Currently, I am using rest template to get data from external api in getter method. While printing in console log, valid json format is coming. But, through postman output, invalid json output is coming (with \"). Pls suggest.
public class Product {
#Id
public Integer id;
private String name;
public Product() {
}
public Product(Integer id, String name) {
this.id = id;
this.name = name;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
final String uri = "http://example.com/";
RestTemplate restTemplate = new RestTemplate();
String result = restTemplate.getForObject(uri + this.getId(), String.class);
System.out.println(result);
return result;
}
public void setName(String name) {
this.name = name;
}
}
//console.log (example)
{"product":{"rating_and_review_reviews":{"hasErrors":false,"offset":0,
"totalResults":0,"locale":"en_US","limit":10,"duration":1,"result":
[]},"question_answer_statistics"
// POSTMAN - HTTP GET (coming with \)
{
"id": 1,
"name": "{\"product\":{\"rating\":{\"hasErrors\":false,\"offset\":0,
\"totalResults\":0,\"locale\":\"en_US\",\"limit\":10,
\"duration\":1,\"result\":[]}
Related
#Component
public class JsonData {
#JsonProperty("id")
private Integer id;
#JsonProperty("createdAt")
private Date cratedAt;
#JsonProperty("name")
private String name;
#JsonProperty("email")
private String email;
#JsonProperty("imageUrl")
private String url;
public JsonData() {
}
public JsonData(Integer id, Date cratedAt, String name, String email, String url) {
this.id = id;
this.cratedAt = cratedAt;
this.name = name;
this.email = email;
this.url = url;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Date getCratedAt() {
return cratedAt;
}
public void setCratedAt(Date cratedAt) {
this.cratedAt = cratedAt;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
}
Controller
#RestController
public class JsonDataController {
#RequestMapping(value = "/template/products")
public void getAllData() {
RestTemplate template = new RestTemplate();
String url = "https://5ef99e4bbc5f8f0016c66d42.mockapi.io/testing/data";
ResponseEntity < JsonData[] > response = template.exchange(url, JsonData[].class);
for (JsonData jsonData: response.getBody()) {
System.out.println(jsonData.getName());
System.out.println(jsonData.getEmail());
}
}
}
I am trying to print json data that is array using rest template but I am getting error in this line "ResponseEntity < JsonData[] > response = template.exchange(url, JsonData[].class);" my error is "cannot resolve method" Can anyone tell me correct way of doing this .I am new to spring I do not have proper understanding it would be helpful if some one can give their suggeestion in this code
RestTemplate does not have any method with signature exchange(String, Class<T>).
That is why you are getting "cannot resolve method" error for template.exchange(url, JsonData[].class);.
Here is an example of correct usage of one of the methods from RestTemplate.exchange API:
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<JsonData[]> response = restTemplate.exchange(url, HttpMethod.GET, null, JsonData[].class);
RestTemplate also has another method - getForEntity that makes a GET call with the given URL and expected return type. (without need for passing null for not required fields)
RestTemplate template = new RestTemplate();
String url = "https://5ef99e4bbc5f8f0016c66d42.mockapi.io/testing/data";
ResponseEntity <JsonData[]> response = template.getForEntity(url, JsonData[].class);
I am trying to create a service which fetch image of a student along with other text details of student stored in database and display it on an html page. I tried but some hash value is being returned.
My Model Class
#Entity
#Table(name = "details")
public class Student {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
#Column(name = "name")
private String name;
#Column(name = "pic" , length = 2000)
private byte[] pic;
public Student(long id, String name, byte[] pic) {
super();
this.id = id;
this.name = name;
this.pic = pic;
}
public Student() {
super();
// TODO Auto-generated constructor stub
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public byte[] getPic() {
return pic;
}
public void setPic(byte[] pic) {
this.pic = pic;
}
#Override
public String toString() {
return "Student [id=" + id + ", name=" + name + "];
}
}
Without Using a rest contoller will it be achieved like this?
