===============================update====================================
try{
// snip
while (rs.next()) {
BookListEntity entity = new BookListEntity();
entity.setId(rs.getInt("id"));
entity.setName(rs.getString("name"));
entity.setSubject(rs.getString("subject"));
entity.setInsertTime(rs.getString("insert_time"));
entity.setRentalCheck(rs.getInt("rental_check"));
BookList.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
}
model.addAttribute("TestList",BookList);
this is first controller
-> get BookList to "TestList" and move to view(jsp)
<c:forEach var="listValue" items="${TestList}">
<form action="rentalandreturn.do" method="post">
<tr class="active">
<td><c:out value="${listValue.id}" /></td>
<td><c:out value="${listValue.name}" /></td>
<td><c:out value="${listValue.subject}" /></td>
<td><c:out value="${listValue.insertTime}" /></td>
<c:if test="${listValue.rentalCheck eq 1}">
<td>
<input type="submit" value="貸し出しする" />
</td>
</c:if>
<c:if test="${listValue.rentalCheck eq 0}">
<td><input type="submit" value="返納する" /></td>
</c:if>
</tr>
</form>
</c:forEach>
This is jsp(view) code
->and I want to use c:out value something do
#Controller
public class Rentalandreturn {
#RequestMapping(value = "rentalandreturn", method = RequestMethod.POST)
public String rentalandreturn(HttpServletRequest request, Model model) {
//How can i get c:out value?
String id = (String) request.getAttribute("value");
System.out.println(id);
return "BookList";
}
}
and this is second java code(Controller)
-> I want to get c:out value what I print view page.
is there any way to get c:out value in Controller(=java code)?
sorry about my English. if you don't understand my question. say to comment.
you can not read directly in controller class as it is in , better to write a javascript code to to read the data and from that on an action you can send to controller.
I'm building a blog in Java using Spring and Hibernate. I can't seem to figure out what is going on but I keep running into a Bad Request error when I try to add (save) a post and I can't figure out where I am wrong in my mapping.
Error message:
Controller:
#Controller
#RequestMapping("/blog")
public class IndexController {
#Autowired
private PostService postService;
#RequestMapping("/list")
public String showPage (Model theModel) {
// get posts from DAO
List<Post> thePosts = postService.getAllPosts();
// add the posts to the model
theModel.addAttribute("allPosts", thePosts);
return "allPosts";
}
#GetMapping("/showFormForAdd")
public String showFormForAdd(Model theModel) {
//create model attribute to bind form data
Post thePost = new Post();
theModel.addAttribute("post", thePost);
return "postSuccess";
}
#PostMapping("/savePost")
public String savePost(#ModelAttribute("post") Post thePost) {
// save the post using our service
postService.savePost(thePost);
return "allPosts";
}
Form snippet:
<div class="table" id="container">
<form:form action="savePost" modelAttribute="post"
method="POST">
<table>
<tbody>
<tr>
<td><label>Title:</label></td>
<td><form:input path="title" /></td>
</tr>
<tr>
<td><label>Author:</label></td>
<td><form:input path="author" /></td>
</tr>
<tr>
<td><label>Date:</label></td>
<td><form:input path="date" /></td>
</tr>
<tr>
<td><label>Post:</label></td>
<td><form:input path="post" /></td>
</tr>
<tr>
<td><label></label></td>
<td><input type="submit" value="Save"></td>
</tr>
</tbody>
</table>
</form:form>
<div style="clear: both;"></div>
<p>
Back to Home Page
</p>
</div>
All other pages are working correctly so far, just can't add an actual blog post. Any help is greatly appreciated.
I figured this out and it is similar to another spring issue I had in the past.
I don't think this really follows a lot of conventional function/design theory, but I added some code into the controller and it now works. I can add a post easily.
First thing was, I removed the #ModelAttribute tag from my "savePost" method. Then I added #RequestParam to my method parameters. Added a little bit of logic and now it saves to the database and then appears on the blog. Good stuff.
