Java noob here. I'm trying to develop a web service as per the following diagram.
When a POST request is sent to the REST server, with certain values, the values (being read from a list, in a loop) get inserted in a table (new row with an id). Server returns HTTP 202 Accepted.
To ensure that the resource(with id from 1) is created, a GET request is issued that returns the POJO as Json.
Finally a PATCH request is sent to update a certain column.
I have written a service class that does all three tasks when each API is called individually. I need to implement something that would automatically execute steps 2 and 3 when a POST request is sent to the server. Here's my code so far.
#Path("attachments")
public class FilesService {
private TiedostoService tiedostoService;
private AttachmentService attachmentService;
#GET
#Path("{id}")
#Produces({MediaType.APPLICATION_JSON})
public Response listAttachmentsAsJson(#PathParam("id") Integer attachmentId) throws Exception {
attachmentService = new AttachmentService();
Gson gson = new GsonBuilder().excludeFieldsWithoutExposeAnnotation().create();
Attachment attachment = attachmentService.getAttachment(attachmentId);
String jsonString = gson.toJson(attachment.toString());
return Response.status(Response.Status.OK).entity(jsonString).build();
}
#PATCH
#Path("{id}")
#Produces({MediaType.APPLICATION_JSON})
public Response patchAttachments(#PathParam("id") Integer attachmentId) throws Exception {
attachmentService = new AttachmentService();
Integer update = attachmentService.update(attachmentId);
String jsonString = new Gson().toJson(update);
return Response.status(Response.Status.ACCEPTED).entity(jsonString).build();
}
#POST
#Produces({MediaType.APPLICATION_JSON})
public Response migrateToMinio(#Context UriInfo uriInfo) throws Exception {
Response response;
List<String> responseList = new ArrayList<>();
tiedostoService = new TiedostoService();
attachmentService = new AttachmentService();
List<Tiedosto> tiedostoList = tiedostoService.getAllFiles();
String responseString = null;
int i = 1;
for (Tiedosto tiedosto : tiedostoList) {
Attachment attachment = new Attachment();
attachment.setCustomerId(tiedosto.getCustomerId());
attachment.setSize(tiedosto.getFileSize());
Integer id = attachmentService.createNew(attachment);
if (id == 1) {
UriBuilder builder = uriInfo.getAbsolutePathBuilder();
builder.path(Integer.toString(i));
response = Response.created(builder.build()).build();
System.out.println(response);
responseString = response.toString();
}
responseList.add(responseString);
i++;
}
String jsonString = new Gson().toJson(responseList);
return Response.status(Response.Status.OK).entity(jsonString).build();
}
}
when I test the individual endpoints with curl or postman, they work as expected, but I got stuck on how to execute GET and PATCH automatically after POST. I'd really appreciate some advice/suggestions/help.
We have created the Jersy REST service.
We are returning response object with 10 String fields and one Hash Map in format specified in below code snippet.
We could receive all the 10 string field values.
We can also see the HashMap with key/values when access it from client program.
CustomObject in HashMap became String when access it from client program.
so it throws exception
Listcom.tetherfi.restful.model.AppTypeData#2dc0f069
Test
err: java.lang.ClassCastException: java.lang.String cannot be cast to com.tetherfi.restful.model.AppTypeData.
We use Moxy to do the mapping. Please advise whether there is a way to retain the object value.
