I'm using a Jersey (v 1.17.1) client to communicate with a remote server that I don't have under my control (so I can't see the incomming requests).
I like to issue a POST request with JSON data, that has a structure similar to this example:
{"customer":"Someone",
"date":"2013-09-12",
"items":[{
"sequenceNo":1,
"name":"foo",
"quantity":2,
"price":42,
"tax":{"percent":7,"name":"vat 7%"}
},
{
"sequenceNo":2,
"name":"bar",
"quantity":5,
"price":23,
"tax":{"percent":7,"name":"vat 7%"}
}
]
}
That's my code:
final Client c = Client.create();
final WebResource service = c.resource(SERVER);
final Form form = new Form();
form.add("customer", "Someone");
form.add("date", "2013-09-12");
form.add("items", XXX); // how do I do that?
final ClientResponse response = service.path("aPath").queryParam("param", "value").cookie(new Cookie("token", token))
.type(MediaType.APPLICATION_JSON)
.post(ClientResponse.class, form);
final String raw = response.getEntity(String.class);
System.out.println("Response " + raw);
I tried several approaches (like nesting another Form object), but I always get the same result: The server returns 400 - Bad Request ("The request sent by the client was syntactically incorrect (Bad Request).") I assume because the mandatory parameter items isn't sent correctly.
Does somebody know how I nest JSON data like described? I think it is a common case, but I found no examples in the web.
Form is essentially a Map that limits your values to Strings. What you need is a simple Map (e.g. a HashMap). Every nested element will also be a map. So you will have something like this.
Map<String, Object> data = new HashMap<String, Object>();
data.put("customer", "Someone");
data.put("date", "2013-09-12");
Map<String, Object> item1 = new HashMap<String, Object>();
item1.put("sequenceNo", 2);
item1.put("name", "foo");
data.put("items", Arrays.asList(item1));
This way you can do as much nesting as you need.
Alternatively you can create a few classes that represent your data structures. Jersey will know how to serialize it.
class Item {
String name;
int sequenceNo;
// getters & setters
}
class Data {
String customer;
String date;
List<Item> items;
// getters & setters
}
Related
I am trying to get a single nested value from a ResponseEntity but I am trying to do so without having to create a pojo for every possible item as this is a third party api response.
Example response.getBody() as it appears in Postman:
{
"message": "2 records found",
"records": [
{
"Account": {
"Id": "1",
"Name": "Foo Inc"
},
"CaseNumber": "200",
"Contact": {
"FirstName": "Foo",
"LastName": "Bar"
},
"Status": "In Progress",
"StatusMessage": "We are working on this."
},
{
"Account": {
"Id": "1",
"Name": "Foo Inc"
},
"CaseNumber": "100",
"Contact": {
"FirstName": "Foo",
"LastName": "Bar"
},
"Status": "Closed"
}
]
}
Basically, if I were in JS, I am looking for:
for(let record of res.body.records){
if(record && record.CaseNumber === "200"){
console.log(record.Status)
}
res.body.records[0].Status
Currently, they are are doing this to check if the response is empty:
ResponseEntity<Object> response = restTemplate.exchange(sfdcURL, HttpMethod.POST, entity, Object.class);
LinkedHashMap<Object, Object> resMap = (LinkedHashMap<Object, Object>) response.getBody();
List<Object> recordsList = (List<Object>) resMap.get("records");
if (recordsList.size() <= 0) { return error }
But I need to get the value of of "Status" and I need to do so without creating a pojo.
I appreciate any guidance on how I can do this in Java
UPDATE
So the response.getBody() is returned and when it is displayed in Postman, it looks like the pretty JSON shown above. However, when I do:
System.out.println(response.getBody().toString())
it looks like:
{message=2 Records Found, records=[{Account={Id=1, Name=Foo Inc}, CaseNumber=200, Contact={FirstName=Foo, LastName=Bar}, //etc
To make it worse, one of the fields appears in the console as follows (including linebreaks):
[...], Status=In Progress, LastEmail=From: noreply#blah.com
Sent: 2022-08-08 10:14:54
To: foo#bar.com
Subject: apropos case #200
Hello Foo,
We are working on your case and stuff
Thank you,
us, StatusMessage=We are working on this., OtherFields=blah, [...]
text.replaceAll("=", ":") would help some, but won't add quotations marks nor would it help separate that email block.
How can I so that the responses here like ObjectMapper and JSONObject can work?
