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Put method using a mapped class (use setters for specified parameter) - Spring boot API

I'm trying to make a PUT request for an object using only one function for all parameters. Let's say I have this object structure (JSON):
{
"id": 3,
"name": "test",
"dominio": "dom",
"altas": "6",
"bajas": "2",
"default_group": [
{
"idRef": 1,
"name": "Users",
"path": "OU=es"
}
],
"office": [
{
"idRef": 1,
"title": "Intern",
"name": "CN=Office license",
"path": "OU=licenseOffice"
},
{
"idRef": 2,
"title": "Specialist",
"name": "CN=Office License F3",
"path": "OU=LicenseGroupF"
}
]
}
I managed to do this for a GET Request using a Map function with the getters of the class.
To do this, I passed the attribute name in the HTTP request using a GET Request:
Map<String, Function<Compania, Object>> mapCompania = Map.of(
"name", Compania::getName,
"dominio", Compania::getDominio,
"altas", Compania::getAltas,
"bajas", Compania::getBajas,
"default_group", Compania::getDefault_group,
"office", Compania::getOffice
);
Function<Compania, Object> retriever = mapCompania.get(fieldName);
But now, I can't find a way to implement this same thing but in order to use the setter methods. Something like:
PUT localhost/myClass/3/name --> it uses MyClass.setName(input...)
Or:
PUT localhost/myClass/3/office --> it uses MyClass.setOffice(Object office)
Could anyone help me to achieve this? Thank you very much

Assuming that Compania is as follows:
public class Compania {
private Object name;
private Object dominio;
private Object altas;
private Object bajas;
private Object default_group;
private Object office;
public Object getName() {
return name;
}
public void setName(Object name) {
this.name = name;
}
public Object getDominio() {
return dominio;
}
public void setDominio(Object dominio) {
this.dominio = dominio;
}
public Object getAltas() {
return altas;
}
public void setAltas(Object altas) {
this.altas = altas;
}
public Object getBajas() {
return bajas;
}
public void setBajas(Object bajas) {
this.bajas = bajas;
}
public Object getDefault_group() {
return default_group;
}
public void setDefault_group(Object default_group) {
this.default_group = default_group;
}
public Object getOffice() {
return office;
}
public void setOffice(Object office) {
this.office = office;
}
}
The code below should do the trick:
Map<String, BiConsumer<Compania, Object>> mapCompaniaSetters = Map.of(
"name", Compania::setName,
"dominio", Compania::setDominio,
"altas", Compania::setAltas,
"bajas", Compania::setBajas,
"default_group", Compania::setDefault_group,
"office", Compania::setOffice
);
BiConsumer<Compania, Object> setter = mapCompaniaSetters.get(fieldName);
We can test this as follows to check that it actually works:
public static void main(String[] args) {
Map<String, BiConsumer<Compania, Object>> mapCompaniaSetters = Map.of(
"name", Compania::setName,
"dominio", Compania::setDominio,
"altas", Compania::setAltas,
"bajas", Compania::setBajas,
"default_group", Compania::setDefault_group,
"office", Compania::setOffice
);
BiConsumer<Compania, Object> setter = mapCompaniaSetters.get("name");
Compania compania = new Compania();
System.out.println("Empty Compania: " + compania);
setter.accept(compania, "Test");
System.out.println("Compania with Name: " + compania);
}

How to template a json in java programming

My Use case is I have a json file but I have to share only few of them to client.
Ex: Consider the source json file as shown below.
{
"name": "XYZ",
"age": 24,
"education": {
"college": "ppppp",
"study": "b.tech",
"grade": 6.8
},
"friends": ["kkkk",
"bbbbbbbbbbb",
"jjjjjj"],
"dob":"01-08-1990"
}
For client 1 I have to share below output
{
"personalInfo": {
"name": "XYZ",
"age": 24,
"friendsNames": ["kkkk","bbbbbbbbbbb","jjjjjj"]
},
"educationalInfo": {
"college": "ppppp",
"study": "b.tech",
"grade": 6.8
}
}
For client 2 I have to share below output
{
"personalInformation": {
"nameOfEmployee": "XYZ",
"ageOfEmployee": 24
},
"educationalInformation": {
"college": "ppppp",
"study": "b.tech"
}
}
And for other clients also the use case is same, I have to skip some keys and give different names to the keys. How to dynamically do this by some kind of configuration. I used jsonPath to achieve this but removing few keys from json object is difficult. Any suggestions can be appreciated.