My Controller
#Controller
public class ImgShowController {
#Autowired
EntityRepository entityRepository;
#RequestMapping("/list")
public String getAllStudents(Model model) {
List<Imge> list = (List<Imge>) entityRepository.findAll();
model.addAttribute("students", list);
return "liststudents";
}
#RequestMapping(path= {"/particularlist","/particularlist/{id}"})
public String getImage(#PathVariable("id") Long id, Model model) {
final Optional<Student> imget = entityRepository.findById(id);
Imge imge = new Imge(imget.get().getId(), imget.get().getName(), decompressBytes(imget.get().getPic()));
model.addAttribute("particularStudent", imge);
return "particularstudent";
}
}
Decompress Byte function
public static byte[] decompressBytes(byte[] data) {
Inflater inflater = new Inflater();
inflater.setInput(data);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream(data.length);
byte[] buffer = new byte[1024];
try {
while (!inflater.finished()) {
int count = inflater.inflate(buffer);
outputStream.write(buffer, 0, count);
}
outputStream.close();
} catch (IOException ioe) {
} catch (DataFormatException e) {
}
return outputStream.toByteArray();
}
First of all, I would suggest mentioning that you store binary object (LOB) in pic column in your entity class:
#Lob
#Column(name = "pic" , length = 2000)
private byte[] pic;
And then, it seems that Thymeleaf does not allow you to inject image directly into model, so you have 2 ways to accomplish this:
1.Adding another controller to serve you images
#GetMapping("/students/{id}/image")
public void studentImage(#PathVariable String id, HttpServletResponse response) throws IOException {
var student = entityRepository.findById(id);
var imageDecompressed = decompressBytes(student.get().getPic());
response.setContentType("image/jpeg");
InputStream is = new ByteArrayInputStream(imageDecompressed);
IOUtils(is, response.getOutputStream());
}
and then referring to it from model like this:
<img th:src="#{'students/' + #{studentId} + '/image'}">
2.Using base64
You need to encode image as base64 string:
var base64EncodedImage = Base64.getEncoder().encodeToString(imageData);
and then setting into model like this:
<img th:src="#{'data:image/jpeg;base64,'+${base64EncodedImage}}"/>
I would suggest using the first way because otherwise you would depend on image size and overall payload would be 30% larger (base64), so by using the first way you let user's browser decide how and when to load particular image
I'm trying to build a Spring WebFlux project and realize the follow business logic:
1 - Call an external REST Api using WebClient and parse the Json results using the Models below. It is working OK
2 - To show the Mono results Mono<DeviceList> devices, I'm using the ResponseApi class and returning it, but it is NOT working
I'm getting the follow error:
Response status 406 with reason "Could not find acceptable representation"
Thanks
# Json Result
{
"data": [
{
"id": "5bc3c0efe833d93f401bafa8",
"name": "XXXXX",
"group": "5b8fd1fa0499f54cfa7febb8",
"description": "Geolocalizacao gps",
"payloadType": "None",
"contract": "5bc08be5e833d93f40e1f936",
"keepAlive": 0
}
]
}
# Controller
public class DeviceController{
...
...
