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Is it possible to paginate in jsp with JpaRepository<T, I>

I'm new to Spring boot,
I have a question that, is it possible to paginate table in JSP with JpaRepository<T, I>, I've been searching the internet for two days but haven't found one. The Query results were mostly for Thymeleaf, but I don't want to use thymeleaf. I know how to paginate in JSP using Jdbctemplate but for that, I've to write a query and the number of pages manually. I've already written a spring boot & JSP code.
EmployeeRepository:
public interface EmployeeRepository extends JpaRepository<Emp, Integer> {}
EmployeeController:
#Controller
public class EmployeeController {
#Autowired
private EmployeeRepository repo;
#GetMapping("/")
public String showPaginate(Model m, #RequestParam(defaultValue = "0") int page) {
m.addAttribute("data", repo.findAll(new PageRequest(page, 4)));
return "index";
}
}
index.jsp
<table border="2" width="70%" cellpadding="3"
class="table">
<thead class="thead-dark">
<tr align="center">
<th scope="col">Id</th>
<th scope="col">Name</th>
<th scope="col">Designation</th>
<th scope="col">Edit</th>
<th scope="col">Delete</th>
</tr>
</thead>
<c:forEach var="emp" items="${list}">
<tbody>
<tr align="center">
<td>${emp.id}</td>
<td>${emp.name}</td>
<td>${emp.designation}</td>
<td>Edit</td>
<td>Delete</td>
</tr>
</tbody>
</c:forEach>
</table>
<hr>
<!-- Pagination code will come here -->

Yes it is possible. But first you have to make an interface of PagingAndSortingRepository<T, I> repository and a controller and in your case I don't see one, you have to add a attributes of page, size, elements, stc which is returned by PagingAndSortingRepository<T, I> so your jsp page will get to know the attributes of page, etc and you can use it like ${page} to show page number. I am referring to this repository.
Employee Repository:
public interface EmployeeRepository extends PagingAndSortingRepository<Employee, Integer> {}
The PagingAndSortingRepository<T, I> has a findAll(page) method which passes the object according to page data.
Employee Dao:
#Service
public class EmpDao {
#Autowired
private EmpRepository repo;
public Page<Emp> getPage(Pageable pageable){
return repo.findAll(pageable);
}
If you want the object according to page then you have to use Page<T> interface because A page is a sublist of a list of objects. It allows gain information about the position of it in the containing entire list.
#Controller
public class EmpController {
#Autowired
private EmpDao dao;
#RequestMapping("/viewemp")
public String viewemp(Model m, Pageable pageable){
Page<Emp> pages=dao.getPage(pageable);
m.addAttribute("number", pages.getNumber());
m.addAttribute("totalPages", pages.getTotalPages());
m.addAttribute("totalElements", pages.getTotalElements());
m.addAttribute("size", pages.getSize());
m.addAttribute("data",pages.getContent());
return "viewemp";
}
}
The Pageable is an abstract interface for pagination information
getNumber()- Returns the number of the current Slice. Is always non-negative.
getTotalPages()- Returns the number of total pages.
getTotalElements()- Returns the total amount of elements.
getSize()- Returns the size of the Slice.
getContent()- Returns the page content as List.
Jsp page assuming that you already have stored data.:
Just write this in your tables body i.e <tbody>
<tbody id="myTable">
<c:choose>
<c:when test="${data.size() > 0 }">
<c:forEach var="emp" items="${data}">
<tr align="center">
<td>${emp.id}</td>
<td>${emp.name}</td>
<td>${emp.designation}</td>
<td>Edit</td>
<td>Delete</td>
</tr>
</c:forEach>
</c:when>
<c:otherwise>
<tr align="center">
<td colspan="5">No Users available</td>
</tr>
</c:otherwise>
</c:choose>
<c:if test="${data.size() > 0 }">
<div class="panel-footer">
Showing ${number+1} of ${size+1} of ${totalElements}
<ul class="pagination">
<c:forEach begin="0" end="${totalPages-1}" var="page">
<li class="page-item">
${page+1}
</li>
</c:forEach>
</ul>
</div>
</c:if>
</tbody>
and you're good to go..
Hope it helps..

There are some methods that can be determined through this example.
public class StudentRepository {
#PersistenceContext
private EntityManager entityManager;
public List<StudentEntity> listAll() {
Query query = entityManager.createQuery("from StudentEntity");
return query.getResultList();
}
}

Try this: Extend your EmployeeRepository with PagingAndSortingRepository. Then change the findall() method type PageRequest findAll(PageRequest pagerequest).
public interface EmployeeRepository extends PagingAndSortingRepository<Emp, Integer> {
PageRequest<Emp> findAll(PageRequest pagerequest)
}