Use a JSON Path library, like JayWay. With that, templates to transform your exapmle would be:
Client 1
{
"personalInfo": {
"name": "$.name",
"age": "$.age",
"friendsNames": "$.friends"
},
"educationalInfo": "$.education"
}
Client 2
{
"personalInformation": {
"nameOfEmployee": "$.name",
"ageOfEmployee": "$.age"
},
"educationalInformation": {
"college": "$.education.college",
"study": "$.education.study"
}
}
What you need to implement is the template traversal. It's about 20 lines of code; or 40 if you also need to transform list elements, like:
{
"friends": [ "$.friends[?(# =~ /.{5,}/)]", {
"name": "#",
"since": "$.dob"
} ]
}
which would result into:
{
"friends": [ {
"name": "bbbbbbbbbbb",
"since": "01-08-1990"
}, {
"name": "jjjjjj",
"since": "01-08-1990"
} ]
}

You can use Jackson to serialize and deserialize json. I suggest you to create seperate classes which represents your client data.
I show you an example of how you can deserialize your data and map it to your client json.
You can generate corresponding classes for client 2 with getting some help from http://www.jsonschema2pojo.org/ for mapping json to pojo.
Here is the code :
public class Main {
public static void main(String[] args) throws ParseException, ParserConfigurationException, IOException, SAXException {
ObjectMapper mapper = new ObjectMapper();
Root root = mapper.readValue(new File("test.json"), Root.class);
Client1 c1 = new Client1();
PersonalInfo personalInfo1 = new PersonalInfo();
personalInfo1.setAge(root.getAge());
personalInfo1.setFriendsNames(root.getFriends());
personalInfo1.setName(root.getName());
EducationalInfo educationalInfo1 = new EducationalInfo();
educationalInfo1.setCollege(root.getEducation().getCollege());
educationalInfo1.setGrade(root.getEducation().getGrade());
educationalInfo1.setStudy(root.getEducation().getStudy());
c1.setPersonalInfo(personalInfo1);
c1.setEducationalInfo(educationalInfo1);
mapper.writeValue(new File("client1.json"), c1);
}
}
Inside test.json file :
{
"name": "XYZ",
"age": 24,
"education": {
"college": "ppppp",
"study": "b.tech",
"grade": 6.8
},
"friends": [
"kkkk",
"bbbbbbbbbbb",
"jjjjjj"
],
"dob": "01-08-1990"
}
Inside client1.json file :
{
"personalInfo": {
"name": "XYZ",
"age": 24,
"friendsNames": [
"kkkk",
"bbbbbbbbbbb",
"jjjjjj"
]
},
"educationalInfo": {
"college": "ppppp",
"study": "b.tech",
"grade": 6.8
}
}
Here is the classes which represents your json data:
class Education {
private String college;
private String study;
private float grade;
public String getCollege() {
return college;
}
public void setCollege(String college) {
this.college = college;
}
public String getStudy() {
return study;
}
public void setStudy(String study) {
this.study = study;
}
public float getGrade() {
return grade;
}
public void setGrade(float grade) {
this.grade = grade;
}
}
// root of your base json data
class Root {
private String name;
private int age;
private Education education;
private List<String> friends;
private String dob;
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;
}
public Education getEducation() {
return education;
}
public void setEducation(Education education) {
this.education = education;
}
public List<String> getFriends() {
return friends;
}
public void setFriends(List<String> friends) {
this.friends = friends;
}
public String getDob() {
return dob;
}
public void setDob(String dob) {
this.dob = dob;
}
}
class EducationalInfo {
private String college;
private String study;
private float grade;
public String getCollege() {
return college;
}
public void setCollege(String college) {
this.college = college;
}
public String getStudy() {
return study;
}
public void setStudy(String study) {
this.study = study;
}
public float getGrade() {
return grade;
}
public void setGrade(float grade) {
this.grade = grade;
}
}
// class which represents client 1 json data
class Client1 {
private PersonalInfo personalInfo;
private EducationalInfo educationalInfo;
public PersonalInfo getPersonalInfo() {
return personalInfo;
}
public void setPersonalInfo(PersonalInfo personalInfo) {
this.personalInfo = personalInfo;
}
public EducationalInfo getEducationalInfo() {
return educationalInfo;
}
public void setEducationalInfo(EducationalInfo educationalInfo) {
this.educationalInfo = educationalInfo;
}
}
class PersonalInfo {
private String name;
private int age;
private List<String> friendsNames = null;
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;
}
public List<String> getFriendsNames() {
return friendsNames;
}
public void setFriendsNames(List<String> friendsNames) {
this.friendsNames = friendsNames;
}
}

