I am kind of new to Spring. I am trying to render a view based on the the value returned from DBDAOImplementation class using a conditional if statement inside processController. I am trying to return successuseraddstatus jsp file for success scenarios and faileduseraddstatus jsp file for failed scenarios.
ProcessController.java:
#RequestMapping(value = "/adduserstatus", method = RequestMethod.POST)
public String addStudent(#ModelAttribute("SpringWeb")Process process,ModelMap model) {
model.addAttribute("fname", process.getFname());
model.addAttribute("lname", process.getLname());
model.addAttribute("email", process.getEmail());
model.addAttribute("phone", process.getPhone());
ApplicationContext context =
new ClassPathXmlApplicationContext("Beans.xml");
DBDAOImp dbd =
(DBDAOImp)context.getBean("JDBCTemplate");
dbd.createuser(process.getFname(), process.getLname(), process.getEmail(), process.getPhone());
if (true){ //This is where I am having trouble
return "successuseraddstatus";
}
return "faileduseraddstatus";
}
DBDAOImplementation.java:
#Override
public Boolean createuser(String fname, String lname, String email, String phone) {
isExists(email);
if (isExists==false){
String SQL = "insert into USERS (user_id,f_name,l_name,creation_date,email,phone) values (seq_users.nextval,?,?,sysdate,?,?)";
jdbcTemplateObject.update( SQL, fname,lname,email,phone);
System.out.println("Created Record");
return true;
} else {
return false;
}
}
Below if condition works. But I am not too sure if this is the right approach.
ProcessController.java:
#RequestMapping(value = "/adduserstatus", method = RequestMethod.POST)
public String addStudent(#ModelAttribute("SpringWeb")Process process,ModelMap model) {
model.addAttribute("fname", process.getFname());
model.addAttribute("lname", process.getLname());
model.addAttribute("email", process.getEmail());
model.addAttribute("phone", process.getPhone());
DBDAOImp dbd =
(DBDAOImp)context.getBean("JDBCTemplate");
if (dbd.createuser(process.getFname(), process.getLname(), process.getEmail(), process.getPhone())){
return "useraddstatus";
} else {
return "faileduseraddstatus";
}
}
Related
I want to write a DELETE action that return a no content body if no id error exist. If id not exist I want to redirect to the coresponding GET view.
Controller code:
#RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.GET)
public String getDeleteTodo(Model model, #PathVariable("id") String id)
{
Optional<Todo> todo = todoRepository.findById(Long.decode(id));
if (todo.isEmpty()) {
model.addAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
model.addAttribute("requestedId", id);
}
else {
model.addAttribute("todo", todo.get());
}
return "v-todo-delete";
}
#RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public String deleteTodo(#PathVariable String id, RedirectAttributes redirAttrs)
{
boolean exists = todoRepository.existsById(Long.decode(id));
if (exists) {
todoRepository.deleteById(Long.decode(id));
return ""; //here I want to return a no-content body response
}
else {
redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
redirAttrs.addFlashAttribute("requestedId", id);
return "redirect:/todo/delete" + id;
}
}
More informations about the view:
The GET view is juste a view that display the todo entity corresponding to the id. The deletion is make with a button using ajax to call the DELETE method. Then response is return as 204 with no content into the body, i redirect the user with javascript to the main page... If an id not exist in the DELETE method, I want to redirect to the GET method to show an error message.
If someone have an idea to do this.
Thanks in advance.
Try using return type as ResponseEntity with whatever response body along with a response status. Please refer below code changes:
#RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public ResponseEntity deleteTodo(#PathVariable String id, RedirectAttributes redirAttrs)
{
boolean exists = todoRepository.existsById(Long.decode(id));
if (exists) {
todoRepository.deleteById(Long.decode(id));
return new ResponseEntity(HttpStatus.NO_CONTENT); //This will return No Content status
}
else {
redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
redirAttrs.addFlashAttribute("requestedId", id);
return new ResponseEntity( "redirect:/todo/delete" + id, HttpStatus.OK);
}
}
Final anwser for me:
#RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public ResponseEntity<?> deleteTodo(#PathVariable String id, RedirectAttributes redirAttrs)
{
boolean exists = todoRepository.existsById(Long.decode(id));
if (exists) {
todoRepository.deleteById(Long.decode(id));
return new ResponseEntity<>(HttpStatus.NO_CONTENT);
}
else {
redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
redirAttrs.addFlashAttribute("requestedId", id);
/* I use CONFLICT here to explain that the entity was possibly deleted
by another user between the moment the user give the view containing
the DELETE ajax link and the moment he click on it. */
return new ResponseEntity<String>( "redirect:/todo/delete" + id, HttpStatus.CONFLICT);
}
}
Thank you Mandar Dharurkar & Jeethesh Kotian for your help ;)
I have created a database called student base on the tutorial provided by tutorials point PDF, they have covered how to map the form and insert values in to the database using controllers, but they have not explained how to display the data from the database on to the webpage.
My code to list all students.
#Override
public List<Student> listStudents() {
String SQL = "select * from Student";
List<Student> students = jdbcTemplateObject.query(SQL, new StudentMapper());
return students;
}
How to call this from my controller in spring and return the list to my webpage.
