I'm trying to convert a struts 1 application to Spring MVC 3.0. We have an form with quite a few parameters, most of which where automatically binded in struts. However there where a number of fields in the format fieldName_# where # is a number that we manually bound by looping through the request.
I'm looking for a tidier way to do this in Spring mvc, but don't know where to start.
Ideally we should have them as fieldName[#] and it would be easier, but we cannot change this and have to keep the fieldName_# format. Also the number of these fields that are sent in the request are unknown.
One way to achieve this is by wrapping the servletRequest and implementing the getParameter (and associated methods) such a way that parameters with name fieldName_# are returned as fieldName[#]. A servletFilter would be one option to wrap the request.
Related
I am using Jersey to implement rest api and Jackson to provide JSON support. I am trying to remove certain properties before serialization by overriding BeanSerializerModifier.changeProperties method.
But removing properties will be based on query parameter. Is there any way to access the query parameter in my implementation?
Use of BeanSerializerModifier itself would get complicated as the method is only called once when construction necessarily JsonSerializer for the first time. As to passing query parameters, you could pass them using contextual attributes and ObjectWriter (constructed from ObjectMapper), but that means taking over quite a bit of serialization automation from Jersey.
There is one mechanism that could be helpful in modifying serialization aspects without taking over the whole process: registering ObjectWriterModifier, using ObjectWriterInjector. These are part of Jackson JAX-RS provider, added in Jackson 2.3. Without knowing more details I don't know how easy this would be; part of the issue is that query parameters are more of an input side things, so there is no direct access to them from output processing side.
Is there an easy way to pack multiple parameters from the URL into a single unit and send it to a Spring MVC Controller?
I have more than 20 parameters and it is inconvenient to type #RequestParam for each of them.
Also, how we can I handle a varying number of parameters, e.g if I have some list of info that varies in size?
This is what Spring's MVC's #ModelAttribute annotation is used for. You can place all your parameters on a bean and move that around instead.
When you submit your form, Spring binds the request parameters into your bean and it works also with list parameters.
I use Jersey framework to communicate (marshalling and unmarshalling object and xml) with REST api. I send data (object has lot attributes) this way:
.
.
ClientResponse response = webResource.type("application/xml").post(ClientResponse.class, object);
.
I would like to ask how can I validate some object attributes (for example private String code in Object should be in format of two numbers etc.)
aYou mean in the service that receives the object? How have you tried? It comes in as an object, or whatever you want it to come in as. We frequently take in Map<String,Object> and then do validation on that map (if we need to decide what subtype to create from the post for example). If you have Jersey unmarshall your request into the POJO for you, you can then do whatever validation you want and return a Response object with the validation error information to your client if the object doesn't pass.
So in other words, the validation is up to you. There are a few validation frameworks out there that you could try to help, such as javax.validation but IMHO it's usually easier to just test each property you need to validate yourself using conditionals, regexps, whatever.
In my opinion the validation comes with a webframework like struts, wicked, jfc... to name some. There the user inputs his data in a form to create the object he wants to post to a service. The webframeworks already got components to validate this data. When there was a positive validation you make the post call to your service.
I'm wanting to to add an endpoint like /user/foo where foo is one of a set of values determined at runtime. I'm wondering what the best way is to do this in Spring, or indeed if it should even been done in Spring an not handled at the controller level.
I'm currently using Springs security filter chain, so I did think about putting a filter in front of /user/* to do this validation. Is this a reasonable solution or is there a more desirable solution I have missed?
You can use #PathVariable annotation on a method argument. #PathVariable also allows regex if you need to validate the structure of the varible.
http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/mvc.html#mvc-ann-requestmapping
http://static.springsource.org/spring/docs/3.0.x/javadoc-api/org/springframework/web/bind/annotation/PathVariable.html
and for the regex
http://static.springsource.org/spring/docs/3.0.x/javadoc-api/org/springframework/web/bind/annotation/RequestMapping.html
I found that, by default when I using Spring MVC, "2010/01/02" binds correctly, but "2010-01-02" does not.
I know Spring has some useful binding mechanisms like initBinder. However, in this question I want to know where is the rule defined. Does anyone know that for example RFC documents of HTTP or Spring references.
It's just coincidence.
Spring MVC can implicitly convert input parameters to model objects via their single-argument constructor that takes String (if model objects have such constructors). Date has this constructor, though it's deprecated, so that this behaviour is determined by behaviour of that constructor.