I want to pass some variables to my server. I did it this way, like shown in the example:
#Controller
#RequestMapping("/owners/{ownerId}")
public class RelativePathUriTemplateController {
#RequestMapping("/pets/{petId}")
public void findPet(#PathVariable String ownerId, #PathVariable String petId, Model model) {
// implementation omitted
}
}
This works totally fine when I send a request like this:
domain/owners/123/pets/123
But what I want to do is getting all pets of one owner. This means I dont need/want to pass a pet-ID:
domain/owners/123/pets/
But then I get an Excpetion that there is no Handler for this request. Is it possible to send a request like this or is it limited by Spring?
You have to add a second method:
#RequestMapping("/pets/")
public void findPetByOwner(#PathVariable String ownerId Model model) {
// implementation omitted
}
Related
I have a quick question. I`m sending two params in a json object (user) from angular to my spring app using POST. When I display this object it is:
System.out.println(user.email);
{email=example#example.com, password=gfdgdfgf}
In Java my code is:
#RequestMapping(value="/userLogin", method = RequestMethod.POST)
public boolean userLogin(#RequestBody Object user, ModelMap model) {
...
}
But when I try to display the field from this object like:
user.password, it doesn`t work.
Many thanks for help!
You are mapping your data to an Object, which lacks the needed fields(email and password). You should create an entity class and use it instead. Jackson should be able to map your passed parameters.
public class User{
public String email;
public String password;
/* ... */
}
I have many controllers in my Spring MVC web application and there is a param mandatoryParam let's say which has to be present in all the requests to the web application.
Now I want to make that param-value available to all the methods in my web-layer and service-layer. How can I handle this scenario effectively?
Currently I am handling it in this way:
... controllerMethod(#RequestParam String mandatoryParam, ...)
and, then passing this param to service layer by calling it's method
#ControllerAdvice("net.myproject.mypackage")
public class MyControllerAdvice {
#ModelAttribute
public void myMethod(#RequestParam String mandatoryParam) {
// Use your mandatoryParam
}
}
myMethod() will be called for every request to any controller in the net.myproject.mypackage package. (Before Spring 4.0, you could not define a package. #ControllerAdvice applied to all controllers).
See the Spring Reference for more details on #ModelAttribute methods.
Thanks Alexey for leading the way.
His solution is:
Add a #ControllerAdvice triggering for all controllers, or selected ones
This #ControllerAdvice has a #PathVariable (for a "/path/{variable}" URL) or a #RequestParam (for a "?variable=..." in URL) to get the ID from the request (worth mentioning both annotations to avoid blind-"copy/past bug", true story ;-) )
This #ControllerAdvice then populates a model attribute with the data fetched from database (for instance)
The controllers with uses #ModelAttribute as method parameters to retrieve the data from the current request's model
I'd like to add a warning and a more complete example:
Warning: see JavaDoc for ModelAttribute.name() if no name is provided to the #ModelAttribute annotation (better to not clutter the code):
The default model attribute name is inferred from the declared
attribute type (i.e. the method parameter type or method return type),
based on the non-qualified class name:
e.g. "orderAddress" for class "mypackage.OrderAddress",
or "orderAddressList" for "List<mypackage.OrderAddress>".
The complete example:
#ControllerAdvice
public class ParentInjector {
#ModelAttribute
public void injectParent(#PathVariable long parentId, Model model) {
model.addAttribute("parentDTO", new ParentDTO(parentId, "A faked parent"));
}
}
#RestController
#RequestMapping("/api/parents/{parentId:[0-9]+}/childs")
public class ChildResource {
#GetMapping("/{childId:[0-9]+}")
public ChildDTO getOne(#ModelAttribute ParentDTO parent, long childId) {
return new ChildDTO(parent, childId, "A faked child");
}
}
To continue about the warning, requests are declaring the parameter "#ModelAttribute ParentDTO parent": the name of the model attribute is not the variable name ("parent"), nor the original "parentId", but the classname with first letter lowerified: "parentDTO", so we have to be careful to use model.addAttribute("parentDTO"...)