What about converting it to XML then create some XSLT? it might be much readable and cleaner.

I push full worked example in java into GIT with libs (lombok and jackson)
Template json mapped to object and object to json with different clients.

Your job is to output multilevel JSON data as multiple JSON formats. JSONPath can do this but the process is a hassle.
A simple alternative is to use SPL. SPL is a Java open-source package. You just need three lines of code to get the job done:
enter image description here
SPL offers JDBC driver to be invoked by Java. Just store the above SPL script as jsonparse.splx and invoke it in a Java application as you call a stored procedure:
…
Class.forName("com.esproc.jdbc.InternalDriver");
con= DriverManager.getConnection("jdbc:esproc:local://");
st = con.prepareCall("call jsonparse()");
st.execute();
…

Java doesn't have great templating built in.
But if you want to do a quick an dirty JSON template where you can replace a few values -- especially without all that ugly quote escaping:
{"key":"value"}
You can use single quotes and string replace:
{'key':'VALUE'}.replace("'", """).replace("VALUE", 42)
A few caveats:
This will break if any existing keys or values have single quotes (like O'malley).
It won't replace strings with numbers, boolean, or null
It can't -- by itself -- insert nested arrays or objects (e.g. [] {}) other than as strings.
But with a little bit of of extra work, you can accomplish the 80/20 rule. After that point you'd probably want to look into parsing or generating -- but by then you're not looking for a quick template.

Parsing two JSON files to POJOS, one references the other

I have two files: occupations.json and people.json. The former is just an array of occupations:
[
{ "name": "director", "pay": "100000"},
{ "name": "programmer", "pay": "75000"},
{ "name": "teacher", "pay": "50000"}
]
And the latter an array of a few people along with their occupation:
[
{ "name": "Mary", "occupation": "programmer" },
{ "name": "Jane", "occupation": "director" },
{ "name": "John", "occupation": "teacher" }
]
And these are the corresponding classes:
public class Occupation {
private final String name;
private final int pay;
public String getName() { ... }
public int getPay() { ... }
}
public class Person {
private final String name;
private final Occupation occupation;
public String getName() { ... }
public String getOccupation() { ... }
}
Currently I'm using ObjectMapper.readValue(InputStream, Class) to
unserialize the files. How can I make Person class aware of all existing Occupation objects? I want to select which occupation a person has by using the occupation's name.

add a function to Person.class
public Occupation getOccupation_()
{
// assume you had a static occupations list...
for (Occupation o : occupations)
if (o.name == this.occupation)
return o;
return null;
}

