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Retrieve value from returned JSON object in Java

I am a receiving a JSON object and I need to save the values to my DB. But I'm having an issue figuring out how to retrieve the particular values in the JSON object.
In this case, I want to retrieve the values of 'originationNumber' and 'messageBody'
The response object -
{"originationNumber":"***","destinationNumber":"***","messageKeyword":"KEYWORD_***","messageBody":"Answer ","previousPublishedMessageId":"1slamq6mdpucd8q4i7iabf1sikc629ga253tr6o0","inboundMessageId":"88bc02fc-aff3-4277-ac1d-f27b6d3b6abb"}
Method to receive message -
public String getReceivedMessages(Messaging receivedMessage) {
BasicAWSCredentials awsCredentials = new BasicAWSCredentials(awsAccessKey, awsSecretKey);
AmazonSQS sqsClient = AmazonSQSClientBuilder.standard()
.withCredentials(new AWSStaticCredentialsProvider(awsCredentials))
.withRegion(String.valueOf(awsRegion)).build();
StringBuilder sb = new StringBuilder();
String queueUrl = "https://sqs.us-east-1.amazonaws.com/1234567/GetReceivedMessages";
List<Message> messages = sqsClient.receiveMessage(new ReceiveMessageRequest(queueUrl)
.withMaxNumberOfMessages(1).withWaitTimeSeconds(20)).getMessages();
for (Message message : messages) {
sb.append(message.getBody());
sqsClient.deleteMessage(queueUrl, message.getReceiptHandle());
}
// Save messages to DB
String userId = connectionRequestRepository.getUserId();
Date date = new Date();
Timestamp now = new Timestamp(date.getTime());
receivedMessage.setUserId(userId);
receivedMessage.setOriginationNumber("");
receivedMessage.setDestinationNumber("***");
receivedMessage.setMessageBody("");
receivedMessage.setMessageType("RECEIVED");
receivedMessage.setCreatedAt(now);
messagingRepository.save(receivedMessage);
System.out.println(sb); <--- Prints response object to console
return sb.toString();
}

You can use jackson library for that.
Solution 1: You can use ObjectMapper as below:
Message Class to map JSON to Java Object:
public class Message {
private String originationNumber;
private String messageBody;
// public getter and setters methods
}
Create Object From JSON String:
Message message = null;
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
try {
message = objectMapper.readValue(payload, Message.class);
} catch (JsonProcessingException e) {
// Log Or do some action as per need
}
Here message will have those values. DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES is used here to skip exception as there are other fields also in JSON and not present in Java Class (as we don't need them).
Solution 2: Alternatively you can use JsonNode from same Jackson library and read nodes one by one as below:
ObjectMapper mapper = new ObjectMapper();
JsonNode actualObj = mapper.readTree("{\"originationNumber\":\"***\",\"destinationNumber\":\"***\",\"messageKeyword\":\"KEYWORD_***\",\"messageBody\":\"Answer \",\"previousPublishedMessageId\":\"1slamq6mdpucd8q4i7iabf1sikc629ga253tr6o0\",\"inboundMessageId\":\"88bc02fc-aff3-4277-ac1d-f27b6d3b6abb\"}");
String originationNumber = actualObj.get("originationNumber");
String messageBody = actualObj.get("messageBody");
In this approach you won't need to create Message class.

You can convert the json string into a json object
https://www.javatpoint.com/how-to-convert-string-to-json-object-in-java
String string = "{\"originationNumber\":\"***\",\"destinationNumber\":\"***\",\"messageKeyword\":\"KEYWORD_***\",\"messageBody\":\"Answer \",\"previousPublishedMessageId\":\"1slamq6mdpucd8q4i7iabf1sikc629ga253tr6o0\",\"inboundMessageId\":\"88bc02fc-aff3-4277-ac1d-f27b6d3b6abb\"}";
JSONObject json = new JSONObject(string);
System.out.println(json.toString());
String destinationNumber = json.getString("destinationNumber");
System.out.println(destinationNumber);

where ur json like
{"originationNumber":"***",
"destinationNumber":"***",
"messageKeyword":"KEYWORD_***",
"messageBody":"Answer","previousPublishedMessageId":"1slamq6mdpucd8q4i7iabf1sikc629ga253tr6o0",
"inboundMessageId":"88bc02fc-aff3-4277-ac1d-f27b6d3b6abb"
}
it like
"key":Value
i think ur code will be like
receivedMessage.setUserId(userId);
receivedMessage.setOriginationNumber("originationNumber");
receivedMessage.setDestinationNumber("destinationNumber");
receivedMessage.setMessageBody("messageBody");
receivedMessage.setMessageType("RECEIVED");
receivedMessage.setCreatedAt(now);
messagingRepository.save(receivedMessage);