You can either convert the string to valid json (not that trivial) and deserialise into a Map<String, Object>, or just pluck the value out of the raw string using regex:
String statusOfCaseNumber200 = response.getBody().toString()
.replaceAll(".*CaseNumber=200\\b.*?\\bStatus=([^,}]*).*", "$1");
This matches the whole string, captures the desired status value then replaces with the status, effectively "extracting" it.
The regex:
.*CaseNumber=200\b everything up to and including CaseNumber=200 (not matching longer numbers like 2001)
.*? as few chars as possible
\\bStatus= "Status=" without any preceding word chars
([^,}]*) non comma/curly brace characters
.* the rest
It's not bulletproof, but it will probably work for your use case so it doesn't need to be bulletproof.
Some test code:
String body = "{message=2 Records Found, records=[{Account={Id=1, Name=Foo Inc}, CaseNumber=200, Contact={FirstName=Foo, LastName=Bar}, Status=In Progress, StatusMessage=We are working on this.}, {Account={Id=1, Name=Foo Inc}, CaseNumber=100, Contact={FirstName=Foo, LastName=Bar}, Status=Closed}]";
String statusOfCaseNumber200 = body.replaceAll(".*CaseNumber=200\\b.*?\\bStatus=([^,}]*).*", "$1");
System.out.println(statusOfCaseNumber200); // "In Progress"
PLEASE DO NOT use Genson as Hiran showed in his example. The library hasn't been updated since 2019 and has many vulnerable dependencies!
Use Jackson or Gson.
Here how you can serialize a string into a Jackson JsonNode:
ObjectMapper mapper = new ObjectMapper();
String json = ...;
JsonNode node = mapper.readTree(json);
If you want to serialize a JSON object string into a Map:
ObjectMapper mapper = new ObjectMapper();
String json = ...;
Map<String, Object> map = mapper.readValue(json, HashMap.class);
You can read more about JsonNode here and a tutorial here.
You can use JSON-Java library and your code will look like this:
JSONObject jsonObject = new JSONObject(JSON_STRING);
String status = jsonObject.getJSONArray("records")
.getJSONObject(0)
.getString("Status");
System.out.println(status);
Or in a loop
JSONArray jsonArray = new JSONObject(jsonString).getJSONArray("records");
for(int i =0; i < jsonArray.length(); i++) {
String status = jsonArray
.getJSONObject(i)
.getString("Status");
System.out.println(status);
}
So the response.getBody() is returned and when it is displayed in Postman, it looks like the pretty JSON shown above. However, when I do:
...
text.replaceAll("=", ":") would help some, but won't add quotations
marks nor would it help separate that email block.
How can I so that the responses here like ObjectMapper and JSONObject
can work?
Firstly, Jackson is the default message converter which Spring Web uses under the hood to serialize and deserialize JSON. You don't need to introduce any dependencies.
Secondly, the process serialization/deserialization is handled by the framework automatically, so that in many cases you don't need to deal with the ObjectMapper yourself.
To emphasize, I'll repeat: in most of the cases in Spring you don't need to handle raw JSON yourself. And in the body of ResponseEntiry<Object> produced by the method RestTemplate.exchange() you have a LinkedHashMap in the guise of Object, it's not a raw JSON (if you want to know why it is a LinkedHashMap, well because that's how Jackson stores information, and it's a subclass of Object like any other class in Java). And sure, when you're invoking toString() on any implementation of the Map you'll get = between a Key and a Value.
So, the problem you've mentioned in the updated question is artificial.
If you want to deal with a Map instead of an object with properly typed properties and here's how you can do that:
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<LinkedHashMap<String, Object>> response = restTemplate.exchange(
sfdcURL, HttpMethod.POST, entity, new ParameterizedTypeReference<>() {}
);
Map<String, Object> resMap = response.getBody();
List<Object> recordsList = (List<Object>) resMap.get("records");
if (recordsList.isEmpty()) { ... }
If there are redundant lines in the Values which you want to trim, then as a remedy you can introduce a custom Jackson-module declaring a Deserializer which would handle leading/trailing white-space and new lines, described in this answer. Deserialize in the module would be applied by default, other options would require creating classes representing domain objects which you for some reasons want to avoid.
As Oliver suggested JsonNode seems to be the best approach. But, if I receive the ResponseEntity<Object>, I still cannot figure out a way to convert it to readable Json (and thus convert it to JsonNode), so I am still open to responses for that part.