Edit: a simpler, less-error-prone, and more complete example:
#Target(ElementType.TYPE)
#Retention(RetentionPolicy.RUNTIME)
#Documented
#RestController
public #interface ProjectDependantRestController {
/**
* The value may indicate a suggestion for a logical component name,
* to be turned into a Spring bean in case of an autodetected component.
*
* #return the suggested component name, if any
*/
String value() default "";
}
#ControllerAdvice(annotations = ParentDependantRestController.class)
public class ParentInjector {
#ModelAttribute
public ParentDTO injectParent(#PathVariable long parentId) {
return new ParentDTO(parentId, "A faked parent");
}
}
#ParentDependantRestController
#RequestMapping("/api/parents/{parentId:[0-9]+}/childs")
public class ChildResource {
#GetMapping("/{childId:[0-9]+}")
public ChildDTO getOne(#ModelAttribute ParentDTO parent, long childId) {
return new ChildDTO(parent, childId, "A faked child");
}
}
I've a legacy system where query parameters are used to determine the class/method for a request using a simple in-house framework. E.g.
/endpoint?product=foo&action=bar&amount=1.0
/endpoint?product=foo&action=baz&amount=1.0
And I'd like map all actions for a product to one class so the plumbing can be greatly simplified, e.g.
#Controller
#RequestMapping("/endpoint/foo/**")
public class FooController {
#AutoWire
private FooProductService s; // one of many beans that have to be wired into lots of classes
#RequestMapping("/bar")
public void bar(#PathVariable String amount, Model model) {
// implementation omitted
}
#RequestMapping("/baz")
public void baz(#PathVariable String amount, Model model) {
// implementation omitted
}
}
It's a published API so we can't change the public API -> the URLs cannot change.
I thought that perhaps this could be done using configuration, as aspect or even a custom framework with out own annotations.
I believe you can do something like this for product=foo&action=bar&amount=1.0
#RequestMapping(value = "product={productName}&action={someaction}&amount={value}", method=RequestMethod.GET)
something(#PathVariable String productName, #PathVariable String someaction, #PathVariable String value)
if(someaction.equals("bar")) {
//do bar
}
if(someaction.equals("baz")) {
//do baz
}
}
HTH
I'm getting some weird binding issue with Spring MVC 3.
My Controller request mapping looks like this:
#RequestMapping
public String save(HttpServletRequest req,
#ModelAttribute("userEditForm") UserEditForm form,
BindingResult formBindingResult,
ModelMap model,
#ModelAttribute("session") AdminSession session) {
// some validation etc
}
The UserEditForm:
public class UserEditForm {
private User user;
public User getUser() { ... }
public void setUser(User user) { ... }
}
The AdminSession:
public class AdminSession {
private User user;
public User getUser() { ... }
public void setUser() { ...}
}
What's happening is that when I submit my form, Spring is binding the User as I expect in my UserEditForm object, however, the AdminSession is also having it's User bound by Spring, in so far as it's property values are also updated.
I'm going to assume it's due to having a user property in both #ModelAttribute objects.
I thought that having the BindingResult after the UserEditForm form in the method signature would stop this? The objects are separate instances, and my form elements reference the UserEditForm object:
<#spring.bind "userEditForm.user.name" />
<input name="${spring.status.expression}" />
I've noticed that in the generated HTML it's outputting:
<input name="user.name" />
Hardcoding the name as userEditForm.user.name gives me errors, so that's not the way forward.
Is there anyway to stop this from happening?
That's the default behavior when you annotate a handler method parameter with the #ModelAttribute. Spring takes the request properties and matches them to properties of the objects annotated with #ModelAttribute. That's what Spring looks at when deciding what to do: your annotations.
Since both UserEditForm and AdminSession are annotated with #ModelAttribute and both have a User property, a request property named user.name will get bound to both User properties.