Response object from Jersy service
#XmlRootElement
public class ServiceRespParams {
private String param1;
private String param2;
private String param3;
private String param4;
private String param5;
private HashMap<String,ArrayList<AppTypeData>>hm;
public HashMap<String, ArrayList<AppTypeData>> getHm() {
return hm;
}
public void setHm(HashMap<String, ArrayList<AppTypeData>> hm) {
this.hm = hm;
}
Client code
public class Client {
public ServiceResponse postRequest(ServiceRequest request) {
Logger logger = Logger.getLogger("JerseyClient");
ServiceResponse serviceResponse = null;
WebTarget webTarget = null;
Response response = null;
// creating client with MOXy JSON
Client client = ClientBuilder.newClient();
try {
String url = "http://localhost:9080/Rest_ProxyLayer/webapi/doc01";
logger.info("Sending Request.... "+url);
webTarget = client.target(url).property(ClientProperties.CONNECT_TIMEOUT, 1000)
.property(ClientProperties.READ_TIMEOUT, 1000);
logger.info("Request Sent...");
Invocation.Builder invocationBuilder = webTarget.request(MediaType.APPLICATION_JSON);
response = invocationBuilder.get();
logger.info("Response Status :"+response.getStatus());
serviceResponse = response.readEntity(ServiceResponse.class);
System.out.println("Response from service"+ serviceResponse.getHm().get("CreditCard").get(0).getParam1());
} catch (Exception e) {
logger.error("Error!! Check connection..", e);
e.printStackTrace();
}
return serviceResponse;
}
}
It throws class cast exception when try to access the method.
System.out.println("Response from service"+ serviceResponse.getHm().get("CreditCard").get(0).getParam1());
Output from Rest service. Hashmap entries are below. It shows object but it seems to be converted to string.
HM: {CreditCard=[com.tetherfi.restful.model.AppTypeData#1b6c278e, com.tetherfi.restful.model.AppTypeData#208f5a00]}
Thanks
Vinoth
I have to implement some JUnit tests for my rest services.
For instance this is one of my Rest services:
#Path("/dni-fe")
public class HelloWorld
{
#POST
#Path("/home")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public MachineResponse doMachineRegister(MachineBean machineBean)
{
MachineResponse response = new MachineResponse();
String name = machineBean.getName();
String country = machineBean.getCountry();
String company = machineBean.getCompany();
String model = machineBean.getModel();
//make some stuff and some queries on db to populate the response object
return response;
}
And here is my test on this service:
public class MachineResponseTest {
private static final String BASE_URI = "http://localhost:8080/dni-fe/home"
#Test
public void testDevice() {
WebResource resource = Client.create().resource(BASE_URI);
resource.accept(MediaType.APPLICATION_JSON);
StringBuilder sb = new StringBuilder();
sb.append("{\"name\":\"123456\",\n");
sb.append(" \"country\":\"Spain\",\n");
sb.append(" \"company\":\"xxx\",\n");
sb.append(" \"model\":\"1.10.0\"\n}");
MachineResponse result = resource.post(MachineResponse.class,sb.toString());
}
The test fails with the following error:
com.sun.jersey.api.client.UniformInterfaceException: POST
http://localhost:8080/dni-fe/home returned a response status of 415
Unsupported Media Type at
com.sun.jersey.api.client.WebResource.handle(WebResource.java:686)
I am fairly sure you have to use .type(MediaType.APPLICATION_JSON), not .accept(
You can use simple JSONObject from org.json.JSONObject and pass data as toString of it. Sample code is
JSONObject address = new JSONObject();
address.put("line1", address1);
address.put("line2", address2);
address.put("city", city);
address.put("state", state);
address.put("postalCode", zip);
address.put("country", "US");
address.toString()
I am using RestFul Webservice with JBoss Server to deploy the app to receive the JSONObject to my web service ,to test that i have created the web service and written test cases for it .Now i got hung up in passing the JSONobject from test case to web services , when i pass the json object to #post service calls it responses that Null Pointer Exception , even i have tried with passing string to it it responds null values.
I have used Annotations as follows in webservice
#consumes({Mediatype.APPLICATION_JSON})
#Consumes("application/json")
Test case As:
#Test
public void testgetmsg() {
String msg = "{\"patient\":[{\"id\":\"6\",\"title\":\"Test\"}]}";
try {
JSONObject obj = new JSONObject(new JSONTokener(msg));
WebResource resource = client.resource( "https://localhost:8443/../../resources/create");
ClientResponse response = resource.type(MediaType.APPLICATION_JSON).accept(MediaType.APPLICATION_JSON).
entity(obj).post(ClientResponse.class,JSONObject.class);
}
}
can any body guide me to proceed further ?
