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How to pass data to from view to controller in Spring-MVC?

I have a list of objects as JSON which is inside a workLists. I created a table by iterating using each on workLists and create a table in thymeleaf?
Now how can I pass work that is a single object back to the controller, what I tried is using th:object
I thought it would work but on the controller end null values are coming.
Thymeleaf section
<tr th:each="work , status : ${workLists}">
<td scope="row" th:text="${status.count}"></td>
<td>
<form th:action="#{/edit/work}" th:object="${work}" method="post">
<button type="submit" class="dropdown-item">Edit</button>
</form>
</td>
</tr>
Controller Section
#PostMapping("/edit/work")
public String editWork(#ModelAttribute("work") GetWorkkDto getWorkDto){
logger.debug(" Inside of edit work method");
return "listOfwork";
}

You need to give the contoller 2 attribues which are the workLists and a work. It will be something like:
#GetMapping("/edit/work")
public String editWork(Model model){
model.addAttribute("workLists", workLists);
model.addAttribute("workDTO", new Work());
return "listOfwork";
}
Then in your HTML page through hidden fields you give the values of the work selected:
<table>
<tr th:each="work, stat : ${workLists}">
<td>
<form action="#" th:action="#{/edit/work}" th:object="${workDTO}" method="post">
<input type="hidden" th:attr="name='id'" th:value="${work.id}" />
<input type="hidden" th:attr="name='name'" th:value="${work.name}" />
<input type="hidden" th:attr="name='description'" th:value="${work.description}" />
<p th:text="'Id : '+${work.id}"></p>
<p th:text="'Name : '+${work.name}"></p>
<p th:text="'Description : '+${work.description}"></p>
<p><input type="submit" value="Submit" /> <input type="reset" value="Reset" /></p>
</form>
</td>
</tr>
</table>
You can see in the proposed code that I give the value of work.id to the workDTO.id through the name attribute (don't ask me why it is like this)
Finaly you retrieve the object in your controller (as you do already) with something like this:
#PostMapping("/edit/work")
public String editWork(#ModelAttribute Work workDTO, Model model){
System.out.println(workDTO.toString());
model.addAttribute("workLists", workLists);
model.addAttribute("workDTO", new Work());
return "listOfwork";
}

why is my form not passing information in spring boot

Hello i am passing information in a form and everything runs fine but when i fill out the form it doesnt not pass the information and i am getting this error.
There was an unexpected error (type=Internal Server Error, status=500).
Caused by: org.hibernate.exception.ConstraintViolationException: could not execute statement
Caused by: java.sql.SQLIntegrityConstraintViolationException: Column 'movie_id' cannot be null
the code i am using is as folow:
#PostMapping("/save")
public String save(Movie movie) {
savedMovie.save(movie);
return "redirect:/LatestMovies";
}
And
<form th:action="#{/save}" method="post" >
<p><input type="text" id="movie_id" name="movie_id" value="" /></p>
<p><input type="text" id="movie_name" name="movie_name" value="" /></p>
<p><input type="submit" value="save" /></p>
</form>
i belive all other code is correct becuase if i try to render the db information i have no problem.
Update
This is the complete html code.
<div class="container">
<table class="table table-hover">
<tr>
<th>Id</th>
<th>Name</th>
</tr>
<tr th:each="LatestMovies : ${latestMovies}">
<td th:text="${LatestMovies.id}"></td>
<td th:text="${LatestMovies.movieName}"></td>
<td>
<form th:action="#{/save}" method="post" th:object="${newMovie}">
<p><input type="text" id="movie_id" th:field="*{movie_Id}"/></p>
<p><input type="text" id="movie_name" th:field="*{movie_Name}"/></p>
<p><input type="submit" value="save" /></p>
</form>
</td>
</tr>
</table>

Your controller is expecting a Movie object, but it is receiving something else, which then produces a null Movie object. You need to use th:object in your form in order to correctly send the respective class. First, let's add a new #ModelAttribute to your controller, so that your form can automatically map your Movie object in your form.
Controller
// In order to use th:object in a form, we must be able to map a new entity to that form.
// In this case we return a Movie entity.
#ModelAttribute(value = "newMovie")
public Movie newMovie() {return new Movie();}
Now, let's change your form, so that it actually sends a Movie object.
<form th:action="#{/save}" method="post" th:object="${newMovie}">
<p><input type="text" id="movie_id" th:field="*{movie_id}"/></p>
<p><input type="text" id="movie_name" th:field="*{movie_name}"/></p>
<p><input type="submit" value="save" /></p>
</form>
Note that I also changed the name attribute in your inputs, for th:field. Have in mind that in order for this to work, the name of each field must match exactly the names in your objects.
Update
In case you want to set a default value to your form, without using js and since you can't combine th:field with th:value, you could set the object's attribute in your controller.
#ModelAttribute(value = "newMovie")
public Movie newMovie() {
Movie movie = new Movie();
movie.setName("Test");
return movie;
}
Update 2
If what you want is to put the current iteration of a Thymeleaf list in your form, you can do the following.
<div class="container">
<table class="table table-hover">
<tr>
<th>Id</th>
<th>Name</th>
</tr>
<tr th:each="LatestMovies : ${latestMovies}">
<td th:text="${LatestMovies.id}"></td>
<td th:text="${LatestMovies.movieName}"></td>
<td>
<form th:action="#{/save}" th:object="${LatestMovies}" method="post">
<p><input type="hidden" th:value="*{id}"/></p>
<p><input type="hidden" th:value="*{movieName}"/></p>
<p><input type="submit" value="Submit"/></p>
</form>
</td>
</tr>
</table>