Code:
#PostMapping("/savePost")
public String savePost(#RequestParam("author") String author,
#RequestParam("title") String title, #RequestParam("date") String date,
#RequestParam("post") String post) throws ParseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date theDate = sdf.parse(date);
// save the customer using our service
Post thePost = new Post();
thePost.setAuthor(author);
thePost.setDate(theDate);
thePost.setTitle(title);
thePost.setPost(post);
postService.addPost(thePost);
System.out.println(thePost.toString()); //testing
return "success";
}
jsp:
<form:form action="savePost" modelAttribute="post" method="POST">
<table>
<tbody>
<tr>
<td><label>Title:</label></td>
<td><input id="title" type="text" name="title"></td>
</tr>
<tr>
<td><label>Author:</label></td>
<td><input id="author" type="text" name="author"></td>
</tr>
<tr>
<td><label>Date:</label></td>
<td><input id="date" type="text" name="date"></td>
</tr>
<tr>
<td><label>Post:</label></td>
<td><textarea id="post" type="text"
name="post"></textarea></td>
</tr>
<tr>
<td><label></label></td>
<td><input type="submit" value="Save"></td>
</tr>
</tbody>
</table>
</form:form>
I am having a lot of difficulty with POSTing back a form to the controller, which should contain simply an arraylist of objects that the user may edit.
The form loads up correctly, but when it's posted, it never seems to actually post anything.
Here is my form:
<form action="#" th:action="#{/query/submitQuery}" th:object="${clientList}" method="post">
<table class="table table-bordered table-hover table-striped">
<thead>
<tr>
<th>Select</th>
<th>Client ID</th>
<th>IP Addresss</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr th:each="currentClient, stat : ${clientList}">
<td><input type="checkbox" th:checked="${currentClient.selected}" /></td>
<td th:text="${currentClient.getClientID()}" ></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}" ></td>
</tr>
</tbody>
</table>
<button type="submit" value="submit" class="btn btn-success">Submit</button>
</form>
Above works fine, it loads up the list correctly. However, when I POST, it returns a empty object (of size 0). I believe this is due to the lack of th:field, but anyway here is controller POST method:
...
private List<ClientWithSelection> allClientsWithSelection = new ArrayList<ClientWithSelection>();
//GET method
...
model.addAttribute("clientList", allClientsWithSelection)
....
//POST method
#RequestMapping(value="/submitQuery", method = RequestMethod.POST)
public String processQuery(#ModelAttribute(value="clientList") ArrayList clientList, Model model){
//clientList== 0 in size
...
}
I have tried adding a th:field but regardless of what I do, it causes an exception.
I've tried:
...
<tr th:each="currentClient, stat : ${clientList}">
<td><input type="checkbox" th:checked="${currentClient.selected}" th:field="*{}" /></td>
<td th th:field="*{currentClient.selected}" ></td>
...
I cannot access currentClient (compile error), I can't even select clientList, it gives me options like get(), add(), clearAll() etc, so it things it should have an array, however, I cannot pass in an array.
I've also tried using something like th:field=${}, this causes runtime exception
I've tried
th:field = "*{clientList[__currentClient.clientID__]}"
but also compile error.
Any ideas?
UPDATE 1:
Tobias suggested that I need to wrap my list in a wraapper. So that's what I did:
ClientWithSelectionWrapper:
public class ClientWithSelectionListWrapper {
private ArrayList<ClientWithSelection> clientList;
public List<ClientWithSelection> getClientList(){
return clientList;
}
public void setClientList(ArrayList<ClientWithSelection> clients){
this.clientList = clients;
}
}
My page:
<form action="#" th:action="#{/query/submitQuery}" th:object="${wrapper}" method="post">
....
<tr th:each="currentClient, stat : ${wrapper.clientList}">
<td th:text="${stat}"></td>
<td>
<input type="checkbox"
th:name="|clientList[${stat.index}]|"
th:value="${currentClient.getClientID()}"
th:checked="${currentClient.selected}" />
</td>
<td th:text="${currentClient.getClientID()}" ></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}" ></td>
</tr>
Above loads fine:
Then my controller:
#RequestMapping(value="/submitQuery", method = RequestMethod.POST)
public String processQuery(#ModelAttribute ClientWithSelectionListWrapper wrapper, Model model){
...