Thanks in Advance
You don't need to create the json object, you can just pass the string.
you should
ClientResponse response = resource.type(MediaType.APPLICATION_JSON)
.accept(MediaType.APPLICATION_JSON)
.post(ClientResponse.class, msg);
//CLIENT
public static void createStudent() {
String input = "{\"id\":12,\"firstName\":\"Fade To Black\",\"lastName\":\"Joy\"}";
ClientResponse response = service.path("class/post")
.type("application/json").post(ClientResponse.class, input);
System.out.println("Output from Server .... \n");
String output = response.getEntity(String.class);
System.out.println(output);
System.out.println(response.getStatus()+ "OK");
}
Instead of using code client you can use add on firefox (POSTER) to passing value as json or formparam...
// create new student SERVER
//class
#POST
#Path("post")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public Response createStudent(Student st) {
// add new student
StudentDAO.instance.getModelStudent().put("8", st);
// response status code
return Response.status(200).entity(st).build();
}
I have a method;
#POST
#Path("test")
#Consumes(MediaType.APPLICATION_JSON)
public void test(ObjectOne objectOne, ObjectTwo objectTwo)
Now I know I can post a single object in json format, just putting it into the body.
But is it possible to do multiple objects? If so, how?
You can not use your method like this as correctly stated by Tarlog.
However, you can do this:
#POST
#Path("test")
#Consumes(MediaType.APPLICATION_JSON)
public void test(List<ObjectOne> objects)
or this:
#POST
#Path("test")
#Consumes(MediaType.APPLICATION_JSON)
public void test(BeanWithObjectOneAndObjectTwo containerObject)
Furthermore, you can always combine your method with GET parameters:
#POST
#Path("test")
#Consumes(MediaType.APPLICATION_JSON)
public void test(List<ObjectOne> objects, #QueryParam("objectTwoId") long objectTwoId)
The answer is no.
The reason is simple: This about the parameters you can receive in a method. They must be related to the request. Right? So they must be either headers or cookies or query parameters or matrix parameters or path parameters or request body. (Just to tell the complete story there is additional types of parameters called context).
Now, when you receive JSON object in your request, you receive it in a request body. How many bodies the request may have? One and only one. So you can receive only one JSON object.
If we look at what the OP is trying to do, he/she is trying to post two (possibly unrelated) JSON objects. First any solution to try and send one part as the body, and one part as some other param, IMO, are horrible solutions. POST data should go in the body. It's not right to do something just because it works. Some work-arounds might be violating basic REST principles.
I see a few solutions
Use application/x-www-form-urlencoded
Use Multipart
Just wrap them in a single parent object
1. Use application/x-www-form-urlencoded
Another option is to just use application/x-www-form-urlencoded. We can actually have JSON values. For examle
curl -v http://localhost:8080/api/model \
-d 'one={"modelOne":"helloone"}' \
-d 'two={"modelTwo":"hellotwo"}'
public class ModelOne {
public String modelOne;
}
public class ModelTwo {
public String modelTwo;
}
#Path("model")
public class ModelResource {
#POST
#Consumes(MediaType.APPLICATION_FORM_URLENCODED)
public String post(#FormParam("one") ModelOne modelOne,
#FormParam("two") ModelTwo modelTwo) {
return modelOne.modelOne + ":" + modelTwo.modelTwo;
}
}
The one thing we need to get this to work is a ParamConverterProvider to get this to work. Below is one that has been implemented by Michal Gadjos of the Jersey Team (found here with explanation).