How to use the two Modal Class attribute in a Spring MVC Form in java

New Registeration Form
Step 1: UserLoginDTO.java
private String userName;
private String password;
Step 2: UserInfoDTO.java
private String firstName;
private String lastName;
Step 3 : Navigating to the Registration Form
http://localhost:8080/Demo/navigate/customerRegisterForm
Controller :
#Controller
#RequestMapping("/navigate")
public class NavigationController {
#RequestMapping("/customerRegisterForm")
public String customerRegisterForm(Map modelmap) {
System.out.println("Entering the New Customer Registarion Portal... ");
UserInfoDTO infoDto = new UserInfoDTO();
UserLoginDTO loginDto = new UserLoginDTO();
modelmap.put("infoDto", infoDto);
modelmap.put("loginDto", loginDto);
return "customer/newCustomer";
}
}
Step 4 : newCustomer.jsp
<form:form method="post" modelAttribute="loginDto">
<form:input path="userName"/>
<form:input path="password"/>
<form:input path="firstName"/>
<form:input path="lastName"/>
<input type="submit" value="Add Employee"/>
</form:form>
NOTE: In Step 3, two model class are added into the modelmap and in step 4 modelAttribute="loginDto" is alone used. So the Below is error is thrown. org.springframework.beans.NotReadablePropertyException: Invalid property 'firstName' of bean class [com.pharmacy.dto.UserLoginDTO] I need to use the both model class in the view part

Add a new class FormDto having your two existing model as attribute.
public class FormDto {
private UserLoginDto loginDto;
private UserInfoDto infoDto;
//......add getter/setter
}
Modify your controller to send FormDto as modelAttribute.
#RequestMapping("/customerRegisterForm")
public String customerRegisterForm(Map modelmap) {
System.out.println("Entering the New Customer Registarion Portal... ");
FormDto formDto = new FormDto();
modelmap.put("formDto", formDto);
return "customer/newCustomer";
}
Finally, change your form attributes.
<form:form method="post" modelAttribute="formDto">
<form:input path="loginDto.userName"/>
<form:input path="loginDto.password"/>
<form:input path="infoDto.firstName"/>
<form:input path="infoDto.lastName"/>
<input type="submit" value="Add Employee"/>
</form:form>

Thymeleaf display HashMap

It may be a silly qustion, but I still cannot find an answer to it.
My Spring Boot application looks something like this:
Model:
public class Company {
public static final String URL_COMPANY = "http://193.142.112.220:8337/companyList";
private Long iD;
private String companyName;
public static Map<Long, Object> companyMap;
public Long getiD() {
return iD;
}
public void setiD(Long iD) {
this.iD = iD;
}
public String getCompanyName() {
return companyName;
}
public void setCompanyName(String companyName) {
this.companyName = companyName;
}
#Override
public String toString() {
return companyName;
}}
Controller:
#Controller
public class UrlController {
#GetMapping("/success")
public String show(Model model) {
HashMap<Long, Object> company = (HashMap<Long, Object>) Company.companyMap;
model.addAttribute("companyID", company);
return "success";
}
View:
<h1>All Companies:</h1>
<table border="1">
<tr>
<th>ID</th>
<th>Name</th>
</tr>
<tr th:each="mapEntry: ${companyID}">
<td th:text="${mapEntry.key}"></td>
<td th:text="${mapEntry.value}"></td>
</tr>
</table>
<a th:href="#{/}">Homepage</a>
</body>
</html>
So my goal is to display a table filled with Company ID's and Names. Even though, my model gets a map, I still can't see it in my browser. The table is empty.
</tr>
<tr th:each="mapEntry: {1=Tire Systems, 2=IT Enterprise, 3=Car Manufacture, 4=Electro Market}">
<td th:text=""></td>
<td th:text=""></td>
</tr>
This is what i get if i check the page source. So I clearly see, that map is loaded, but not displayed.
Moreover, a link with "homepage" does not work, and i am not sure why?
What am I missing? I am trying to fill a table with Companies, and then, using Id's of those companies, show materials attached to company via this ID. Can i use hyperlinks in table for Id's?

So you want to display a map. IF value of your map is a POJO Try something like followings
<tr><th>ID</th><th>Name</th></tr>
<tr th:each="mapEntry : ${companyID}">
<td th:text="${mapEntry.key}">keyvalue</td>
<td th:each="item : ${mapEntry.value}" th:text="${item.FIELD_NAME_OF_YOUR_POJO}">keyvalue</td>
</tr>
This should work. What i tried to show is, it is possible. The iteration depends on your data structure. If you have complex data structure iteration will change accordingly.
If value of your map is a primitive type or java reference type your current code should work. I have executed similar code like your's and it worked without any trouble. Please have a look -
HashMap<Long, Object> company = new HashMap<>();
company.put(1L, "Hello World");
model.addAttribute("companyID", company);
If value of your map is custom java type. Then follow the previous snippet.