I was able to get it to work by changing the ResponseEntity<Object> to ResponseEntity<JsonNode> so this is what I will be submitting for now:
ResponseEntity<JsonNode> response = restTemplate.exchange(sfdcURL,
HttpMethod.POST, entity, JsonNode.class);
JsonNode records = response.getBody().get("records");
String status = null;
String statusMessage = null;
for (JsonNode rec : records) {
if(rec.get("CaseNumber").asText().equals(caseNumber)) {
status = rec.get("Status").asText();
if(rec.has("StatusMessage")) {
statusMessage = rec.get("StatusMessage").asText();
}
} else {
statusMessage = "Invalid CaseNumber";
}
}
Because the overall method returns a ResponseEntity<Object> I then converted my strings to a HashMap and returned that:
HashMap<String, String> resMap = new HashMap<String, String>();
resMap.put("Status", status);
resMap.put("StatusMessage", statusMessage);
return new ResponseEntity<>(resMap, HttpStatus.OK);
This is not a perfect solution, but it works for now. Would still be better for exception handling if I could receive a ResponseEntity<Object> and then convert it to a JsonNode though. Thanks everyone for the responses!
I have java web application (servlet) that does user authentication using SalesForce Server OAuth Authentication Flow. This OAuth Authentication provides "state" query parameter to pass any data on callback. I have a bunch of parameters that I want to pass through this "state" query param. What is the best way to do it? In java in particularly?
Or in other words, what is the best way to pass an array or map as a single http query parameter?
You can put all in json or xml format or any other format and then encode in base64 as a one large string. Take care that params can impose some hard limit on some browser/web server.
So, I have done it this way. Thank you guys! Here are some code snippets to illustrate how it works for me:
// forming state query parameter
Map<String, String> stateMap = new HashMap<String, String>();
stateMap.put("1", "111");
stateMap.put("2", "222");
stateMap.put("3", "333");
JSONObject jsonObject = new JSONObject(stateMap);
String stateJSON = jsonObject.toString();
System.out.println("stateJSON: " + stateJSON);
String stateQueryParam = Base64.encodeBase64String(stateJSON.getBytes());
System.out.println("stateQueryParam: " + stateQueryParam);
// getting map from state query param
ObjectMapper objectMapper = new ObjectMapper();
stateMap = objectMapper.readValue(Base64.decodeBase64(stateQueryParam.getBytes()), LinkedHashMap.class);
System.out.println("stateMap: " + stateMap);
Here is output:
stateJSON: {"1":"111","2":"222","3":"333"}
stateQueryParam: eyIxIjoiMTExIiwiMiI6IjIyMiIsIjMiOiIzMzMifQ==
stateMap: {1=111, 2=222, 3=333}
I tried to send POST request with some parameters. For this I form MultivaluedMap
if I make this adding to MultivaluedMap
String ban = subscriber.getBan();
String username = user.getUsername();
postData.add("agent", username);
postData.add("datasource", "online");
postData.add("accountId", ban);
String json = RESTUtil.doPost(url, postData);
All work fine
but if I make this
postData.add("agent", user.getUsername());
postData.add("datasource", "online");
postData.add("accountId", subscriber.getBan());
String json = RESTUtil.doPost(url, postData);
I have error:
com.sun.jersey.api.client.ClientHandlerException: java.lang.ClassCastException: java.lang.String cannot be cast to java.util.List
It is my post method
public static String doPost(String url, MultivaluedMap formData) {
try {
Client client = Client.create();
WebResource wr = client.resource(url);
client.setConnectTimeout(CONNECTION_TIMEOUT);
client.setReadTimeout(READ_TIMEOUT);
ClientResponse response2 = wr
.accept("application/json;")
.type("application/x-www-form-urlencoded; charset=UTF-8")
.post(ClientResponse.class, formData);
if (response2.getStatus() != 200) {
throw new RuntimeException("Failed : HTTP error code : " + response2.getStatus());
}
return response2.getEntity(String.class);
} catch (Exception e) {
LOG.log(Level.WARNING, "callRestUrl:", e);
JsonObject jo = new JsonObject();
jo.addProperty("resultCode", "EXCEPTION");
jo.addProperty("details", e.getMessage());
return GSON.toJson(jo);
}
}
And in second case I get error after .post(ClientResponse.class, formData);
I do not understand what is wrong. subscriber.getBan() and user.getUsername() return String like ban and username, but if I use the getter, a have error.
And part 2. I found this article this article
but I do not understand when to use add or put and their difference?
Can you explicit how you create your instance of MultivaluedMap? How are you using it?
MultivaluedMap is a couple of key (single value) and value (list of objects). See the declaration:
public interface MultivaluedMap<K,V> extends Map<K,List<V>>
I suppose both of your snippets are used sequentially in the same piece of code. I the first case, you initialise the value for the key 'ban' (that's mean: the value is a list of one element), in the second case, you add a value to the list to the same key 'ban'. It happens exactly the same for the key 'username'.