#Provider
public class JacksonJsonParamConverterProvider implements ParamConverterProvider {
#Context
private Providers providers;
#Override
public <T> ParamConverter<T> getConverter(final Class<T> rawType,
final Type genericType,
final Annotation[] annotations) {
// Check whether we can convert the given type with Jackson.
final MessageBodyReader<T> mbr = providers.getMessageBodyReader(rawType,
genericType, annotations, MediaType.APPLICATION_JSON_TYPE);
if (mbr == null
|| !mbr.isReadable(rawType, genericType, annotations, MediaType.APPLICATION_JSON_TYPE)) {
return null;
}
// Obtain custom ObjectMapper for special handling.
final ContextResolver<ObjectMapper> contextResolver = providers
.getContextResolver(ObjectMapper.class, MediaType.APPLICATION_JSON_TYPE);
final ObjectMapper mapper = contextResolver != null ?
contextResolver.getContext(rawType) : new ObjectMapper();
// Create ParamConverter.
return new ParamConverter<T>() {
#Override
public T fromString(final String value) {
try {
return mapper.reader(rawType).readValue(value);
} catch (IOException e) {
throw new ProcessingException(e);
}
}
#Override
public String toString(final T value) {
try {
return mapper.writer().writeValueAsString(value);
} catch (JsonProcessingException e) {
throw new ProcessingException(e);
}
}
};
}
}
If you aren't scanning for resource and providers, just register this provider, and the above example should work.
2. Use Multipart
One solution that no one has mentioned, is to use multipart. This allows us to send arbitrary parts in a request. Since each request can only have one entity body, multipart is the work around, as it allows to have different parts (with their own content types) as part of the entity body.
Here is an example using Jersey (see official doc here)
Dependency
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-multipart</artifactId>
<version>${jersey-2.x.version}</version>
</dependency>
Register the MultipartFeature
import javax.ws.rs.ApplicationPath;
import org.glassfish.jersey.media.multipart.MultiPartFeature;
import org.glassfish.jersey.server.ResourceConfig;
#ApplicationPath("/api")
public class JerseyApplication extends ResourceConfig {
public JerseyApplication() {
packages("stackoverflow.jersey");
register(MultiPartFeature.class);
}
}
Resource class
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import org.glassfish.jersey.media.multipart.FormDataParam;
#Path("foobar")
public class MultipartResource {
#POST
#Consumes(MediaType.MULTIPART_FORM_DATA)
public Response postFooBar(#FormDataParam("foo") Foo foo,
#FormDataParam("bar") Bar bar) {
String response = foo.foo + "; " + bar.bar;
return Response.ok(response).build();
}
public static class Foo {
public String foo;
}
public static class Bar {
public String bar;
}
}
Now the tricky part with some clients is that there isn't a way to set the Content-Type of each body part, which is required for the above to work. The multipart provider will look up message body reader, based on the type of each part. If it's not set to application/json or a type, the Foo or Bar has a reader for, this will fail. We will use JSON here. There's no extra configuration but to have a reader available. I'll use Jackson. With the below dependency, no other configuration should be required, as the provider will be discovered through classpath scanning.
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-jackson</artifactId>
<version>${jersey-2.x.version}</version>
</dependency>
Now the test. I will be using cURL. You can see I explicitly set the Content-Type for each part with type. The -F signifies to different part. (See very bottom of the post for an idea of how the request body actually looks.)
curl -v -X POST \
-H "Content-Type:multipart/form-data" \
-F "bar={\"bar\":\"BarBar\"};type=application/json" \
-F "foo={\"foo\":\"FooFoo\"};type=application/json" \
http://localhost:8080/api/foobar
Result: FooFoo; BarBar
The result is exactly as we expected. If you look at the resource method, all we do is return this string foo.foo + "; " + bar.bar, gathered from the two JSON objects.
You can see some examples using some different JAX-RS clients, in the links below. You will also see some server side example also from those different JAX-RS implementations. Each link should have somewhere in it a link to the official documentation for that implementation
Jersey example
Resteasy example
CXF example
There are other JAX-RS implementations out there, but you will need to find the documentation for it yourself. The above three are the only ones I have experience with.
