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Servlet отказывается от моего iD (не может преобразовать String в INT, но это INT), чтобы работать, это int от http://puu.sh/cGvGN/6d29084aec.png (это поддельные для школьного lol)Подключение сервлетов (INT к STRING) ИЛИ (строка в Int)
Как я могу заставить это работать? Я думал, что сделал это правильно, но Servlet перестает работать
Что происходит, так это то, что страница не загружается на страницу ViewStudentSchedule, потому что id INT не работает. (Это дает мне BLANK PAGE)
Проблемы:
- ли ID Int?
- Если это так, то как я могу подключить его к сервлету, струны работали нормально, но работа с INTS теперь становится неприятной.
- На картинке, показывающей базу данных, все прямо в базе данных, чтобы вытащить информацию ?
Заранее благодарен.
Вот Servlet
@WebServlet(urlPatterns = {"/StudentLoginServlet"})
public class StudentLoginServlet 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. */
int iD = Integer.parseInt("iD");
iD = request.getParameter("iD");
System.out.println(iD);
String pw = request.getParameter("pw");
System.out.println(pw);
Student s1=new Student();
s1.findDB(iD);
String fn=s1.getFirstName();
System.out.println(fn);
String ln=s1.getLastName();
System.out.println(ln);
String pwdb=s1.getPassword();
System.out.println(pwdb);
RequestDispatcher rd;
HttpSession ses1=request.getSession();
ses1.setAttribute("s1", s1);
if (pw.equals(pwdb)){
rd= request.getRequestDispatcher("/ViewStudentSchedule.jsp");
rd.forward(request,response);
System.out.println("works");
}
else{
rd= request.getRequestDispatcher("/LoginError.jsp");
rd.forward(request,response);
System.out.println("no works");
}
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* 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 {
processRequest(request, response);
}
/**
* 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 {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
А вот в бизнес-объект
public class Student implements Serializable {
private int iD;
private String password;
private String firstName;
private String lastName;
private String street;
private String city;
private String state;
private double zip;
private String eMail;
private double gpa;
private String message;
/**
* No arg constructor that sets the default value of all
* customer properties to an empty string value.
*/
public Student() {
this.iD = 0;
this.password = "";
this.firstName = "";
this.lastName = "";
this.street = "";
this.city = "";
this.state = "";
this.zip = 0;
this.eMail = "";
this.gpa = 0;
}
public void setID(int id) {
this.iD = iD;
}
public void setPassword(String password) {
this.password = password;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public void SetLastName(String lastName) {
this.lastName = lastName;
}
public void setStreet(String street) {
this.street = street;
}
public void setCity(String city) {
this.city = city;
}
public void setState(String state) {
this.state = state;
}
public void setZip(double zip) {
this.zip = zip;
}
public void setEMail (String email) {
this.eMail = email;
}
public void setGpa(double gpa) {
this.gpa = gpa;
}
public int getID() {
return iD;
}
public String getPassword() {
return password;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
public String getStreet() {
return street;
}
public String getCity() {
return city;
}
public String getState() {
return state;
}
public double getZip() {
return zip;
}
public String getEMail() {
return eMail;
}
public double getGpa() {
return gpa;
}
public String getMessage() {
return this.message;
}
public boolean login(String password) throws SQLException {
boolean yes_no = false;
/* Verify password against database password for the userId */
if (password.equals(this.password)) {
this.message = "Thank you, you are logged in.";
yes_no = true;
} else {
this.message = "Sorry Your Login Information seems to be incorrect.";
yes_no = false;
}
/* Returns true or false based on the condition statement above */
return yes_no;
}
/**
* Establishes connection with the database containing the customer information
* @return Connection
*/
public Connection studentConnect() {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
} catch (ClassNotFoundException e) {
System.out.println("Errors: " + e);
}
Connection connect = null;
try {
connect = DriverManager.getConnection("jdbc:odbc:RegisDB");
} catch (SQLException e) {
System.out.println("You have Errors: " + e);
}
return connect;
}
/**
* Takes the student Id and retrieves the information from the customers
* data table and stores it in the properties of the customer object.
* @param iD
* @throws SQLException
*/
public void findDB(int iD) {
Connection con = studentConnect();
Statement statement = null;
ResultSet result = null;
String sql = "Select * From Students Where iD = " + iD + ";";
try {
statement = con.createStatement();
result = statement.executeQuery(sql);
while (result.next()) {
this.iD = result.getInt("iD");
this.password = result.getString("password");
this.firstName = result.getString("firstName");
this.lastName = result.getString("lastName");
this.street = result.getString("street");
this.city = result.getString("city");
this.state = result.getString("state");
this.zip = result.getDouble("zip");
this.eMail = result.getString("eMail");
this.gpa = result.getDouble("gpa");
}
con.close();
} catch (SQLException e) {
System.out.println("Errors: " + e);
}
}
/**
* Takes in the parameters of the customer database and inserts the parameters taken into
* the database for the addition of customers to the database.
* @param password
* @param firstName
* @param lastName
* @param street
* @param city
* @param state
* @param zip
* @param email
* @param gpa
* @throws SQLException
*/
public void insertDB(String password, String firstName, String lastName, String street, String city, String state, double zip, String email, double gpa) throws SQLException {
Connection con = studentConnect();
Statement statement;
ResultSet result;
int resultVal;
String sql = "INSERT INTO Students (password, firstName, lastName, street, city, state, zip, eMail, gpa) VALUES ('" + password + "','" + firstName + "','" + lastName + "','" + street + "','" + city +"','" + state +"','" + zip + "','" + eMail +"','" + gpa + "');";
try {
statement = con.createStatement();
resultVal = statement.executeUpdate(sql);
System.out.println(resultVal);
} catch (SQLException e) {
System.out.println("Error: " + e);
System.out.println(e.getStackTrace());
} finally {
con.close();
}
}
/**
* Takes in student id and locates the customer in the database, performs
* an sql update and deletes the customer from the database.
* @param iD
* @throws SQLException
*/
public void deleteDB(int iD) throws SQLException {
Connection con = studentConnect();
Statement statement;
int resultVal;
String sql = "DELETE FROM Students WHERE iD = " + iD + "';";
try {
statement = con.createStatement();
resultVal = statement.executeUpdate(sql);
System.out.println(resultVal);
} catch (SQLException e) {
System.out.println("Errors: " + e);
} finally {
con.close();
}
}
}
Вы объявили 'Int iD'. Как ты думаешь, что это? Что возвращает 'request.getParameter (« iD »)? –