JSON Response Has Escaped Quotations Using Jackson and JAX-RS Exception Mapper

I have a simple requirement where, if application encounters an exception, my JAX-RS Rest endpoint should return a custom JSON response with 500 HTTP header status.
Data needed to construct the response comes from an object with several properties (see below). The problem is, I am only interested in one or two values from each property (out of several dozens). And I cannot modify any of these models/classes (some have a Jackson annotation for JSON processing, e.g. null properties should be discarded during serialization).
public class MainObject {
private FirstProperty firstProperty;
private SecondProperty secondProperty;
private ThirdProperty thirdProperty;
// other codes
public String toString() {
ObjectMapper mapper = new ObjectMapper();
try { return mapper.writeValueAsString(this); }
catch (Exception e) { return null; }
}
}
public class FirstProperty {
private boolean bol = true;
private double dob = 5.0;
private List<String> subProperty;
// other properties
public String toString() {
ObjectMapper mapper = new ObjectMapper();
try { return mapper.writeValueAsString(this); }
catch (Exception e) { return null; }
}
}
#JsonSerialize(include=JsonSerialize.Inclusion.NON_NULL)
public class SecondProperty {
private String str;
private List<String> subProperty;
// other properties
public String toString() {
ObjectMapper mapper = new ObjectMapper();
try { return mapper.writeValueAsString(this); }
catch (Exception e) { return null; }
}
}
#JsonSerialize(include=JsonSerialize.Inclusion.NON_NULL)
public class ThirdProperty {
private int intProp = true;
private List<String> subProperty;
// other properties
public String toString() {
ObjectMapper mapper = new ObjectMapper();
try { return mapper.writeValueAsString(this); }
catch (Exception e) { return null; }
}
}
The expected JSON that I should be seeing coming back is on the client side (say, a browser -- testing in Edge):
{
"firstProperty" : { "subProperty" : [ "val1" ] },
"secondProperty" : { "str" : "val2", "subproperty" : [ "val3", "val6" ] },
"thirdProperty" : { "subProperty" : [ "val4" ] }
}
Instead, all my field names and their values have their quotations escaped, and extra double quotes around the entire value, e.g.:
{
"firstProperty" : "{ \"subProperty\" : [ \"val1\" ] }",
"secondProperty" : "{ \"str\" : \"val2\", \"subproperty\" : [ \"val3\", \"val6\" ] }",
"thirdProperty" : "{ \"subProperty\" : [ \"val4\" ] }"
}
Please note the extra " before and after the curly brackets. My environment is:
Java 1.8.45
FasterXML Jackson 2.9.8
Spring Boot 2.0.1
RestEasy (JBoss) JAX-RS
JBoss 6.4
I eliminated the majority of "noise" in the code to see at what point this happens. This is the controller:
#Path("/")
public class MainController {
#GET
#Produces(MediaType.APPLICATION_JSON)
#Path("/rest/path")
public MainObject getMainObject throws MyCustomException {
// A service call that throws MyCustomException
}
}
And JAX-RS ExceptionMapper where I send the response back:
#Provider
public class MyCustomExceptionMapper extends ExceptionMapper<MyCustomException> {
#Override
public Response toResponse(MyCustomException ex) {
HashMap<String, Object> responseBody = new HashMap<>();
String strEx = ex.getStrEx(); // Comes from SecondProperty.str stored in MyCustomException, not that it matters
// Instantiate an empty object that contains
MainObject obj = new MainObject();
obj.getFirstProperty().setSubProperty(ex.getStrs());
obj.getSecondProperty().setStr(strEx);
obj.getSecondProperty().setSubProperty(ex.getStrs());
obj.getThirdProperty().setSubProperty(ex.getStrs());
responseBody.put("firstProperty", serializeFirstProperty(obj.getFirstProperty()));
responseBody.put("secondProperty", serializeSecondProperty(obj.getSecondProperty()));
responseBody.put("thirdProperty", serializeThirdProperty(obj.getThirdProperty()));
Response response = Response.status(/* 500 status */).entity(responseBody).build();
return response;
}
}
Since I only need to send back a very small subset of overall properties from each of my types, I created a custom StdSerializer that would only populate a needed property. For brevity, I only do serializeFirstProperty() but they are all more or less identical:
private StdSerializer<FirstProperty> getFPSerializer(FirstProperty firstProperty) {
return new StdSerializer<FirstProperty>(FirstProperty.class) {
#Override
public void serialize(FirstProperty value, JsonGenerator gen, SerializerProvider provider) throws IOException {
gen.writeStartObject();
if (/* there are items in FirstProperty.subProperty */) {
gen.writeArrayFieldStart("subProperty");
for (String str : value.getSubProperty()) {
gen.writeString(str);
}
gen.writeEndArray();
}
gen.writeEndObject();
}
}
private <T> ObjectMapper getCustomOM(StdSerializer<?> serializer) {
ObjectMapper mapper = new ObjectMapper();
SimpleModule sm = new SimpleModule();
sm.addSerializer(serializer);
mapper.registerModule(module);
return mapper;
}
Then use these helper methods like:
private String serializeFirstProperty(FirstProperty firstProperty) {
ObjectMapper mapper = getCustomOM(getFPSerializer(firstProperty));
String ser = null;
try { ser = mapper.writeValueAsString(firstProperty); }
catch (JsonProcessingException e) { return null; }
return ser;
}
I have tried countless of configurations with ObjectMapper, e.g. disable(JsonParser.Feature.ALLOW_BACKLASH_ESCAPING_ANY_CHARACTER) (couldn't find any relevant flag for JsonGenerator which I really want to disable in a similar fashion).
Or explicitly returning Object from serializeFirstProperty(), or replacing all the \" with " in serializeFirstProperty() when ser is returned.
Or set custom StdSerializer's JsonGenerator.setCharacterEscapes(new CharacterEscapes() { //... } or play around with JAX-RS Response at no avail. I always seem to get a "string" value with quotations, e.g.:
"firstProperty" : "{ \"subProperty\" : [ \"val1\" ] }"
If I simply just do
responseBody.put("firstProperty", mapper.writeValueAsString(obj.getFirstProperty()));
somehow this produces the right JSON output, however, it includes a lot of unnecessary properties which I don't want in this exception handling case.
Funny thing is, when I peer into response (or responseBody map), everything looks right (I don't see values having double quotations).
Please also note that not only I can't modify the models, but some of their properties are instantiated during creation with default values, so not-null inclusion doesn't work, and they will appear in the final JSON if I don't use a custom serialization.
Does anyone know what's causing this escaped and extra quotations?