Spring MVC how to display data from database into a table

I am very new with SPRING MVC so really I dont know much about it as of the moment. I want to display all the fields in the database in a table view how do I do this?
in my controller
#RequestMapping(value = "task", method = RequestMethod.GET)
public String taskList(Map<String, Object> model) {
model.put("task", taskRepository.findAll());
return "/tasks/list";
}
my jsp:
<%#include file="/WEB-INF/views/includes/header.jsp"%>
<h4 class="form-header">${title}</h4>
<div class="forms col-md-12 bounceInDown mainContent" data-wow-delay="0.2s">
<table class="table table-striped">
<thead>
<tr>
<th>Task ID</th>
<th>Task Name</th>
<th>Task Description</th>
</tr>
</thead>
<tbody>
<c:if test="${empty task}">
<tr>
<td colspan="8">No task to Display</td>
</tr>
</c:if>
<c:if test="${not empty task}">
<c:forEach items="${tasks}" var="task">
<tr class="">
<td>${task.taskid}</td>
<td>${task.taskName}</td>
<td>${task.taskDescription}</td>
<td>
<fmt:message key="task.list.status.text.${task.status}" />
</td>
</tr>
</c:forEach>
</c:if>
</tbody>
</table>
</div>
<%#include file="/WEB-INF/views/includes/footer.jsp"%>
i dont have anything inside my taskRepository atm

For the starters:
#RequestMapping(value = "task", method = RequestMethod.GET)
public String taskList(Map<String, Object> model) {
model.put("task", taskRepository.findAll());
return "/tasks/list";
}
You should return some object you have created instead of String value. Let's asume you want to transfer two fields to you page lets name them field1 and field2. Now create your Data Transfer Object:
public class MyEntityDto{
private String filed1;
private String field2;
//Getter and setter method
.
.
.
}
Now your controller should look something like this:
#Autowired
SomeSevice someService;
#RequestMapping(value = "task", method = RequestMethod.GET)
#ResponseBody
public List<MyEntityDto> taskList(Map<String, Object> model) {
List<MyEntityDto> dtoList = someService.findALl();
return dtoList;
}
Your service from the other hand should look something like this:
#Service
public class SomeService(){
#Autowired
TaskRepository taskRepository;
public List<MyEntityDto> findAll(){
return assemblyTasks(taskRepository.findAll());//TODO implement method assemblyTasks
}
}
Notice that I put your repository usage into the service.This is the way it supposed to be done. You should use services in order to fetch data from your database and than you want to return your data using specificlly design for that purpose object - Data Transfer Object.
I leave the implementation of assemblyTask method to you. What you need to do there is to assign fields you want to pass from entity to view through your dto object. Generally you would want to have an assembler class for every DTO object but for the sake of simplicity I introduced the idea by using method. If you want to read more about DTO, view this post:
getting-value-of-invalid-field-after-methodargumentnotvalidexception
If you are completely new to the Spring world I recommend also find some basics web tutorials, for example here:
gonetoseries

How to bind spring MVC jsp page to two classes

I have two classes Person and Passport. Passport has foreignkey = personid.
This is my controller
model.addAttribute("personAttribute", new Person());
JSP PAge
<form:form modelAttribute="personAttribute" method="POST" action="${saveUrl}">
<table>
<tr>
<td><form:label path="firstName">First Name:</form:label></td>
<td><form:input path="firstName"/></td>
<td><form:errors path="firstName"/>gfgf</td>
</tr>
<td><form:label path="country_issue">Passport:</form:label></td>
<td><form:input path="country_issue"/></td>
<td><form:errors path="country_issue"/></td>
NOw i want to put country_issue in other passport table.
I don't have that column in Person so how will i bind that in JSP page
Passport has only id , person_id, country_issue field

All you have to do is wrap your form backing objects in a form:
public class MyForm
{
private final Person person;
private final Passport passport;
public MyForm()
{
this.person = new Person();
this.passport = new Passport();
}
public MyForm(Person person, Passport passport)
{
this.person = person;
this.passport = passport;
}
// getters & setters
}
Then in your controller:
model.addAttribute("myForm", new MyForm());
or you could do
model.addAttribute("myForm", new MyForm(personService.findPerson(1), passportService.findPassport(1)));
and in your jsp:
<form:form modelAttribute="myForm" method="POST" action="${saveUrl}">
<table>
<tr>
<td><form:label path="person.firstName">First Name:</form:label></td>
<td><form:input path="person.firstName"/></td>
<td><form:errors path="person.firstName"/>gfgf</td>
</tr>
<tr>
<td><form:label path="passport.country_issue">Passport:</form:label></td>
<td><form:input path="passport.country_issue"/></td>
<td><form:errors path="passport.country_issue"/></td>
<tr/>
</table>
</form>

I would suggest you to create a class that maps your GUI form 1:1 and then write a transformer/validator. This class should ideally be package-private (maybe even inner class) for your GUI element so it doesn't mix with the DAO objects, such as Person or Passport.

UI data is managed best with Classes like TransferObjects are ModelObjects which represent the page data binding requirements. If we do that we can move the concern to the controller to extract out the spring (persistent) objects from the UI object.
If the object is called PassportForm then the method passportForm.person() and passportForm.Passport() should give you the persistent object. In this way we can also eliminate the need for transformer/validator classes and push the behavior into the objects.