As far as Javascript clients, most of the example I see (e.g. some of these involve setting the Content-Type to undefined/false (using FormData), letting the Browser handle the it. But this will not work for us, as the Browser will not set the Content-Type for each part. And the default type is text/plain.
I'm sure there are libraries out there that allow setting the type for each part, but just to show you how it can be done manually, I'll post an example (got a little help from here. I'll be using Angular, but the grunt work of building the entity body will be plain old Javascript.
<!DOCTYPE html>
<html ng-app="multipartApp">
<head>
<script src="js/libs/angular.js/angular.js"></script>
<script>
angular.module("multipartApp", [])
.controller("defaultCtrl", function($scope, $http) {
$scope.sendData = function() {
var foo = JSON.stringify({foo: "FooFoo"});
var bar = JSON.stringify({bar: "BarBar"});
var boundary = Math.random().toString().substr(2);
var header = "multipart/form-data; charset=utf-8; boundary=" + boundary;
$http({
url: "/api/foobar",
headers: { "Content-Type": header },
data: createRequest(foo, bar, boundary),
method: "POST"
}).then(function(response) {
$scope.result = response.data;
});
};
function createRequest(foo, bar, boundary) {
var multipart = "";
multipart += "--" + boundary
+ "\r\nContent-Disposition: form-data; name=foo"
+ "\r\nContent-type: application/json"
+ "\r\n\r\n" + foo + "\r\n";
multipart += "--" + boundary
+ "\r\nContent-Disposition: form-data; name=bar"
+ "\r\nContent-type: application/json"
+ "\r\n\r\n" + bar + "\r\n";
multipart += "--" + boundary + "--\r\n";
return multipart;
}
});
</script>
</head>
<body>
<div ng-controller="defaultCtrl">
<button ng-click="sendData()">Send</button>
<p>{{result}}</p>
</div>
</body>
</html>
The interesting part is the createRequest function. This is where we build the multipart, setting the Content-Type of each part to application/json, and concatenating the stringified foo and bar objects to each part. If you are unfamiliar multipart format see here for more info. The other interesting part is the header. We set it to multipart/form-data.
Below is the result. In Angular I just used the result to show in the HTML, with $scope.result = response.data. The button you see was just to make the request. You will also see the request data in firebug
3. Just wrap them in a single parent object
This option should be self explanatory, as others have already mentioned.
The next approach is usually applied in this kind of cases:
TransferObject {
ObjectOne objectOne;
ObjectTwo objectTwo;
//getters/setters
}
#POST
#Path("test")
#Consumes(MediaType.APPLICATION_JSON)
public void test(TransferObject object){
// object.getObejctOne()....
}
You can't put two separate objects in one single POST call as explained by Tarlog.
Anyway you could create a third container object that contains the first two objects and pass that one within the POS call.
I have also faced with these problem. Maybe this will help.