}
The page loads correctly, the data is displayed as expected. If I post the form without any selection I get this:
org.springframework.expression.spel.SpelEvaluationException: EL1007E:(pos 0): Property or field 'clientList' cannot be found on null
Not sure why it's complaining
(In the GET Method it has: model.addAttribute("wrapper", wrapper);)
If I then make a selection, i.e. tick the first entry:
There was an unexpected error (type=Bad Request, status=400).
Validation failed for object='clientWithSelectionListWrapper'. Error count: 1
I'm guessing my POST controller is not getting the clientWithSelectionListWrapper. Not sure why, since I have set the wrapper object to be posted back via the th:object="wrapper" in the FORM header.
UPDATE 2:
I've made some progress! Finally the submitted form is being picked up by the POST method in controller. However, all the properties appear to be null, except for whether the item has been ticked or not. I've made various changes, this is how it is looking:
<form action="#" th:action="#{/query/submitQuery}" th:object="${wrapper}" method="post">
....
<tr th:each="currentClient, stat : ${clientList}">
<td th:text="${stat}"></td>
<td>
<input type="checkbox"
th:name="|clientList[${stat.index}]|"
th:value="${currentClient.getClientID()}"
th:checked="${currentClient.selected}"
th:field="*{clientList[__${stat.index}__].selected}">
</td>
<td th:text="${currentClient.getClientID()}"
th:field="*{clientList[__${stat.index}__].clientID}"
th:value="${currentClient.getClientID()}"
></td>
<td th:text="${currentClient.getIpAddress()}"
th:field="*{clientList[__${stat.index}__].ipAddress}"
th:value="${currentClient.getIpAddress()}"
></td>
<td th:text="${currentClient.getDescription()}"
th:field="*{clientList[__${stat.index}__].description}"
th:value="${currentClient.getDescription()}"
></td>
</tr>
I also added a default param-less constructor to my wrapper class and added a bindingResult param to POST method (not sure if needed).
public String processQuery(#ModelAttribute ClientWithSelectionListWrapper wrapper, BindingResult bindingResult, Model model)
So when an object is being posted, this is how it is looking:
Of course, the systemInfo is supposed to be null (at this stage), but the clientID is always 0, and ipAddress/Description always null. The selected boolean is correct though for all properties. I'm sure I've made a mistake on one of the properties somewhere. Back to investigation.
UPDATE 3:
Ok I've managed to fill up all the values correctly! But I had to change my td to include an <input /> which is not what I wanted... Nonetheless, the values are populating correctly, suggesting spring looks for an input tag perhaps for data mapping?
Here is an example of how I changed the clientID table data:
<td>
<input type="text" readonly="readonly"
th:name="|clientList[${stat.index}]|"
th:value="${currentClient.getClientID()}"
th:field="*{clientList[__${stat.index}__].clientID}"
/>
</td>
Now I need to figure out how to display it as plain data, ideally without any presence of an input box...