My contoller is given below
#Controller
public class StudentController {
#RequestMapping(value = "/student", method = RequestMethod.GET)
public ModelAndView student()
{
return new ModelAndView("student", "command", new Student());
}
#RequestMapping(value = "/addStudent", method = RequestMethod.POST)
public String addStudent(#ModelAttribute("SpringWeb")Student student, ModelMap model)
{
ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
StudentJDBCTemplate studentJDBCTemplate = (StudentJDBCTemplate)context.getBean("studentJDBCTemplate");
studentJDBCTemplate.create(student.getName(), student.getAge());
model.addAttribute("name", student.getName());
model.addAttribute("age", student.getAge());
model.addAttribute("msg", "Student Enrolled");
return "result";
}
// How to write the listing controller?
}
From the details you provide ,
public String ListStudents(ModelMap model)
{
List<Student> list= YourServiceClassObj.listStudents();
model.addAttribute("result", list);
return "View Name here";
}
public class AccountDAO {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
public Account getAll(String user, String pass) {
String query = "SELECT * FROM dbo.USERR WHERE username=? AND password =?";
try {
conn = new DBContext().getConnection();
ps = conn.prepareStatement(query);
ps.setString(1, user);
ps.setString(2, pass);
rs = ps.executeQuery();
while (rs.next()) {
return new Account(rs.getString(1),
rs.getString(2),
rs.getString(3));
}
} catch (Exception e) {
}
return null;
}
}
your controller and service methods should be like this .and then in the view use the controller returned attribute students.
#Controller
#RequestMapping(value = "/students", method = RequestMethod.GET)
public String students(ModelMap model)
{
List<Student> students= studentService.getStudents();
model.addAttribute("students", students);
return "student/studentList.html";
}
Service :
public interface StudentService {
List<Student> getStudents();
}
#Service
public class StudentServiceImpl implements StudentService {
#Override
public List<Student> getStudents() {
return studentRepository.findAll();
}
I have following spring controller code and want to return not found status if user is not found in database, how to do it?
#Controller
public class UserController {
#RequestMapping(value = "/user?${id}", method = RequestMethod.GET)
public #ResponseBody User getUser(#PathVariable Long id) {
....
}
}
JDK8 approach:
#RequestMapping(value = "/user/{id}", method = RequestMethod.GET)
public ResponseEntity<User> getUser(#PathVariable Long id) {
return Optional
.ofNullable( userRepository.findOne(id) )
.map( user -> ResponseEntity.ok().body(user) ) //200 OK
.orElseGet( () -> ResponseEntity.notFound().build() ); //404 Not found
}
Change your handler method to have a return type of ResponseEntity. You can then return appropriately
#RequestMapping(value = "/user/{id}", method = RequestMethod.GET)
public ResponseEntity<User> getUser(#PathVariable Long id) {
User user = ...;
if (user != null) {
return new ResponseEntity<User>(user, HttpStatus.OK);
}
return new ResponseEntity<>(HttpStatus.NOT_FOUND);
}
Spring will use the same HttpMessageConverter objects to convert the User object as it does with #ResponseBody, except now you have more control over the status code and headers you want to return in the response.
With the latest update you can just use
return ResponseEntity.of(Optional<user>);
The rest is handled by below code
/**
* A shortcut for creating a {#code ResponseEntity} with the given body
* and the {#linkplain HttpStatus#OK OK} status, or an empty body and a
* {#linkplain HttpStatus#NOT_FOUND NOT FOUND} status in case of a
* {#linkplain Optional#empty()} parameter.
* #return the created {#code ResponseEntity}
* #since 5.1
*/
public static <T> ResponseEntity<T> of(Optional<T> body) {
Assert.notNull(body, "Body must not be null");
return body.map(ResponseEntity::ok).orElse(notFound().build());
}
public static ResponseEntity of(Optional body)
A shortcut for creating a ResponseEntity with the given body and the OK status, or an empty body and a NOT FOUND status in case of an Optional.empty() parameter.
#GetMapping(value = "/user/{id}")
public ResponseEntity<User> getUser(#PathVariable final Long id) {
return ResponseEntity.of(userRepository.findOne(id)));
}
public Optional<User> findOne(final Long id) {
MapSqlParameterSource paramSource = new MapSqlParameterSource().addValue("id", id);
try {
return Optional.of(namedParameterJdbcTemplate.queryForObject(SELECT_USER_BY_ID, paramSource, new UserMapper()));
} catch (DataAccessException dae) {
return Optional.empty();
}
}
it could be shorter using Method Reference operator ::
#RequestMapping(value = "/user/{id}", method = RequestMethod.GET)
public ResponseEntity<User> getUser(#PathVariable Long id) {
return Optional.ofNullable(userRepository.findOne(id))
.map(ResponseEntity::ok)
.orElse(ResponseEntity.notFound().build());
}
Need use ResponseEntity or #ResponseStatus, or with "extends RuntimeException"
#DeleteMapping(value = "")
public ResponseEntity<Employee> deleteEmployeeById(#RequestBody Employee employee) {
Employee tmp = employeeService.deleteEmployeeById(employee);
return new ResponseEntity<>(tmp, Objects.nonNull(tmp) ? HttpStatus.OK : HttpStatus.NOT_FOUND);
}
or
#ResponseStatus(value=HttpStatus.NOT_FOUND, reason="was Not Found")
I am using Spring MVC and I am making a Validator but it looks like Spring is never running it.