I think I misunderstood the question in the first attempt of answering it.
The problem is that you serialize a property as string (using mapper.writeValueAsString(this) and then add it to the responseBody which you think of being string to json object map but it is a string to Java object map. In your case at runtime it is a string mapping to another string (the serialized json object is represented as Java string) and a Java string is a Java object as well.
What you want to do instead is to construct a Java object responseBody instead of a map. It should act as a DTO having all the specific properties etc and then serializing it in in one action using the mapper. Because if you first serialize a property to a json string than it it is just a string from the Java point of view and the mapper has no chance to interpret it as a json object.

Spring Boot 2 WebClient response convert JSON to HashMap

I would like to get a response from WebClient and convert it to just a Map without creating any Class for the response. Is it possible? So I would like something like this below. The code below is not a valid code, it is just an idea of what I want.
public Map<String, String> someFunction() {
return webClient.post()
.uri("/some/path")
.retrieve()
.bodyToFlux(HashMap.class)
.block();

If you're interested in saving a LOC, you may want to look at a core Spring Framework class: ParameterizedTypeReference<T>, found here.
public Map<String, String> someFunction() {
return webClient.post()
.uri("/some/path")
.retrieve()
.bodyToFlux(new ParameterizedTypeReference<Map<String,String>>(){})
.block();
}
Cheers.