You need a wrapper object to hold the submited data, like this one:
public class ClientForm {
private ArrayList<String> clientList;
public ArrayList<String> getClientList() {
return clientList;
}
public void setClientList(ArrayList<String> clientList) {
this.clientList = clientList;
}
}
and use it as the #ModelAttribute in your processQuery method:
#RequestMapping(value="/submitQuery", method = RequestMethod.POST)
public String processQuery(#ModelAttribute ClientForm form, Model model){
System.out.println(form.getClientList());
}
Moreover, the input element needs a name and a value. If you directly build the html, then take into account that the name must be clientList[i], where i is the position of the item in the list:
<tr th:each="currentClient, stat : ${clientList}">
<td><input type="checkbox"
th:name="|clientList[${stat.index}]|"
th:value="${currentClient.getClientID()}"
th:checked="${currentClient.selected}" />
</td>
<td th:text="${currentClient.getClientID()}" ></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}" ></td>
</tr>
Note that clientList can contain null at
intermediate positions. Per example, if posted data is:
clientList[1] = 'B'
clientList[3] = 'D'
the resulting ArrayList will be: [null, B, null, D]
UPDATE 1:
In my exmple above, ClientForm is a wrapper for List<String>. But in your case ClientWithSelectionListWrapper contains ArrayList<ClientWithSelection>. Therefor clientList[1] should be clientList[1].clientID and so on with the other properties you want to sent back:
<tr th:each="currentClient, stat : ${wrapper.clientList}">
<td><input type="checkbox" th:name="|clientList[${stat.index}].clientID|"
th:value="${currentClient.getClientID()}" th:checked="${currentClient.selected}" /></td>
<td th:text="${currentClient.getClientID()}"></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}"></td>
</tr>
I've built a little demo, so you can test it:
Application.java
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
ClientWithSelection.java
public class ClientWithSelection {
private Boolean selected;
private String clientID;
private String ipAddress;
private String description;
public ClientWithSelection() {
}
public ClientWithSelection(Boolean selected, String clientID, String ipAddress, String description) {
super();
this.selected = selected;
this.clientID = clientID;
this.ipAddress = ipAddress;
this.description = description;
}
/* Getters and setters ... */
}
ClientWithSelectionListWrapper.java
public class ClientWithSelectionListWrapper {
private ArrayList<ClientWithSelection> clientList;
public ArrayList<ClientWithSelection> getClientList() {
return clientList;
}
public void setClientList(ArrayList<ClientWithSelection> clients) {
this.clientList = clients;
}
}
TestController.java
#Controller
class TestController {
private ArrayList<ClientWithSelection> allClientsWithSelection = new ArrayList<ClientWithSelection>();
public TestController() {
/* Dummy data */
allClientsWithSelection.add(new ClientWithSelection(false, "1", "192.168.0.10", "Client A"));
allClientsWithSelection.add(new ClientWithSelection(false, "2", "192.168.0.11", "Client B"));
allClientsWithSelection.add(new ClientWithSelection(false, "3", "192.168.0.12", "Client C"));
allClientsWithSelection.add(new ClientWithSelection(false, "4", "192.168.0.13", "Client D"));
}
#RequestMapping("/")
String index(Model model) {
ClientWithSelectionListWrapper wrapper = new ClientWithSelectionListWrapper();
wrapper.setClientList(allClientsWithSelection);
model.addAttribute("wrapper", wrapper);
return "test";
}
#RequestMapping(value = "/query/submitQuery", method = RequestMethod.POST)
public String processQuery(#ModelAttribute ClientWithSelectionListWrapper wrapper, Model model) {
System.out.println(wrapper.getClientList() != null ? wrapper.getClientList().size() : "null list");
System.out.println("--");
model.addAttribute("wrapper", wrapper);
return "test";
}
}
test.html
<!DOCTYPE html>
<html>
<head></head>
<body>
<form action="#" th:action="#{/query/submitQuery}" th:object="${wrapper}" method="post">
<table class="table table-bordered table-hover table-striped">
<thead>
<tr>
<th>Select</th>
<th>Client ID</th>
<th>IP Addresss</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr th:each="currentClient, stat : ${wrapper.clientList}">
<td><input type="checkbox" th:name="|clientList[${stat.index}].clientID|"
th:value="${currentClient.getClientID()}" th:checked="${currentClient.selected}" /></td>
<td th:text="${currentClient.getClientID()}"></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}"></td>
</tr>
</tbody>
</table>
<button type="submit" value="submit" class="btn btn-success">Submit</button>
</form>
</body>
</html>
UPDATE 1.B:
Below is the same example using th:field and sending back all other attributes as hidden values.
