I have a restful class to send JSON string to POST request. Data are store in DB with UTF-8 format. But the non-english characters always display as '??????', it all works fine if I get records form #Model.
Here is the code snap of rest (Using simple JSON to encoding JSON string):
#POST
#Path("/holidaylist")
#Produces(MediaType.APPLICATION_JSON)
public String getHoliday(){
List list = new LinkedList();
// Get list of holidays
List<Holiday> holidays = em.createQuery("SELECT holiday FROM Holiday holiday").getResultList();
Map event;
for(Holiday holiday : holidays){
System.out.println("======== Holiday nameļ¼ " + holiday.getHolidayName());
event = new HashMap();
event.put("id", holiday.getHolidayId());
event.put("title", holiday.getHolidayName());
event.put("start", holiday.getStartDate().toString());
list.add(event);
}
return JSONValue.toJSONString(list);
}
Thanks in advanced.
You need to make sure that you properly handle data encoding all along, starting from the DB and to the front-end. I'm not totally familiar with the SimpleJSON api, but are sure the toJSONString uses UTF-8 encoding? Also, make sure your page where you render t
Solved by using JAXB implementation. Seems simple JSON encoding issue.
Thanks everyone.
Related
I need some help please...
I am working with a GWT enabled web application. I am using the gwt-2.3.0 SDK.
I have a method that extends the DataSource class and uses the transformResponse method:
public class DeathRecordXmlDS extends DataSource {
protected void transformResponse(DSResponse response, DSRequest request, Object data){
super.transformResponse(response, request, data);
}
}
As I understand, the transformResponse() method should get control and at this point, I will have access to the data that is being provided to the Client side of my application. I am trying to work with the Object data parameter (the third parameter) that is passed in.
I am expecting an XML formatted string to be passed in. The XML will contain data (a count field) that I need to access and use.
I don't seem to be getting an XML string. Here's what I know...
I do see the XML data being passed to my webapp (the client). I can see this because I inspect the webpage that I am working with and I see the Response data. Here's an example of something that I expect to receive:
XML data from Query:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Collection numRecords="0">
<DeathRecords/>
</Collection>
The above XML is valid (I checked it in a Validator). This is a case where there was no data (No Death Records) being returned to my application. The numRecords XML attribute is set to "0". Of course, If I do have records returned the numRecords will contain the number of records and I'll get that same number of DeathRecord nodes.
I am not getting the above data (or, I don't know how to work with it) in the transformResponse() method.
Here's what I've done to try to figure this out...
The Object data parameter... it is a JavaScriptObject. I know this because I did a .getClass().getName() on it:
DeathRecordXmlDS::transformResponse() data.getClass().getName(): com.google.gwt.core.client.JavaScriptObject$
Then, to try to work with it, I converted it to a String:
com.google.gwt.core.client.JavaScriptObject dataJS = (com.google.gwt.core.client.JavaScriptObject)data;
System.out.println("DeathRecordXmlDS::transformResponse() data as a JavaScriptObject: "+dataJS.toString());
The contents of 'data' formatted as a String look like:
DeathRecordXmlDS::transformResponse() data as a JavaScriptObject: [XMLDoc <Collection>]
So, it looks like I have something that has to do with my 'Collection' node, but not a String of XML data that I can parse and get to my numRecords attribute.
What do I need to do to gain access to the XML in the transformResponse() method?
Thanks!
I think your data object is already translated to a javascript collection.
Maybe you could use the utility class XMLTools to retrieve your numRecords information:
Integer numRecords = Integer.parseInt(XMLTools.selectString(data, "Collection/#numRecords"));
After working on this for an additional period of time I was able to read the XML data that I am working with. I used the following piece of code:
try{
JsArray<JavaScriptObject> nodes = ((JavaScriptObject) XMLTools.selectNodes(data, "/Collection/#numRecords")).cast();
for (int i = 0; i < nodes.length(); i++) {
com.google.gwt.dom.client.Element element = (com.google.gwt.dom.client.Element) nodes.get(i);
numRecords = element.getNodeValue();
}
} catch(Exception e){
// If Parsing fails, capture the exception
System.out.println("DeathRecordXmlDS::transformResponse() Not able to parse the XML");
}
I think the first step to solving this was understanding that the parameter 'data' of type Object was really a JavaScriptObject. I learned this after looking at the .getClass() and .getName(). This helped me understand what I was working with:
System.out.println("DeathRecordXmlDS::transformResponse() data.getClass().getName(): "+data.getClass().getName());
Once I knew it was a JavaScriptObject, I was able to do a little more focused of a Google search for what I was trying to accomplish. I was a little surprised that the XMLTools.selectNodes() function worked the way it did, but the end result is that I was able to read the numRecords attribute.
Thanks for the suggestion!
I am building a REST API and facing this issue: How can REST API pass very large JSON?
Basically, I want to connect to Database and return the training data. The problem is in Database I have 400,000 data. If I wrap them into a JSON file and pass through GET method, the server would throw Heap overflow exception.
What methods we can use to solve this problem?
DBTraining trainingdata = new DBTraining();
#GET
#Produces("application/json")
#Path("/{cat_id}")
public Response getAllDataById(#PathParam("cat_id") String cat_id) {
List<TrainingData> list = new ArrayList<TrainingData>();
try {
list = trainingdata.getAllDataById(cat_id);
Gson gson = new Gson();
Type dataListType = new TypeToken<List<TrainingData>>() {
}.getType();
String jsonString = gson.toJson(list, dataListType);
return Response.ok().entity(jsonString).header("Access-Control-Allow-Origin", "*").header("Access-Control-Allow-Methods", "GET").build();
} catch (SQLException e) {
logger.warn(e.getMessage());
}
return null;
}
The RESTful way of doing this is to create a paginated API. First, add query parameters to set page size, page number, and maximum number of items per page. Use sensible defaults if any of these are not provided or unrealistic values are provided. Second, modify the database query to retrieve only a subset of the data. Convert that to JSON and use that as the payload of your response. Finally, in following HATEOAS principles, provide links to the next page (provided you're not on the last page) and previous page (provided you're not on the first page). For bonus points, provide links to the first page and last page as well.
