
    staffMember.setLocation(address); 
    staffMember.setPhone(phone); 
    staffMember.setEmail(email); 

    AddStaffMember addStaffMember = new AddStaffMember("staff_info", "dunnj", "grustpOl8"); 
    try { 
     addStaffMember.addStaffMember(staffMember); 
     System.out.println(" Member added "); 
    } catch (SQLException e) { 
     e.printStackTrace(); 
     System.out.println(" Errorr "); 

    } 


} 

} 

我不知道怎麼回事，找不到任何相關的在線!!!

一些幫助將不勝感激！

我得到的錯誤是：

Answer 1

你的類AddStaffMember需要一個無參數的構造函數。