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Jackson exception: Could not resolve type id as a subtype of

I'm trying to parse following JSON string with one field inside. Unfortunatelly still getting exception:
InvalidTypeIdException: Could not resolve type id 'pin' as a subtype of `com.example.dto.AuthorizationRequest`: known type ids = [AuthorizationRequest]
Here is base class:
#JsonTypeInfo(include = JsonTypeInfo.As.WRAPPER_OBJECT ,use = JsonTypeInfo.Id.NAME)
#JsonSubTypes({
#JsonSubTypes.Type(value = AuthorizationRequest.class, name = "AuthorizationRequest")})
public interface IMessage {}
Derived class:
public class AuthorizationRequest implements IMessage {
#JsonProperty( value = "pin", required = true )
private String pin;
public String getPin() {
return pin;
}
public void setPin(String pin) {
this.pin = pin;
}
}
Test:
#Test
void test(){
String request =
"{\n"
+ " \"AuthorizationRequest\": {\n"
+ " \"pin\": \"1234\"\n"
+ " }\n"
+ "}";
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(DeserializationFeature.UNWRAP_ROOT_VALUE, true);
AuthorizationRequest authorizationRequest = null;
try {
authorizationRequest = objectMapper.readValue(request, AuthorizationRequest.class);
} catch (JsonProcessingException e) {
throw new RuntimeException(e);
}
}
What am I missing? I need to use request name as json root element.

You can delete objectMapper.configure(DeserializationFeature.UNWRAP_ROOT_VALUE, true) line. The error is due to the fact that the line unwraps the initial object so escalating of one level at the intern of the json file obtaining the {"pin" : "1234"} json with the ""AuthorizationRequest" label. The JsonTypeInfo.As.WRAPPER_OBJECT annotation indicates to the jackson library to escalate again of one level the json file so obtaining the "1234" string labelled by "pin".The JsonTypeInfo.Id.NAME compares the "pin" string with the names of subclasses and because of it fails causing the issue and the error message.

is it possible to return "if condition satisfies return a list else return an error message" using a java method

I know that in Java a method can return only one return type... But if there is any possiblity to this, kindly let me know. From the below method I am trying to return a list if condition satisfies else i am trying to return an error message.
Here is my code:
#RequestMapping(value = "/getcompanies", method = RequestMethod.POST)
public List<CompanyMaster> getCompanies(#RequestBody UserDetails user) {
String OrgLoginId = user.getOrgLoginId();
String password = user.getuPassword();
String checkLoginId = null;
String uPassword = null;
String encPassword = null;
String loginId = null;
String checkAuthorized = null;
// String loginId=userService.getLoginId(OrgLoginId);
List<Object[]> CheckIdPassword = userService.checkLoginId(OrgLoginId);
List<Object[]> results = CheckIdPassword;
for (Object[] obj : results) {
checkLoginId = obj[0].toString();
if (null == obj[1]) {
uPassword = "";
} else {
uPassword = obj[1].toString();
}
loginId = obj[2].toString();
}
checkAuthorized = loginId.substring(0, 3);
if (null != password) {
MD5 md5 = new MD5();
encPassword = md5.getPassword(password);
}
if (checkLoginId == null) {
return "Incorrect loginId..Please enter valid loginId";
} else if (encPassword.equals(uPassword)) {
if (checkAuthorized.equals("STE")) {
List<CompanyMaster> companyList = userService.getCompanyList(OrgLoginId);
return companyList;
} else {
return "You are not Authorized";
}
} else {
return "Incorrect Password";
}

Yes its possible, create a custom Exception say 'MyAppException' and throw that exception with the error message you want.
Write your logic in a try{}catch block and throw the exception in catch so that the response has the error message
public List<CompanyMaster> getCompanies(#RequestBody UserDetails user) throws MyAppppException
{
try
{
//your logic which throws error
return companyList;
}
catch( final MyAppException we )
{
throw new MyAppException("User not found", HttpStatus.NOT_FOUND);
}
}
Refer this link
https://www.codejava.net/java-core/exception/how-to-create-custom-exceptions-in-java