You tried to include the command name in the input name and got an error. That's because when binding occurs it occurs on your command object and Spring looks for properties on it (the bindinf path is relative to the command object) and off course the expression does not find any property with that name. If you want to use a full name you could wrap the form in another object and use that for your command instead, something like this:
public class UserEditFormWrapper {
private UserEditForm form;
public UserEditForm getForm() {
return form;
}
public void setForm(UserEditForm form) {
this.form = form;
}
}
Now you can use an expression like this in your inputs: form.user.name and when you submit to your handler method that now looks like this:
#RequestMapping
public String save(HttpServletRequest req,
#ModelAttribute("userEditForm") UserEditFormWrapper formWrapper,
BindingResult formBindingResult,
ModelMap model,
#ModelAttribute("session") AdminSession session) {
UserEditForm form = formWrapper.getForm();
// some validation etc
}
the binding won't be triggered since AdminSession does not have a form property.
That's one way to solve this but it's kind of a hack. You don't want to have the request parameters bound to AdminSession but that's part of your model so you must have created it somewhere and placed it on the model, right? If so, then remove it from the method's parameters and just get it from the model, something like:
#RequestMapping(value = "/test", method = { RequestMethod.POST })
public String handlePost(HttpServletRequest req,
#ModelAttribute("userEditForm") UserEditForm form,
BindingResult formBindingResult, ModelMap model) {
AdminSession session = (AdminSession) model.get("session");
// some validation etc
}
I am writing a wizard-like controller that handles the management of a single bean across multiple views. I use #SessionAttributes to store the bean, and SessionStatus.setComplete() to terminate the session in the final call. However, if the user abandons the wizard and goes to another part of the application, I need to force Spring to re-create the #ModelAttribute when they return. For example:
#Controller
#SessionAttributes("commandBean")
#RequestMapping(value = "/order")
public class OrderController
{
#RequestMapping("/*", method=RequestMethod.GET)
public String getCustomerForm(#ModelAttribute("commandBean") Order commandBean)
{
return "customerForm";
}
#RequestMapping("/*", method=RequestMethod.GET)
public String saveCustomer(#ModelAttribute("commandBean") Order commandBean, BindingResult result)
{
[ Save the customer data ];
return "redirect:payment";
}
#RequestMapping("/payment", method=RequestMethod.GET)
public String getPaymentForm(#ModelAttribute("commandBean") Order commandBean)
{
return "paymentForm";
}
#RequestMapping("/payment", method=RequestMethod.GET)
public String savePayment(#ModelAttribute("commandBean") Order commandBean, BindingResult result)
{
[ Save the payment data ];
return "redirect:confirmation";
}
#RequestMapping("/confirmation", method=RequestMethod.GET)
public String getConfirmationForm(#ModelAttribute("commandBean") Order commandBean)
{
return "confirmationForm";
}
#RequestMapping("/confirmation", method=RequestMethod.GET)
public String saveOrder(#ModelAttribute("commandBean") Order commandBean, BindingResult result, SessionStatus status)
{
[ Save the payment data ];
status.setComplete();
return "redirect:/order";
}
#ModelAttribute("commandBean")
public Order getOrder()
{
return new Order();
}
}
If a user makes a request to the application that would trigger the "getCustomerForm" method (i.e., http://mysite.com/order), and there's already a "commandBean" session attribute, then "getOrder" is not called. I need to make sure that a new Order object is created in this circumstance. Do I just have to repopulate it manually in getCustomerForm?
Thoughts? Please let me know if I'm not making myself clear.
Yes, sounds like you may have to repopulate it manually in getCustomerForm - if an attribute is part of the #SessionAttributes and present in the session, then like you said #ModelAttribute method is not called on it.
An alternative may be to define a new controller with only getCustomerForm method along with the #ModelAttribute method but without the #SessionAttributes on the type so that you can guarantee that #ModelAttribute method is called, and then continue with the existing #RequestMapped methods in the existing controller.