How to convert JSON objects to POJO from Gson

I am trying to convert JSON objects to POJO's with GSON.
JSON String
[
{
"automation_project": {
"user_id": null,
"name": "Untitled Project",
"updated_at": "2015-06-16T19:39:42Z",
"group_id": 764496,
"created_at": "2014-11-23T01:01:59Z",
"id": 16214
}
},
{
"automation_project": {
"user_id": null,
"name": "newintropage",
"updated_at": "2015-06-16T21:20:47Z",
"group_id": 764496,
"created_at": "2015-06-16T20:39:04Z",
"id": 29501
}
}
]
The AutomationProjectsList class used with GSON
public class AutomationProjectsList {
private List<AutomationProject> automationProject = new ArrayList<AutomationProject>();
public List<AutomationProject> getAutomationProject() {
return automationProject;
}
public void setAutomationProject(List<AutomationProject> automationProject) {
this.automationProject = automationProject;
}
#Override
public String toString() {
return "AutomationProjectsList [automationProject=" + automationProject
+ "]";
}}
Automation Project POJO
public class AutomationProject {
private Object userId;
private Integer groupId;
private Integer id;
private String name;
private String updatedAt;
private String createdAt;
public Object getUserId() {
return userId;
}
public void setUserId(Object userId) {
this.userId = userId;
}
public Integer getGroupId() {
return groupId;
}
public void setGroupId(Integer groupId) {
this.groupId = groupId;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getUpdatedAt() {
return updatedAt;
}
public void setUpdatedAt(String updatedAt) {
this.updatedAt = updatedAt;
}
public String getCreatedAt() {
return createdAt;
}
public void setCreatedAt(String createdAt) {
this.createdAt = createdAt;
}}
The code I'm using
JSONArray jsonArray = new JSONArray(response.getEntity(String.class));
for(int i = 0; i < jsonArray.length(); i++){
if(jsonArray.get(i) instanceof JSONObject){
JSONObject jsnObj = (JSONObject)jsonArray.get(i);
AutomationProjectsList obj = new Gson().fromJson(jsnObj.toString(), AutomationProjectsList.class);
System.out.println(obj.getAutomationProject().get(0).getId());
}
}
But it gives an exception :
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.get(ArrayList.java:429)
at br.usp.icmc.teste.ConnectionRestClient.getBrowserStackProjects(ConnectionRestClient.java:74)
at br.usp.icmc.teste.TestePrincipal.main(TestePrincipal.java:9)
Why am I receiving an IndexOutOfBoundsException exception? Where am I wrong?