I would first try getting the response object into a String and also make sure I am accepting JSON type in return. Once I get the respone into a String, you can try using fasterxml's jackson databind library which can convert a JSON string into Hashmap.
For example
ObjectMapper mapper = new ObjectMapper();
String json = "{\"name\":\"abc\", \"age\":25}";
Map<String, Object> map = new HashMap<String, Object>();
// convert JSON string to Map
map = mapper.readValue(json, new TypeReference<Map<String, String>>(){});
System.out.println(map);
Here is the databind library and core library java docs link
jackson-databind
jackson-core

I solved it like this:
public Map<String, String> someFunction() {
return webClient.post()
.uri("/some/path")
.retrieve()
.bodyToFlux(TypedMap.class)
.block();
}
private static class TypedMap extends HashMap<String, String>{}

JSON file printed with bars separating fields

I need to send a minified JSON to a rest service, it seemed all right, however, when printing my JSON into a file several "/" slashes appear separating the fields from the file, as I am new to this type of implementation I was confused ...
Basically, I add objects to a list and at the end, I convert the generic list to Json, this is my method that converts the List object to JSON
public String convertListToJson(List obj) throws IOException {
String jsonInString = null;
ObjectMapper mapper = new ObjectMapper();
mapper.setDefaultPropertyInclusion(JsonInclude.Include.ALWAYS);
mapper.configure(SerializationFeature.USE_EQUALITY_FOR_OBJECT_ID, true);
jsonInString = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj);
JsonNode jsonNode = mapper.readValue(jsonInString, JsonNode.class);
String json = jsonNode.toString();
return json;
}
String payload = convertListToJson(object);
System.out.println(payload);
This is the result of printing on the console
[{"id":12,"nomePeriodo":"2012","inicio":"2012-01-01T02:00:00Z","fim":"2012-12-31T02:00:00Z"},{"id":13,"nomePeriodo":"2013","inicio":"2013-01-01T02:00:00Z","fim":"2013-12-31T02:00:00Z"},{"id":14,"nomePeriodo":"2014","inicio":"2014-01-01T02:00:00Z","fim":"2014-12-31T02:00:00Z"},{"id":15,"nomePeriodo":"2015","inicio":"2015-01-01T02:00:00Z","fim":"2015-12-31T02:00:00Z"},{"id":16,"nomePeriodo":"2016","inicio":"2016-01-01T02:00:00Z","fim":"2016-12-31T02:00:00Z"},{"id":17,"nomePeriodo":"2017","inicio":"2017-01-01T02:00:00Z","fim":"2017-12-31T02:00:00Z"},{"id":18,"nomePeriodo":"2018","inicio":"2018-01-01T02:00:00Z","fim":"2018-12-31T02:00:00Z"}]
This is the method I use for printing to file
printJson(payload);
private void printJson(String payload) {
ObjectMapper mapper = new ObjectMapper();
try {
mapper.writeValue(new File("c:\\server\\JSON.json"), payload);
} catch (IOException e) {
e.printStackTrace();
}
}
When I print to a file this is the result:
"[{\"id\":12,\"nomePeriodo\":\"2012\",\"inicio\":\"2012-01-01T02:00:00Z\",\"fim\":\"2012-12-31T02:00:00Z\"},{\"id\":13,\"nomePeriodo\":\"2013\",\"inicio\":\"2013-01-01T02:00:00Z\",\"fim\":\"2013-12-31T02:00:00Z\"},{\"id\":14,\"nomePeriodo\":\"2014\",\"inicio\":\"2014-01-01T02:00:00Z\",\"fim\":\"2014-12-31T02:00:00Z\"},{\"id\":15,\"nomePeriodo\":\"2015\",\"inicio\":\"2015-01-01T02:00:00Z\",\"fim\":\"2015-12-31T02:00:00Z\"},{\"id\":16,\"nomePeriodo\":\"2016\",\"inicio\":\"2016-01-01T02:00:00Z\",\"fim\":\"2016-12-31T02:00:00Z\"},{\"id\":17,\"nomePeriodo\":\"2017\",\"inicio\":\"2017-01-01T02:00:00Z\",\"fim\":\"2017-12-31T02:00:00Z\"},{\"id\":18,\"nomePeriodo\":\"2018\",\"inicio\":\"2018-01-01T02:00:00Z\",\"fim\":\"2018-12-31T02:00:00Z\"}]"
So you have these \ bars separating the items in json...
Am I doing something wrong or is this common?
If possible I would like to remove them from my archive