#POST
#Path("/{par}")
#Produces(MediaType.APPLICATION_JSON)
#Consumes(MediaType.APPLICATION_JSON)
public Object centralService(#PathParam("par") String operation, Object requestEntity) throws JSONException {
ObjectMapper objectMapper=new ObjectMapper();
Cars cars = new Cars();
Seller seller = new Seller();
String someThingElse;
HashMap<String, Object> mapper = new HashMap<>(); //Diamond )))
mapper = (HashMap<String, Object>) requestEntity;
cars=objectMapper.convertValue(mapper.get("cars"), Cars.class);
seller=objectMapper.convertValue(mapper.get("seller"), Seller.class);
someThingElse=objectMapper.convertValue(mapper.get("someThingElse"), String.class);
System.out.println("Cars Data "+cars.toString());
System.out.println("Sellers Data "+seller.toString());
System.out.println("SomeThingElse "+someThingElse);
if (operation.equals("search")) {
System.out.println("Searching");
} else if (operation.equals("insertNewData")) {
System.out.println("Inserting New Data");
} else if (operation.equals("buyCar")) {
System.out.println("Buying new Car");
}
JSONObject json=new JSONObject();
json.put("result","Works Fine!!!");
return json.toString();
}
*******CARS POJO********#XmlRootElement for Mapping Object to XML or JSON***
#XmlRootElement
public class Cars {
private int id;
private String brand;
private String model;
private String body_type;
private String fuel;
private String engine_volume;
private String horsepower;
private String transmission;
private String drive;
private String status;
private String mileage;
private String price;
private String description;
private String picture;
private String fk_seller_oid;
} // Setters and Getters Omitted
*******SELLER POJO********#XmlRootElement for Mapping Object to XML or JSON***
#XmlRootElement
public class Seller {
private int id;
private String name;
private String surname;
private String phone;
private String email;
private String country;
private String city;
private String paste_date;
}//Setters and Getters omitted too
*********************FRONT END Looks Like This******************
$(function(){
$('#post').on('click',function(){
console.log('Begins');
$.ajax({
type:'POST',
url: '/ENGINE/cars/test',
contentType: "application/json; charset=utf-8",
dataType: "json",
data:complexObject(),
success: function(data){
console.log('Sended and returned'+JSON.stringify(data));
},
error: function(err){
console.log('Error');
console.log("AJAX error in request: " + JSON.stringify(err, null, 2));
}
}); //-- END of Ajax
console.log('Ends POST');
console.log(formToJSON());
}); // -- END of click function POST
function complexObject(){
return JSON.stringify({
"cars":{"id":"1234","brand":"Mercedes","model":"S class","body_type":"Sedan","fuel":"Benzoline","engine_volume":"6.5",
"horsepower":"1600","transmission":"Automat","drive":"Full PLag","status":"new","mileage":"7.00","price":"15000",
"description":"new car and very nice car","picture":"mercedes.jpg","fk_seller_oid":"1234444"},
"seller":{ "id":"234","name":"Djonotan","surname":"Klinton","phone":"+994707702747","email":"email#gmail.com", "country":"Azeribaijan","city":"Baku","paste_date":"20150327"},
"someThingElse":"String type of element"
});
} //-- END of Complex Object
});// -- END of JQuery - Ajax
It can be done by having the POST method declared to accept array of objects. Example like this
T[] create(#RequestBody T[] objects) {
for( T object : objects ) {
service.create(object);
}
}
Change #Consumes(MediaType.APPLICATION_JSON)
to #Consumes({MediaType.APPLICATION_FORM_URLENCODED})
Then you can putting multiple objects into the body
My solution is written for CXF, it appears to be quite simple.
import org.apache.cxf.jaxrs.ext.multipart.Multipart;
#POST
#Path("paramTest")
#Consumes(MediaType.MULTIPART_FORM_DATA)
public GenericResult paramTest(
#Multipart(value = "myData", type=MediaType.APPLICATION_JSON)
ObjectOne myData,
#Multipart(value = "infoList", type=MediaType.APPLICATION_JSON)
ObjectTwo[] infoList);
The test code for this with io.restassurred:
#Test
public void paramTest()
{
String payload1 = "" +
"{ \"name\": \"someName\", \"branch\": \"testBranch\" }";
String payload2 =
" [ { \"name\": \"cn\", \"status\": \"ts\" }," +
"{ \"name\": \"cn2\", \"status\": \"ts2\" } ] ]";
RestAssured.
given().
contentType("multipart/form-data").
multiPart("myData", payload1, "application/json").
multiPart("infoList", payload2, "application/json").
post(String.format("%s/paramTest", API_PATH)).
then().
statusCode(HttpStatus.SC_OK).
contentType(ContentType.JSON).
body("success", Matchers.equalTo(true));
}