<tbody>
<tr th:each="currentClient, stat : *{clientList}">
<td>
<input type="checkbox" th:field="*{clientList[__${stat.index}__].selected}" />
<input type="hidden" th:field="*{clientList[__${stat.index}__].clientID}" />
<input type="hidden" th:field="*{clientList[__${stat.index}__].ipAddress}" />
<input type="hidden" th:field="*{clientList[__${stat.index}__].description}" />
</td>
<td th:text="${currentClient.getClientID()}"></td>
<td th:text="${currentClient.getIpAddress()}"></td>
<td th:text="${currentClient.getDescription()}"></td>
</tr>
</tbody>
When you want to select objects in thymeleaf, you dont actually need to create a wrapper for the purpose of storing a boolean select field. Using dynamic fields as per the thymeleaf guide with syntax th:field="*{rows[__${rowStat.index}__].variety}" is good for when you want to access an already existing set of objects in a collection. Its not really designed for doing selections by using wrapper objects IMO as it creates unnecessary boilerplate code and is sort of a hack.
Consider this simple example, a Person can select Drinks they like. Note: Constructors, Getters and setters are omitted for clarity. Also, these objects are normally stored in a database but I am using in memory arrays to explain the concept.
public class Person {
private Long id;
private List<Drink> drinks;
}
public class Drink {
private Long id;
private String name;
}
Spring controllers
The main thing here is that we are storing the Person in the Model so we can bind it to the form within th:object.
Secondly, the selectableDrinks are the drinks a person can select on the UI.
#GetMapping("/drinks")
public String getDrinks(Model model) {
Person person = new Person(30L);
// ud normally get these from the database.
List<Drink> selectableDrinks = Arrays.asList(
new Drink(1L, "coke"),
new Drink(2L, "fanta"),
new Drink(3L, "sprite")
);
model.addAttribute("person", person);
model.addAttribute("selectableDrinks", selectableDrinks);
return "templates/drinks";
}
#PostMapping("/drinks")
public String postDrinks(#ModelAttribute("person") Person person) {
// person.drinks will contain only the selected drinks
System.out.println(person);
return "templates/drinks";
}
Template code
Pay close attention to the li loop and how selectableDrinks is used to get all possible drinks that can be selected.
The checkbox th:field really expands to person.drinks since th:object is bound to Person and *{drinks} simply is the shortcut to referring to a property on the Person object. You can think of this as just telling spring/thymeleaf that any selected Drinks are going to be put into the ArrayList at location person.drinks.
<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml"
xmlns:th="http://www.thymeleaf.org"
xmlns:layout="http://www.ultraq.net.nz/thymeleaf/layout" >
<body>
<div class="ui top attached segment">
<div class="ui top attached label">Drink demo</div>
<form class="ui form" th:action="#{/drinks}" method="post" th:object="${person}">
<ul>
<li th:each="drink : ${selectableDrinks}">
<div class="ui checkbox">
<input type="checkbox" th:field="*{drinks}" th:value="${drink.id}">
<label th:text="${drink.name}"></label>
</div>
</li>
</ul>
<div class="field">
<button class="ui button" type="submit">Submit</button>
</div>
</form>
</div>
</body>
</html>
Any way...the secret sauce is using th:value=${drinks.id}. This relies on spring converters. When the form is posted, spring will try recreate a Person and to do this it needs to know how to convert any selected drink.id strings into the actual Drink type. Note: If you did th:value${drinks} the value key in the checkbox html would be the toString() representation of a Drink which is not what you want, hence need to use the id!. If you are following along, all you need to do is create your own converter if one isn't already created.
Without a converter you will receive an error like
Failed to convert property value of type 'java.lang.String' to required type 'java.util.List' for property 'drinks'
You can turn on logging in application.properties to see the errors in detail.
logging.level.org.springframework.web=TRACE
This just means spring doesn't know how to convert a string id representing a drink.id into a Drink. The below is an example of a Converter that fixes this issue. Normally you would inject a repository in get access the database.
#Component
public class DrinkConverter implements Converter<String, Drink> {
#Override
public Drink convert(String id) {
System.out.println("Trying to convert id=" + id + " into a drink");
int parsedId = Integer.parseInt(id);
List<Drink> selectableDrinks = Arrays.asList(
new Drink(1L, "coke"),
new Drink(2L, "fanta"),
new Drink(3L, "sprite")
);
int index = parsedId - 1;
return selectableDrinks.get(index);
}
}
If an entity has a corresponding spring data repository, spring automatically creates the converters and will handle fetching the entity when an id is provided (string id seems to be fine too so spring does some additional conversions there by the looks). This is really cool but can be confusing to understand at first.