#RequestMapping(value = V1 + BASE_URL + "/devices/types", method = GET, produces = APPLICATION_JSON)
public Mono<ServerResponse> getDeviceTypes(){
Mono<DeviceList> devices = deviceService.findDeviceTypes();
ResponseApi r = new ResponseApi();
r.setMessage("Test");
r.setCode("200");
r.setStatus(200);
r.setData(devices);
return ok().body(Mono.just(r), ResponseApi.class);
}
}
# Repository
public Mono<DeviceList> findDeviceTypes() {
return webClient.get()
.uri(DEVICE_TYPES_URL)
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.bodyToMono(DeviceList.class);
}
# Model
public class DeviceList{
#JsonProperty("data")
private List<Device> data;
public List<Device> getData() {
return data;
}
public void setData(List<Device> data) {
this.data = data;
}
}
public class Device{
#JsonProperty("id")
private String id;
#JsonProperty("name")
private String name;
#JsonProperty("group")
private String group;
#JsonProperty("description")
private String description;
#JsonProperty("keepAlive")
private Integer keepAlive;
#JsonProperty("payloadType")
private String payloadType;
#JsonProperty("contract")
private String contract;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGroup() {
return group;
}
public void setGroup(String group) {
this.group = group;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public Integer getKeepAlive() {
return keepAlive;
}
public void setKeepAlive(Integer keepAlive) {
this.keepAlive = keepAlive;
}
public String getPayloadType() {
return payloadType;
}
public void setPayloadType(String payloadType) {
this.payloadType = payloadType;
}
public String getContract() {
return contract;
}
public void setContract(String contract) {
this.contract = contract;
}
}
#JsonRootName("data")
public class ResponseApi{
#JsonProperty("status")
private Integer status;
#JsonProperty("code")
private String code;
#JsonProperty("message")
private String message;
#JsonProperty("data")
private Object data;
public Integer getStatus() {
return status;
}
public void setStatus(Integer status) {
this.status = status;
}
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public Object getData() {
return data;
}
public void setData(Object data) {
this.data = data;
}
}
You can get devices, then in non blocking way, map them to the ResponseApi like that:
#RequestMapping(value = V1 + BASE_URL + "/devices/types", method = GET, produces = APPLICATION_JSON)
public Mono<ServerResponse> getDeviceTypes(){
return deviceService.findDeviceTypes()
.flatMap(devices -> {
ResponseApi r = new ResponseApi();
r.setMessage("Test");
r.setCode("200");
r.setStatus(200);
r.setData(devices);
return ok().body(Mono.just(r), ResponseApi.class);
});
}
I know the meaning of the error but can't debug it.
My Bean class is :
public class User {
private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
My Controller is:
#RequestMapping(value = "/user/create", method = RequestMethod.POST)
public ResponseEntity<Void> createUser(#RequestBody User user, UriComponentsBuilder ucBuilder) {
System.out.println("Creating User " + user.getName());
HttpHeaders headers = new HttpHeaders();
headers.setLocation(ucBuilder.path("/user/{id}").buildAndExpand(user.getName()).toUri());
return new ResponseEntity<Void>(headers, HttpStatus.CREATED);
}
As in spring-data-dynamoDB demo, I have created my application with hash and range keys, but am unable to post any data into my Table using POST because the following exception,
{cause: {cause: {cause: null,message: null}, message: "N/A (through reference chain: pkg.Test["id"])"}, message: "Could not read JSON: N/A (through reference chain: pkg.Test["id"]); nested exception is com.fasterxml.jackson.databind.JsonMappingException: N/A (through reference chain: pkg["id"])"
}
My Domain Class,
#DynamoDBTable(tableName = "test")
public class Test implements Serializable{
private static final long serialVersionUID = 1L;
#Id private TestId testId;
private String description;
private String testing;
#DynamoDBHashKey(attributeName="id")
public String getId() {
return testId != null ? testId.getId() : null;
}
public void setId(String id) {
if(testId == null){
testId = new TestId();
}
this.setId(id);
}
#DynamoDBRangeKey(attributeName="name")
public String getName() {
return testId != null ? testId.getName() : null;
}
public void setName(String name) {
if(testId == null){
testId = new TestId();
}
this.setName(name);
}
#DynamoDBAttribute(attributeName="description")
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
#DynamoDBAttribute(attributeName="testing")
public String getTesting() {
return testing;
}
public void setTesting(String testing) {
this.testing = testing;
}
public TestId getTestId() {
return testId;
}
public void setTestId(TestId testId) {
this.testId = testId;
}
}
and my TestId Class,
public class TestId implements Serializable{
private String id;
private String name;
#DynamoDBHashKey
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
#DynamoDBRangeKey
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
I think I have created Domain class correctly but What is the correct procedure to Post data into it. I have tried,
URL:
http://localhost:8080/tests
Request Body:
{"testId": {"id": "test", "name": "z"}, "description": "Awesome Guy", "testing": "x"}
and
{"id": "test", "name": "z", "description": "Awesome Guy", "testing": "x"}
But all shows the exception as I mentioned above but I have given id attribute in requestbody correctly.
What is the correct procedure to POST the data into my table? and Is there anything problem with spring-data-rest parsing? as mentioned here
The setId() method seems to be self-calling. You may want to call testId.setId() instead of this.setId().