You can achieve this by creating a new presenter Class which contains List and status of type String and change the return type of getCompanies method to presenter class like
public CompaniesPresenter getCompanies()
And your CompaniesPresenter class should look like
public class CompaniesPresenter {
private List<CompanyMaster> companyMaster;
private string status;
//default constructor
public CompaniesPresenter(){
}
//parameterized constructor to return only string in exception case
public CompaniesPresenter(Stirng status){
this.status = status;
}
//parametirized constructor to return success case
public CompaniesPresenter(List<CompanyMaster> companyMaster, Stirng status){
this.companyMaster = companyMaster;
this.status = status;
}
//getters and setters
}
This is how your updated method lokks like
#RequestMapping(value = "/getcompanies", method = RequestMethod.POST)
public CompaniesPresenter getCompanies(#RequestBody UserDetails user) {
String OrgLoginId = user.getOrgLoginId();
String password = user.getuPassword();
String checkLoginId = null;
String uPassword = null;
String encPassword = null;
String loginId = null;
String checkAuthorized = null;
// String loginId=userService.getLoginId(OrgLoginId);
List<Object[]> CheckIdPassword = userService.checkLoginId(OrgLoginId);
List<Object[]> results = CheckIdPassword;
for (Object[] obj : results) {
checkLoginId = obj[0].toString();
if (null == obj[1]) {
uPassword = "";
} else {
uPassword = obj[1].toString();
}
loginId = obj[2].toString();
}
checkAuthorized = loginId.substring(0, 3);
if (null != password) {
MD5 md5 = new MD5();
encPassword = md5.getPassword(password);
}
if (checkLoginId == null) {
return new CompaniesPresenter("Incorrect loginId..Please enter valid loginId");
} else if (encPassword.equals(uPassword)) {
if (checkAuthorized.equals("STE")) {
List<CompanyMaster> companyList = userService.getCompanyList(OrgLoginId);
return new CompaniesPresenter(companyList,"success");
} else {
return new CompaniesPresenter("You are not Authorized");
}
} else {
return new CompaniesPresenter("Incorrect Password");
}
This is not tested please make sure for any compilation errors

vavr's Either class would be a good choice.

The usage of custom exception is most reasonable solution. However, creating custom exception for just one case is not ideal always.
Another solution is to return empty List from your method, check if the List is empty in your servlet (or wherever you are invoking this method from), and show error message there.
It seems like you want to return multiple error messages for different cases. In this case, custom exception is recommended solution. If you don't like custom exceptions, you can return List<Object> and populate error message as the first element in the list. In the place where this List is obtained, check if the first element is instanceOf String or CompanyMaster. Based on what it is, you can perform your operations. This is a weird but possible solution (only if you don't like custom exceptions).

You need to understand the problem first. You are mixing two things here, first authorization, does the user has correct privileges to get company details, second giving the company details itself. Let's understand the first problem when a user tries to access "/getcompanies" endpoint will you let him in if does not have access, in REST world your security model should take care of it. I would use spring security to achieve this. My recommendation would be to explore on "interceptor" and solve the problem of invalid user. This will make your other problem easy as your "/getcompanies" endpoint can focus only on getting the details and return it (SRP).

How to print out a list item based on its status?

I'm creating an eAuction system and I have a method for browsing auctions. Each auction has a status (OPEN or CLOSED) and I want the browseAuctions method to only print out auctions that are opened.
I've tried a number of if statements and it always keeps printing out every single auction.
The following code is a few things I've hardcoded to test the system
public List<Auction> auctionSystem() throws Exception {
List<Auction> auctions = new LinkedList<Auction>();
auctions.add(new Auction (35.50, 75.50, 40.00, users.get(3), LocalDateTime.now().minusSeconds(60), "Xbox", users.get(1), Status.OPEN));
auctions.add(new Auction (27.00, 42.00, 32.00, users.get(2), LocalDateTime.now().plusSeconds(10), "PS3", users.get(1), Status.OPEN));
auctions.add(new Auction (19.00, 21.00, 50.00, users.get(2), LocalDateTime.now().minusSeconds(1), "iPhone", users.get(1), Status.CLOSED));
return auctions;
}
This is the Auction class constructor:
public Auction (double startPrice, double reservePrice, double currentBid, User highestBidder, LocalDateTime closeDate, String item, User seller, Status status) throws Exception {
if (closeDate.isBefore(LocalDateTime.now().plusDays(7))) {
this.startPrice = startPrice;
this.reservePrice = reservePrice;
this.closeDate = closeDate;
this.item = item;
this.highestBidder = highestBidder;
this.currentBid = currentBid;
this.seller = seller;
UP = currentBid * 0.20;
LOW = currentBid * 0.10;
} else {
throw new Exception ("CloseDate error: " + closeDate.format(formatter));
}
}
This is the Status class:
public enum Status {
OPEN, CLOSED
}
This is the method inside the Auction class to browse auctions:
public void browseAuctions () {
System.out.println("-----All Auctions-----");
for (Auction a : auctions) {
if (a.status.equals(Status.OPEN)){
System.out.println("Item: " + a.getItem());
System.out.println("Current Bid: " + "£" + a.getCurrentBid());
System.out.println("Close Date: " + a.getCloseDate());
}
}
}
}