I have a problem while creating a with a default value contained in my current object.
The value is correctly set in the field, but when I submit the form, the default value is still there, even if the user chose another value in the list...
Here is my controller :
#RequestMapping(method = RequestMethod.GET)
public String createForm(final ModelMap modelMap){
User user;
user = new User();
user.setGroup("HelpDesk");
user.setName("John");
ArrayList<String> groupList = new ArrayList<>();
groupList.add("Admin");
groupList.add("HelpDesk");
groupList.add("GroupManager");
groupList.add("Others");
modelMap.addAttribute("user", user);
modelMap.addAttribute("groupList", groupList);
return "/user/user-add";
}
#RequestMapping(method = RequestMethod.POST)
public String createUser(#ModelAttribute("user") final User user, BindingResult result) {
userValidator.validate(user, result, groupList);
logger.info(user.getGroup()); //Will print "HelpDesk,Admin" for instance
return "...";
}
And here is my JSP :
<table>
<form:form method="POST" modelAttribute="user">
<tr>
<td>Name:</td>
<td><form:input path="name"/></td>
<td><form:errors path="name" cssClass="error" /></td>
</tr>
<tr>
<td>Group:</td>
<td><form:select path="group" items="${groupList}" multiple="single"/></td>
<td><form:errors path="group" cssClass="error" /></td>
</tr>
<tr>
<td colspan="3"><input type="submit" /></td>
</tr>
</form:form>
</table>
For instance, if i choose "Admin" in the select list, i'll get "HelpDesk, Admin" in the property "group" of my user after submitting the form...
What am i doing wrong?
Thanks for your help!
Can I see your "POST" method or the "onSubmit" method? In your post method you must specify the User object as your model attribute or command.
In my application, I have the following Constants class
public class Constants {
...
public static final int MAX_NUM_OF_PICTURES = 2
...
}
Earlier when I was using JSP, I managed to dynamically render input fields for uploading files based on this constant as following:
<%
for (int i = 1; i < Constants.MAX_NUM_OF_PICTURES + 1; i++) {
%>
<tr>
<td>Upload Picture <%= i %></td>
<td><input name="<%= i%>" type="file" /></td>
</tr>
<tr>
<td>Description <%= i %></td>
<td><input type="text" name="<%= "description" + i%>" id="description" /></td>
</tr>
<%
}
%>
Currently, I am trying to use JSF to achieve the above task. If these input fields are not dynamically generated, I can easily define the following properties in my backing bean:
#ManagedBean
#RequestScoped
public class MrBean {
...
private UploadedFile picture1;
private String pictDescription1;
...
}
However, since these fields are now dynamically generated, I cannot know how many properties I would need to define in advance to capture these uploaded files.
I'd be very grateful if someone could give me an advice on how I should tackle this problem?
Best regards,
James Tran
Put those properties in another javabean class and have a collection of those javabeans in your managed bean.
E.g.
public class Picture {
private UploadedFile file;
private String description;
// ...
}
and
#ManagedBean
#ViewScoped
public class Profile {
List<Picture> pictures;
public Profile() {
pictures = new ArrayList<Picture>();
for (int i = 0; i < Constants.MAX_NUM_OF_PICTURES; i++) {
pictures.add(new Picture());
}
}
// ...
}
Then you can loop over it in for example <ui:repeat> (or maybe <h:dataTable>, but this isn't really suitable if you want two repeating rows instead of one).
<table>
<ui:repeat value="#{profile.pictures}" var="picture" varStatus="loop">
<tr>
<td>Upload Picture #{loop.index + 1}</td>
<td><t:inputFileUpload value="#{picture.file}" /></td>
</tr>
<tr>
<td>Description #{loop.index + 1}</td>
<td><h:inputText value="#{picture.description}" /></td>
</tr>
</ui:repeat>
</table>
I have no idea what component library you're using for uploading files, so I assumed it be just Tomahawk.