I your first case, Java automatically catch the list (of one value) to a string, after the second add, this cannot be the case.
To verify it, you can simply change the order (do first your second case, then the first one). You should get the same error, after the second.
To resolve your case, consider using the method putSingle instead of add if you want to "update/replace" the value, or re-initiate your instance of formData (formData = new ...) before using it another time.
HttpGet getRequest=new HttpGet("/rest/auth/1/session/");
getRequest.setHeaders(headers);
httpResponse = httpclient.execute(target,getRequest);
entity = httpResponse.getEntity();
System.out.println(EntityUtils.toString(entity));
Output as follows in json format
----------------------------------------
{"session":{"name":"JSESSIONID","value":"5F736EF0A08ACFD7020E482B89910589"},"loginInfo":{"loginCount":50,"previousLoginTime":"2014-11-29T14:54:10.424+0530"}}
----------------------------------------
What I want to know is how to you can manipulate this data using Java without writing it to a file?
I want to print name, value in my code
Jackson library is preferred but any would do.
thanks in advance
You may use this JSON library to parse your json string into JSONObject and read value from that object as show below :
JSONObject json = new JSONObject(EntityUtils.toString(entity));
JSONObject sessionObj = json.getJSONObject("session");
System.out.println(sessionObj.getString("name"));
You need to read upto that object from where you want to read value. Here you want the value of name parameter which is inside that session object, so you first get the value of session as JSONObject using getJSONObject(KeyString) and read name value from that object using function getString(KeyString) as show above.
May this will help you.
Here's two ways to do it without a library.
NEW (better) Answer:
findInLine might work even better. (scannerName.findInLine(pattern);)
Maybe something like:
s.findInLine("{"session":{"name":"(\\w+)","value":"(\\w+)"},"loginInfo":{"loginCount":(\\d+),"previousLoginTime":"(\\w+)"}}");
w matches word characters (letters, digits, and underscore), d matches digits, and the + makes it match more than once (so it doesnt stop after just one character).
Read about patterns here https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html
OLD Answer:
I'm pretty sure you could use a scanner with a custom delimiter here.
Scanner s = new Scanner(input).useDelimiter("\"");
Should return something like:
{
session
:{
name
:
JSESSIONID
,
value
:
5F736EF0A08ACFD7020E482B89910589
And so on. Then just sort through that list/use a smarter delimiter/remove the unnecessary bits.
Getting rid of every other item is a pretty decent start.
https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html has info on this.
I higly recomend http-request built on apache http api.
private static final HttpRequest<Map<String, Map<String, String>>> HTTP_REQUEST = HttpRequestBuilder.createGet(yourUri, new TypeReference<Map<String, Map<String, String>>>{})
.addDefaultHeaders(headers)
.build();
public void send(){
ResponseHandler<Map<String, Map<String, String>>> responseHandler = HTTP_REQUEST.execute();
Map<String, Map<String, String>> data = responseHandler.get();
}
If you want use jackson you can:
entity = httpResponse.getEntity();
ObjectMapper mapper = new ObjectMapper();
Map<String, Map<String, String>> data = mapper.readValue(entity.getContent(), new TypeReference<Map<String, Map<String, String>>>{});
I'm sending a http post request from javascript, with some json data.
Javascript
var data = {text : "I neeed to store this string in database"}
var xhr= new XMLHttpRequest();
xhr.open("POST","http://localhost:9000/postJson" , true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
xhr.send(data);
xhr.setRequestHeader("Connection", "close");
//Also, I've tried a jquery POST
//$.post('postJson', {'data=' : JSON.stringify(data)});
//But this doesn't make a request at all. What am I messing up here?
Route
POST /postJson controllers.Application.postJson()
Controller
public static Result postJson(){
//What should I write here to get the data
//I've tried the below but values is showing null
RequestBody rb=request().body();
final Map<String,String[]> values=rb.asFormUrlEncoded();
}
What is the way to parse the POST request body?
Much thanks!
Retreive the request body directly as JSON... no need to complicate your life.
public static Result postJson() {
JsonNode rb = request().body().asJson();
//manipulate the result
String textForDBInsertion = rb.get("text").asText(); //retreives the value for the text key as String
Logger.debug("text for insertion: " + textForDBInsertion
+ "JSON from request: " + rb);
return ok(rb);
}
Also, I recommend you use the AdvancedRestClient Chrome plugin for testing. This way you can eliminate from the equation client-side code errors.
Cheers!