The status is ignored in the constructor, therefore all the Auction instances shall be not be qualified according to the condition in the loop. I wonder all pass and the only explanation is that the Status.OPEN is set by default, it means you have the following declaration in the code:
private Status status = Status.OPEN;
Since it is missing in the constructor, it is not set to a new passed value. These are problems with mutable fields, so I suggest you declare them final and resolve a default value with a secondary constructor:
private final Status status;
// the rest
public Auction (double sPrice, double rPrice, double currentBid,
User highestBidder, LocalDateTime closeDate, String item, User seller)
{
this(sPrice, rPrice, currentBid, highestBidder, closeDate, item, seller, Status.OPEN)
}
Anyway, to fix your issue, complete the constructor with:
this.status = status;

Oracle Berkeley DB Java Edition - Secondary key unicity

I have a simple entity class and it is supposed to include unique names on it.
#Entity
class Package {
#PrimaryKey(sequence = "ID")
public Long id;
#SecondaryKey(relate = Relationship.ONE_TO_ONE)
public String name;
private Package() {}
public Package(String name) { this.name = name; }
#Override
public String toString() { return id + " : " + name; }
}
I want to use deferred writing option because of extensive modification. Here is the test i tried and its output.
final String dbfilename = "test01";
new File(dbfilename).mkdirs();
EnvironmentConfig config = new EnvironmentConfig().setAllowCreate(true);
Environment environment = new Environment(new File(dbfilename), config);
StoreConfig storeConfig = new StoreConfig().setAllowCreate(true).setDeferredWrite(true);
EntityStore store = new EntityStore(environment, "", storeConfig);
PrimaryIndex<Long, Package> primaryIndex = store.getPrimaryIndex(Long.class, Package.class);
try {
primaryIndex.put(new Package("package01")); // will be put.
primaryIndex.put(new Package("package01")); // throws exception.
} catch (UniqueConstraintException ex) {
System.out.println(ex.getMessage());
}
store.sync(); // flush them all
// expecting to find one element
SortedMap<Long,Package> sortedMap = primaryIndex.sortedMap();
for (Package entity : sortedMap.values()) {
System.out.println(entity);
}
Output
(JE 5.0.73) Unique secondary key is already present
1 : package01
2 : package01
So my question is that even if it throws exception while putting second package, why does it lists two packages. Any way to avoid this without using transactions?
Thanks.

Where did I go wrong in this code?

A few of my classes aren't passing automated tests. Unfortunately, said tests do not provide any useful information about why they failed. Here is my code for a couple of the classes. I'd really appreciate it if you could tell me where I went wrong. The comments should explain what each method is supposed to do.
public class CellPhone {
protected String ownerName;
public CellPhone(String owner) {
ownerName = owner;
}
public String receiveCall(CellPhone sender) {
// returns a String of the form:
// owner's name " is receiving a call from " sender's name
String receivingCall = ownerName + " is receiving a call from " + sender;
return receivingCall;
}
public String call(CellPhone receiver) {
// returns a String by using the receiver to invoke receiveCall
// while passing in the current phone
String invokingReceiveCall = receiver.receiveCall(receiver);
return invokingReceiveCall;
}
}
public class TextMessagingPhone extends CellPhone {
private int availMessages;
public TextMessagingPhone(String owner, int messageLimit) {
// invokes the superclass constructor
super(owner);
// sets the new instance variable
availMessages = messageLimit;
}
public TextMessagingPhone(String owner) {
// invokes the other constructor of this class with 15 as the message limit
this(owner, 15);
}
public String receiveText(TextMessagingPhone sender, String message) {
// decreases the number of messages available to send
availMessages--;
// returns a String of the form:
// owner's name " has received TEXT from " sender's name ":" message
String receivedText = ownerName + " has received TEXT from " + sender + ":" + message;
return receivedText;
}
public String sendText(TextMessagingPhone receiver, String message) {
// decreases the number of messages available to send
availMessages--;
// returns a String by using the receiver to invoke receiveText
// while passing in the current phone and the message
String invokingReceiveText = receiver.receiveText(receiver, message);
return invokingReceiveText;
}
}

When a phone makes a call, it passes the receiver as a parameter, so the receiver thinks it is receiving from itself. Also it never gets the name from the passed sender. Try:
public String receiveCall(CellPhone sender) {
// returns a String of the form:
// owner's name " is receiving a call from " sender's name
String receivingCall = ownerName + " is receiving a call from " + sender.getName();
return receivingCall;
}
public String call(CellPhone receiver) {
// returns a String by using the receiver to invoke receiveCall
// while passing in the current phone
String invokingReceiveCall = receiver.receiveCall(this);
return invokingReceiveCall;
}
public String getName() {
return ownerName;
}

public CellPhone(String owner) {
}
You don't assign anything to ownerName...
public CellPhone(String owner) {
ownerName = owner;
}

Check this
String receivingCall = ownerName + " is receiving a call from " + sender;
You are using "sender" which is an object in the string expression. Using sender.ownerName after making it public or defining getOwnerName and using it should work. This same mistake is repeated couple more times!