我是servlets和所有这个主题的新手，如果它有点乱，那就很抱歉！我正在尝试从servlet向javascript发送一个值或在java脚本中获取servlet方法的值。我不确定doGet！我做得对吗？获取字段的值并将结果发送到javascript？
Servlet的：
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try {
String passengerCount = request.getParameter("passengerCount");
String departureSchedule = request.getParameter("schedule");
String arrivalSchedule = request.getParameter("returnschedule");
HttpSession session = request.getSession(true);
int departureSID = 0;
int passengerCountInt = 0;
userID = 0;
int arrivalSID = 0;
try {
departureSID = Integer.parseInt(departureSchedule);
passengerCountInt = Integer.parseInt(passengerCount);
userID = Integer.parseInt(session.getAttribute("userID").toString());
arrivalSID = Integer.parseInt(arrivalSchedule);
} catch (Exception e) {
}
if (departureSID != 0) {
ScheduleBean departureSb = new ScheduleBean();
departureSb.selectSchedule(departureSID);
int departureRoute = departureSb.getRouteID();
RouteBean routeB1 = new RouteBean();
routeB1.selectRoute(departureRoute);
double routeCharge = routeB1.getCharge();
double totalDCharge = routeCharge * passengerCountInt;
ReservationBean rb = new ReservationBean();
UserBean us = new UserBean();
if (arrivalSchedule == null) {
rb.saveOneWayReservation(departureSID, userID, totalDCharge, passengerCountInt, "TICKET");
} else {
departureSb.selectSchedule(arrivalSID);
int arrivalRoute = departureSb.getRouteID();
routeB1.selectRoute(arrivalRoute);
double arrivalRouteCharge = routeB1.getCharge();
totalDCharge += arrivalRouteCharge * passengerCountInt;
rb.saveRoundReservation(departureSID, arrivalSID, userID, totalDCharge, passengerCountInt, "TICKET");
}
ScheduleBean sbb = new ScheduleBean();
sbb.selectSchedule(rb.scheduleID);
AirBean bbb = new AirBean();
bbb.selectAir(sbb.getAirID());
String AirCode = bbb.getAirCode();
String username = session.getAttribute("username").toString();
int referenceNumber = rb.reservationID + 100;
rb.updateTicketNumber(AirCode + "-" + username + "-" + String.valueOf(referenceNumber));
out.println("<html>");
out.println("<head>");
out.println("<title>Make payment</title>");
out.println("<script type='text/javascript' src='js/jquery-1.5.2.min.js'></script>");
out.println("<script type='text/javascript' src='js/payment.js'></script>");
out.println("<script src='http://code.jquery.com/jquery-latest.min.js'></script>");
out.println("<link type='text/css' href='css/style.css' rel='Stylesheet' />");
out.println("</head>");
out.println("<body>");
out.println("<div class='bg-light' style='width: 200px; height: 200px; position: absolute; left:50%; top:50%; margin:-100px 0 0 -100px; padding-top: 40px; padding-left: 10px;'>");
out.println("<input id='reservationID' style='display: none' value='" + rb.reservationID + "' />");
out.println("<div>Credit Card Number : </div>");
out.println("<div><input id='creditcard' onKeyPress='return checkIt(event);' type='text' name='creditcard' maxlength='16' /></div>");
out.println("<div>ExpirationDate : </div>");
out.println("<div><input id='expirationDate' type='text' onKeyPress='return checkIt(event);' name='expirationDate' maxlength='4' /></div>");
out.println("<input type='hidden' id='FormName' name='FormName' value='" + HiddenValue + "'>");
out.println("<div><input id='somebutton' type='button' name='buttonsave' value='Make Payment' onclick='makePayment(" + rb.reservationID + ");' /></div>");
out.println("<div><input type='button' name='buttoncancel' value='Cancel Payment' onclick='cancelPayment(" + rb.reservationID + ");' /></div>");
out.println("</div>");
out.println("</body>");
out.println("</html>");
}
} finally {
out.close();
}
}
我正在尝试获取两个输入字段的值进程并将结果发送到javascript
Servlet doGet：
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
creditno = request.getParameter("creditcard"); //name of the input field, not id
expiration = request.getParameter("expirationDate"); //name of the input field should be expirationDate
UserBean us = new UserBean();
boolean check = us.checkCC(userID, creditno, expiration); // process the fields
if (check == true) {
CCA = "1";
} else {
CCA = "0";
}
response.setContentType("text/plain"); // Set content type of the response so that jQuery knows what it can expect.
response.setCharacterEncoding("UTF-8"); // You want world domination, huh?
response.getWriter().write(CCA); // Write response body.
}
Servlet doPost：
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
使用Javascript：
var tempresp;
$(document).ready(function() { // When the HTML DOM is ready loading, then execute the following function...
$('#somebutton').click(function() { // Locate HTML DOM element with ID "somebutton" and assign the following function to its "click" event...
$.get('MakeReservation', function(responseText) { // Execute Ajax GET request on URL of "someservlet" and execute the following function with Ajax response text...
alert(responseText);
tempresp=responseText;
});
});
});
提前致谢！
你有你的java权限，它是request.getParameter（...）。但是你不使用javascript发送任何数据。如果您要发送“GET”请求，请使用您拥有的代码，但进行以下更改：
$.get('MakeReservation?creditcard=12345&expirationDate=11%2F14', ....);
我会查看一些关于使用get和post方法的JQuery教程。此外，您可能想要注释掉您拥有的代码，并且只是测试一些变量的发送，以便在您深入了解Java方面之前了解事情。
您没有向Servlet发送任何参数。即使你这样做，你也会遇到IllegalStateException。这是因为您正在使用out.println()写入响应正文，然后设置标题。该声明
finally {
out.close();
}
还会刷新输出流，阻止您编写任何响应标头。
在写入响应主体之前设置任何标头，并在$.get中传递所需的参数
$.get('MakeReservation', {passengerCount: 2, arrivalSchedule: 123}, function(responseText) { // Execute Ajax GET request on URL of "someservlet" and execute the following function with Ajax response text...
alert(responseText);
});