JsonParseException: Unexpected character ('i' (code 105)): was expecting double-quote

I am trying to integrate Spring Cloud streams and publishing a custom Java Object across services with RabbitMQ as broker. The object I am publishing looks like:
public class AppMessageEnvelope implements Serializable {
...
private Object messageBody;
private Date sentAt = new Date();
...
// setters and getters
}
This is just a wrapper object and the original object is put in messageBody. The object I am putting in messageBody looks like:
public class Job {
...
private String message;
private Map<MyEnum, String> myMap;
...
}
Note that both AppMessageEnvelope and Job are in a different model project which is imported as a Maven dependency in the publisher and subscriber Spring Boot projects, so models are exactly the same.
In producer, I publish the object as:
#EnableBinding(Source.class)
public class JobDistributor {
private final Source jobQueue;
#Autowired
public JobDistributor(Source jobQueue) {
this.jobQueue = jobQueue;
}
public AppMessageEnvelope publishJob(AppMessageEnvelope message) {
LOG.info("Sending message: {}.", message);
jobQueue.output().send(MessageBuilder.withPayload(message).build());
return message;
}
}
In consumer, I get the message as:
#Component
#EnableBinding(Sink.class)
public class JobConsumer {
private final JobManager jobManager;
private final ObjectMapper objectMapper;
#Autowired
public JobConsumer(
JobManager jobManager, ObjectMapper objectMapper) {
this.jobManager = jobManager;
this.objectMapper = objectMapper;
}
#StreamListener(target = Sink.INPUT)
public void processData(AppMessageEnvelope messageEnvelope) {
LOG.info("Envelope received: {}.", messageEnvelope);
try {
TypeReference<Job> mapType = new TypeReference<Job>() {};
Job job = objectMapper.readValue(messageEnvelope.getMessageBody().toString(), mapType);
jobManager.processRequest(job);
} catch (Exception ex) {
LOG.error("Couldn't convert to correct object for processing: {}.", ex);
}
}
}
I try to use TypeReference to convert the internal object into a correct object but I get an error as:
JobConsumer - Couldn't convert to correct object for processing: {}.
com.fasterxml.jackson.core.JsonParseException: Unexpected character ('i' (code 105)): was expecting double-quote to start field name
at [Source: (StringReader); line: 1, column: 3]
Before the message is converted, I log it:
JobConsumer - Envelope received: AppMessageEnvelope{..., messageBody={id=5bf3a7302dbe9c7cf9927c60, jobId=8c0bfcb0b21248e694b5cd52337a1f9e, submittedAt=2018-11-20T06:18:24+0000, lastUpdatedOn=null, message=null, ..., fileContentMap={FILE_BYTES=JVBERi0xLjUKJb/3ov}}, sentAt=Tue Nov 20 11:48:24 IST 2018}
I tried configuring ObjectMapper as:
#Autowired
private ObjectMapper objectMapper() {
JsonFactory factory = new JsonFactory();
factory.enable(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES);
return new ObjectMapper(factory);
}
I tried enabling unquoting fields with this too:
objectMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
I tried solutions provided by this blog and some similar SO problem but nothing solved. What am I missing?

Use below json conversion to convert JSON to Model / Entity
ObjectMapper objectMapper = new ObjectMapper();
Job job = objectMapper.convertValue(messageEnvelope.getMessageBody().toString(), Job.class);

This may be funny error please copy your json and past into online json formatter.
if the validation wrong please rewrite the json manually or encode it.
Error cause: character encoding issue at time of copy from various sources

Here the problem:
Job job = objectMapper.readValue(messageEnvelope.getMessageBody().toString(), mapType);
Just like this:
Job job = objectMapper.readValue(objectMapper.writeValueAsString(messageEnvelope.getMessageBody()), mapType);