You forgot to mark method param with #RequestBody annotation.

This happens because the movie object you are trying to send from the form to the controller is not mapped properly. This has as a result the constraint of the movie_id you have in your movies table (PK not null I guess) to be violated by trying to insert a not null value into it. If you want the object formed in the frontend page form to be binded in a java object you could try this
front page form
<form:form action="save" modelAttribute="movie" method="POST">
<form:label path = "movie_id"> Movie id</form:label>
<form:input path="movie_id" name="movie_id">
<form:label path = "movie_name"> Movie name</form:label>
<form:input path="movie_name" name="movie_name">
<button type="submit">save</button>
</form:form>
(you should import on your page the springframework form taglib
<%# taglib prefix="form" uri="http://www.springframework.org/tags/form"%>)
Save controller code
#PostMapping("/save")
public String save(#ModelAttribute("movie") Movie movie) {
savedMovie.save(movie);
return "redirect:/LatestMovies";
}
Of course I am assuming that your object has a similar structure like shown below
Movie class
public class Movie{
private String movie_id; // or int or long
private String movie_name;
//getters setters constructors ommitted
}

mixing up ajax and jsp to get data into a servlet

I've got a jsp file with two text fields (signUp and post). Now, I want the post text and the signUp text to be called to a servlet. Normally its going with request.getParameter(), but now I want the post text going to the servlet with an AJAX function and the signup text with the normal way (that means the name of the input within the jsp file and then request.getParameter).
Is it possible to mix both parts within one servlet because i have this:
<form name="form1" method="POST" action="PostWallServlet" id="form1">
form1 is the ajax code. I don't know how this should work. Normally there stands
`<form action="PostWallServlet" method="POST" >
and everything is callable through the Servlet. But, for now I don't know how I can mix up both components.
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PostWall pw=new PostWall();
SimpleDateFormat df = new SimpleDateFormat("YYYY/MM/DD hh:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println("Current Date Time : " + df.format(cal.getTime()));
String message = "";
String sender = request.getParameter("sender");
String post = request.getParameter("message");
String a= df.format(cal.getTime()).toString();
pw.setSender(sender);
pw.setPost(post);
pw.setDate(a);
if (pwi.addPost(pw)) {
message = "Student Successfuly Added";
} else {
message = "Student Adding Failed";
}
//RequestDispatcher rd = request.getRequestDispatcher("post.jsp");
//rd.forward(request, response);
}
$(document).ready(function(){
$('#Add').click(function(){
sendData();
});
});
function sendData(){
var mge = $('#newText').val();
alert(mge);
$.ajax({
type: "POST",
url: "PostWallServlet",
data: { message : mge }
}).done(function( msg ) {
alert( "Data Saved: " + msg );
});
}
</script>
<form name="form1" method="GET" action="PostWallServlet" id="form1"></form>
<table border="0" width="100%">
<tr>
<td colspan="3"> ${message}</td>
</tr>
<tr>
<td>Sender</td>
<td>:</td>
<td><input type="text" name="sender" value="" size=20/></td>
</tr>
<tr>
<td>Post</td>
<td>:</td>
<td><input type="text" name="post" value="" size=500 id="newText"/ ></td>
</tr>
<tr>
<td></td>
<td></td>
<td><input type="submit" value="Add" name="Add" /></td>
</tr>
</table>
Any solutions?