Here is my Validator is a easy one right now just checking for two fields
public class MemberRequestValidator implements Validator {
public boolean supports(Class aClass) {
return MemberRequest.class.equals(aClass);
}
public void validate(Object obj, Errors errors) {
MemberRequest mr = (MemberRequest) obj;
ValidationUtils.rejectIfEmptyOrWhitespace(errors, "content", "Content field is Required");
ValidationUtils.rejectIfEmptyOrWhitespace(errors, "areacode", "Area code field is Required");
}
}
Now my controller looks like the following:
#InitBinder("memberrequest")
public void initMemberRequestBinder(WebDataBinder binder) {
binder.setValidator(new MemberRequestValidator());
}
#RequestMapping(value = "/save", method = RequestMethod.POST)
public ModelAndView saveRequest(#ModelAttribute #Valid MemberRequest mr, BindingResult result)
{
if (result.hasErrors())
{
LOGGER.debug("Pages had errors on it... returning to input page");
return new ModelAndView("question");
}
else
{
String Ticket = mService.sentWebRequest(mr);
Map<String, Object> model = new HashMap<String, Object>();
Ticket t = new Ticket();
t.setTicketDetails(Ticket);
model.put("ticket", t);
return new ModelAndView("thanks", model);
}
}
and in my JSP page I have the following:
<c:url var="saveUrl" value="/mrequest/save.html" />
<form:form modelAttribute="memberrequest" action="${saveUrl}" name="memberrequest" id="memberrequest">
so if I dont enter any data in on the form I should hit the errors but I dont?
Try with #ModelAttribute("memberrequest") in handler or modelAttribute="memberRequest" in form and #initBinder("memberRequest")
I'm using the following code to bind the users to the model [to be used in the view/jsp]:
#ModelAttribute("users")
public Collection<User> populateUsers() {
return userService.findAllUsers();
}
But sometimes I just need to load few users with a particular Role, which I'm trying by using the following code:
int role = 2; //this is being set in a Controller within a method #RequestMapping(method = RequestMethod.GET) public String list(
#ModelAttribute("users")
public Collection<User> populateUsers() {
if(role == 2)
return userService.findAllUsersByRole(role);
else
return userService.findAllUsers();
}
but the populateUsers is always called at the start of the controller, before the role is set in list method, Could you please help me on how to set the users [something like late binding]
Regards
-- adding code
#Controller
#RequestMapping("/users")
public class UserController {
#Autowired
UserService userService;
#RequestMapping(method = RequestMethod.POST)
public String create(#Valid User user, BindingResult bindingResult,
Model uiModel, HttpServletRequest httpServletRequest) {
if (bindingResult.hasErrors()) {
uiModel.addAttribute("user", user);
addDateTimeFormatPatterns(uiModel);
return "users/create";
}
uiModel.asMap().clear();
userService.saveUser(user);
return "redirect:/users/"
+ encodeUrlPathSegment(user.getId().toString(),
httpServletRequest);
}
#RequestMapping(params = "form", method = RequestMethod.GET)
public String createForm(Model uiModel) {
uiModel.addAttribute("user", new User());
addDateTimeFormatPatterns(uiModel);
return "users/create";
}
#RequestMapping(value = "/{id}", method = RequestMethod.GET)
public String show(#PathVariable("id") Long id, Model uiModel) {
addDateTimeFormatPatterns(uiModel);
uiModel.addAttribute("user", userService.findUser(id));
return "users/show";
}
#RequestMapping(value = "/{id}", params = "form", method = RequestMethod.GET)
public String updateForm(#PathVariable("id") Long id, Model uiModel) {
uiModel.addAttribute("user", userService.findUser(id));
addDateTimeFormatPatterns(uiModel);
return "users/update";
}
#ModelAttribute("users")
public Collection<User> populateUsers() {
return userService.findAllUsers();
}
#ModelAttribute("userroles")
public Collection<UserRole> populateUserRoles() {
return Arrays.asList(UserRole.class.getEnumConstants());
}
void addDateTimeFormatPatterns(Model uiModel) {
uiModel.addAttribute(
"user_modified_date_format",
DateTimeFormat.patternForStyle("M-",
LocaleContextHolder.getLocale()));
}
}
#PathVariable("id") Long id is the ID I require in populateUsers, hope it is clear.
If role is in the current request, this method binding role to variable role.
#ModelAttribute("users")
public Collection<User> populateUsers(#RequestParam(required=false) Integer role) {
if(role != null && role == 2)
return userService.findAllUsersByRole(role);
else
return userService.findAllUsers();
}
Setting the model attribute in the required method has solved my issue:
model.addAttribute("users", return userService.findAllUsersByRole(role));
Thanks!