Your class or your JSON are incorrect. I'd suggest your JSON is.
A JSON matching your POJO class would be:
{
"automationProjects":[
{
"user_id": null,
"name": "Untitled Project",
"updated_at": "2015-06-16T19:39:42Z",
"group_id": 764496,
"created_at": "2014-11-23T01:01:59Z",
"id": 16214
},
{
"user_id": null,
"name": "newintropage",
"updated_at": "2015-06-16T21:20:47Z",
"group_id": 764496,
"created_at": "2015-06-16T20:39:04Z",
"id": 29501
}
]
}
Notice I used the name automationProjects for the list as it makes more sense, so your class would be:
public class AutomationProjectsList {
private List<AutomationProject> automationProjects = new ArrayList<AutomationProject>();
public List<AutomationProject> getAutomationProjects() {
return automationProjects;
}
public void setAutomationProjects(List<AutomationProject> automationProjects) {
this.automationProjects = automationProjects;
}
#Override
public String toString() {
return "AutomationProjectsList [automationProject=" + automationProject
+ "]";
}
}
And finally to convert JSON to AutomationProjectsList object:
AutomationProjectsList projectsList = new Gson().fromJson(jsonArray.toString(), AutomationProjectsList.class);
Then if you want to log each project:
for(AutomationProject project : projectsList.automationProjects){
System.out.println(porject.getId());
}
In conclusion, your code seems to have the fallowing issues:
Do you have a list of lists or just a single list of projects? If the list is just one, why do you iterate jsonArray like its sub-objects are lists themselves?
If you model your class correctly on the JSON then you don't need to iterate the JSON to obtain your objects
The JSON you posted is quite weird and uneasy to use with Gson, is it a requirement or can you edit it as you please?
Hope this helps
EDIT
Since you stated you cannot change the JSON you get, then it gets a little more complex, but everything is up to modelling the classes on the JSON format. So let's start form this JSON:
[
{
"automation_project": {
"user_id": null,
"name": "Untitled Project",
"updated_at": "2015-06-16T19:39:42Z",
"group_id": 764496,
"created_at": "2014-11-23T01:01:59Z",
"id": 16214
}
},
{
"automation_project": {
"user_id": null,
"name": "newintropage",
"updated_at": "2015-06-16T21:20:47Z",
"group_id": 764496,
"created_at": "2015-06-16T20:39:04Z",
"id": 29501
}
}
]
Now, this is quite nasty, but let's see what we have here: we have an unnamed array of objects with a single attribute "automationProject" which is our actual AutomationProject Object. So in terms of structure, it is a list of objects which wrap an actual AutomationProject.
Thus you'll need to get rid of your AutomationProjectList and change it with the more meaningful AutomationProjectWrapper looking as fallows:
public class AutomationProjectsWrapper {
private AutomationProject automation_project = new AutomationProject();
public AutomationProject getAutomationProject() {
return automation_project;
}
public void setAutomationProject(AutomationProject automationProject) {
this.automation_project = automationProject;
}
#Override
public String toString() {
return "AutomationProjectsList [automationProject=" + automation_project
+ "]";
}
}
See this class is equivalent to the JSON Object:
{
"automation_project": {
"user_id": null,
"name": "Untitled Project",
"updated_at": "2015-06-16T19:39:42Z",
"group_id": 764496,
"created_at": "2014-11-23T01:01:59Z",
"id": 16214
}
}
Finally you'll have an array of such wrapper objects as your jsonArray so you can write:
AutomationProjectWrapper[] projectsList = new Gson().fromJson(jsonArray.toString(), AutomationProjectWrapper[].class);
Then to log your objects:
for(AutomationProjectWrapper wrapper : projectsList){
System.out.println(wrapper.getAutomationProject().getId());
}
EDIT 2
Sorry for the mistake, in AutomationProjectWrapper class the AutomationProject field should be named automation_project.
Fixed in code above.

According to your JSON String the value you are trying to access is :
jsonString[i].automation_project.user_id
In your code you have: obj.getAutomationProject().get(0).getId()
I think is should be: obj[i].getAutomationProject().getId()

GSON parsing of nested array

Im having difficulties understanding if GSON can handle this kind of json by default or do I need to implement deserializers for every sub element.
json input
{
"services":[
{
"id": 2,
"name": "Buy"
},
{
"id": 3,
"name": "Sell"
}
]
"status": {
"code": 0,
"message": ""
}
}
The best case result on my part is to have the following class contain all the data
java [ POJO ]
public class Services {
public List<ServiceItem> services;
public Status status;
public class ServiceItem {
public int id;
public String name;
}
public class Status {
public int code;
public String message;
}
}
Is it possible to let GSON the class and the json and just let it work? Or do I need to create deserializers for each sub class?

Correct your json input as follow (you forgot a comma before status field)
{
"services":[
{
"id": 2,
"name": "Buy"
},
{
"id": 3,
"name": "Sell"
}
],
"status": {
"code": 0,
"message": ""
}
}
Then let's consider your classes as follow
public class Services {
public List<ServiceItem> services;
public Status status;
// getters and setters
#Override
public String toString() {
return "["+services.toString()+status.toString()+"]";
}
public class ServiceItem {
public int id;
public String name;
// getters and setters
#Override
public String toString() {
return "("+id+","+name+")";
}
}
public class Status {
public int code;
public String message;
// getters and setters
#Override
public String toString() {
return ",("+code+","+message+")";
}
}
}
If the input is a file jsonInput.json then
Gson gson = new Gson();
Services data = gson.fromJson(new BufferedReader(new FileReader(
"jsonInput.json")), new TypeToken<Services>() {
}.getType());
System.out.println(data);
If the input is a json String jsonInput then
Gson gson = new Gson();
Services data = gson.fromJson(jsonInput, Services.class);
System.out.println(data);
Output:
[[(2,Buy), (3,Sell)],(0,)]