By designing your endpoint this way, you get very consistent performance characteristics and can handle data sets that continue to grow.
The GitHub API provides a good example of this.
My suggestion is no to pass the data as a JSON but as a file using multipart/form-data. In your file, each line could be a JSON representing a data record. Then, it would be easy to use a FileOutputStream to receive te file. Then, you can process the file line by line to avoid memory problems.
A Grails example:
if(params.myFile){
if(params.myFile instanceof org.springframework.web.multipart.commons.CommonsMultipartFile){
def fileName = "/tmp/myReceivedFile.txt"
new FileOutputStream(fileName).leftShift(params.myFile.getInputStream())
}
else
//print or signal error
}
You can use curl to pass your file:
curl -F "myFile=#/mySendigFile.txt" http://acme.com/my-service
More details on a similar solution on https://stackoverflow.com/a/13076550/2476435
HTTP has the notion of chunked encoding that allows you send a HTTP response body in smaller pieces to prevent the server from having to hold the entire response in memory. You need to find out how your server framework supports chunked encoding.
I have an XPages page which contains the REST service component. I'm using the "documentJsonService".
Awesome component and everything else is working fine, but I'm having issues with the date formats and don't know what to do.
The Notes Document where I'm reading the data from, contains a DateTime item having a proper date e.g. 01.09.2014 (finnish format: dd.MM.yyyy). The REST component returns the date in "2014-09-01" (string). This is fine. However when I do a HTTP POST to the server with the same exact data, Domino changes the "2014-09-01" string date into 09.01.2014 Notes Date time item.
Don't know any more what to do. Why Domino gives date in format A and when I give it back in same format, something strange happens.
This same happens on Linux and Windows environments.
Domino version is 9.0.1.
Thanks already. I'm more or less lost with this "feature" :)
I would say: broken as designed. To my knowledge the JSON format returned is always in the form yyyy-mm-dd, while the format expected when posting depends on the browser locale. You would need to "hack around it".
I'm not a big fan of the ready baked JSON services, I'd rather roll my own, where I can be very specific with the formats and (more importantly) add validation before I write data back. You can find a sample on my blog
Basically you implement a bean like this:
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.ibm.domino.services.ServiceException;
import com.ibm.domino.services.rest.RestServiceEngine;
import com.ibm.xsp.extlib.component.rest.CustomService;
import com.ibm.xsp.extlib.component.rest.CustomServiceBean;
public class CustomSearchHelper extends CustomServiceBean {
#Override
public void renderService(CustomService service, RestServiceEngine engine) throws ServiceException {
HttpServletRequest request = engine.getHttpRequest();
HttpServletResponse response = engine.getHttpResponse();
response.setHeader("Content-Type", "application/json; charset=UTF-8");
// Your code goes here!
}
}
you need to check in the request what method GET or POST was used, but then it is easy to continue. While you are on it: the OpenNTF Domino API makes your life much easier.
I'm using the Dojo datagrid client side, it works well and according to documentation it generates the following GET request when clicking on the column header:
GET http://localhost:8080/books/rest/books?sort(+isbn)
Problem is that I can't interpret the query parameter "sort(+isbn)" on the server side using the Apache Wink framework, because there's no value set for it. E.g. I'd expect something like "sort=+isbn" instead.
Here's my server side code:
#Path("/books")
public class BookServiceImpl implements BookService {
...
#GET
#Produces(MediaType.APPLICATION_JSON)
public String getBook(#QueryParam("sort") String sortBy) {
System.out.println("Received Queryparam for sort is " + sortBy);
return "";
}
}
Since "sort(+isbn)" has no value assigned to it, it appears to be an invalid query parameter. Not sure why Dojo datagrid uses this convention.
Would appreciate help as to how to work around this on the Java side, ideally using Wink or another mechanism to process GET requests.
Try to use #Context UriInfo to get the full uri info, call to UriInfo.getQueryParameters to get all query params. I believe sort(+isbn) will be there.
I'm using jqGrid to display some data to the user. One of the features needed is for users to be able to search the grid. I'm using a WCF Data Service to get this data and return it.
When I first started jqGrid development I just needed pagination (no searching required) and was successfully able to use the following method:
[WebGet(ResponseFormat = WebMessageFormat.Json)]
public String GetStuff(int? page, int? rows)
{
// pagination going on in here
}
Then I needed the search so I added a param of type string like so:
[WebGet(ResponseFormat = WebMessageFormat.Json)]
public String GetStuff(int? page, int? rows, string search)
{
// more stuff going on in here
}
and then I get a 400 Bad Request error. I assume its because of the search param, I just don't understand why int works (and even bool worked) but string doesn't. Does it have anything to do with the fact that WCF Data Services are RESTful?
I of course double-checked the query string that jqGrid sends (via ajax) and it matches the param name. There are some extra query string params that jqGrid sends that are not used (ignoring them worked fine with my original pagination code)
String literals in the query URL must be quoted with single quotes. So the above service operation would be called like this:
/GetStuff?page=1&rows=10&search='John'
Does your query string look like that?