Put your ending tag for form AFTER all your inputs:
<form name="form1" method="GET" action="PostWallServlet" id="form1">
...
<td><input type="text" name="sender" value="" size=20 /></td>
...
<td><input type="text" name="post" value="" size=500 id="newText" /></td>
...
<td><input type="submit" value="Add" name="Add" /></td>
...
</form>
Your inputs must be INSIDE the form, not after the form.
Also make sure to end your input tags with /> not / >. You have a space between / and > on one of them.
For the Ajax part you need to give your inputs ids as well as names:
<td><input type="text" name="sender" id="sender" value="" size=20 /></td>
And then in your Ajax function for data:
data: { sender: $('#sender').val(), post: $('#post').val() }

Spring MVC getting value of element that is not an object property on the server

I have a jsp page which uses spring tag lib. I have elements on he page that is bind to properties of an object. I also have button values that are not bind to the POJO i am trying to get these values on the server. Under is the code
JSP
<body>
<form:form id="monitoringList" name="monitoringList" commandName="monitoring">
<h3>Monitoring For Criminals Victims/Wittiness</h3>
<h3>Crime Record - ${crimeRecNo}</h3>
<div id="victims">
<h3>Victims</h3>
<hr>
<input type="hidden" id="records" value="${records}"/>
<div id="citizen_row">
<label class="name"></label>
<form:input class="citizen" type="hidden" name="socialSecurityNumber" path="socialSecurityNumber"/>
<table border="1">
<tr>
<td><form:input type="hidden" path="crimeRecNo" name = "crimeRecNo"/>
<canvas id="photoCvs${citizen.socialSecurityNumber}" class="canvas" height="200" width="200"></canvas></td>
<td><label>Start Date : </label><form:input name= "monitoringStDate" path="monitoringStDate" id="monitoringStDate"/></td>
<td><label>End Date : </label><form:input name="monitoringEndDate" path="monitoringEndDate" id="monitoringEndDate"/></td>
<td>
<label>Monitoring Type : </label>
<form:select path="monitoringTypeId" name="monitoringTypeId" id="monitoringTypeId" title="Monitoring Type">
<form:options items="${monitoringType.monitoringTypeList}" itemValue="monitoringTypeId" itemLabel="monitoringTypeDesc" />
</form:select>
</td>
</tr>
</table>
<div><button id="action" onclick="submitPage('${pageContext.request.contextPath}/monitoringList.htm','POST');" type="button">Create Monitoring Records</button></div>
</div>
<!-- MySql first record starts at 0. So we need to send in the value 0 to get the first record. Create Record Navigation based on record count -->
<div id= "recordNavigation">
<c:forEach begin="0" end="${records - 1}" var="i">
<input type="submit" class="navigationbtns" id="page" onclick="submitPage('${pageContext.request.contextPath}/monitoringList.htm','POST');" value="${i}"/>
</c:forEach>
</div>
</div>
</form:form>
</body>
This is the controller and i am using request.getParameter to get the value of the button however the value id null when i click on the button which post me to the server
Controller
#RequestMapping(value = "monitoringList.htm", method = RequestMethod.POST)
public ModelAndView handleNextMonitoringPage(#ModelAttribute("crimeRecNo")Integer crimeRecNo, Model model,#ModelAttribute Monitoring monitoring, BindingResult result,ModelMap m,HttpServletRequest request,SessionStatus status, HttpSession session) throws Exception {
String p_page = request.getParameter("page");
logger.info("Page request was ::" + p_page);
//int page = 0;
myMonitoringTypeList.put("monitoringTypeList",this.monitoringTypeManager.getListOfMonitoringType());
model.addAttribute("monitoringType",myMonitoringTypeList);
Monitoring aMonitoringRecord = new Monitoring();
aMonitoringRecord = this.monitoringManager.getAMonitoringRecByCrimeRecNo(crimeRecNo, page);
int recordCount = this.monitoringManager.MonitoringRecords_RecordCount(crimeRecNo);
model.addAttribute("records",recordCount);
model.addAttribute("crimeRecNo", crimeRecNo);
model.addAttribute("monitoring", aMonitoringRecord);
return new ModelAndView(new RedirectView("monitoringList.htm"),"page",page);
}

you are missing the name attribute under which the value is being submitted
<button name="page" ....>
and
<input type="submit" name="page" ..../>

With Fields and File uploading

I have a form which contains fields and file upload elements while submitting the form it is throwing a null pointer exception, when i logged the form object all fields are getting null and when i am removing the form enctype="multipart/form-data"1 then i get all fields but the file object is getting null.
Form Code :
<form:form method="post" id="form" name="frm" action="${action}" enctype="multipart/form-data">
<table>
<tr>
<td><form:label path="productName">Product Name: </form:label></td>
<td>
<form:input path="productName"/>
</td>
</tr>
<tr>
<td><form:label path="rfile">Receipt File</form:label></td>
<td><form:input path="rfile" id="receiptFile" type="file" /></td>
</tr>
<tr>
<td colspan="2"><input type="submit" value="Upload Receipt" /></td>
</tr>
</table>
</form:form>
COntroller Code:
#RequestMapping(value="/test.do", method = RequestMethod.POST)
public ModelAndView testReceipt(#ModelAttribute("frm") ReceiptForm form, BindingResult result, HttpServletRequest request){
System.out.println("---"+form.getProductName());
System.out.println("---"+form.getRfile());
}
Please note file is a type of: CommonsMultipartFile

Use FileUpload library to parse the request from the client.