[FIXED] Cannot construct instance of `class name` (although at least on Creator exists)

Issue

I have the following class, which I am using as a request payload :

public class SampleRequest {

    private String fromDate;
    private String toDate;

    // Getters and setters removed for brevity.
}

I am trying to use it with this resource below (just trying to print it to screen to see things happen) :

@PostMapping("/getBySignatureOne")
public ResponseEntity<?> getRequestInfo(@Valid @RequestBody SampleRequest signatureOneRequest) {

    System.out.println(signatureOneRequest.getToDate);
    System.out.println(signatureOneRequest.getFromDate);
}

This is the JSON request I send up :

{
    "fromDate":"2019-03-09",
    "toDate":"2019-03-10"
}

This is the error I get :

Resolved [org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Cannot construct instance of `com.test.app.payload.SampleRequest` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('fromDate'); nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `com.test.app.payload.SampleRequest` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('fromDate')
 at [Source: (PushbackInputStream); line: 1, column: 2]]

I'd love to know what's wrong here, I suspect its an issue with constructors, or that I am missing some annotation somewhere, but I am honestly unsure of where I have gone wrong.

Solution

You need a constructor with all parameters:

public SampleRequest(String fromDate, String toDate) {

    this.fromDate = fromDate;
    this.toDate = toDate;

}

Or using @AllArgsConstructor or @Data from lombok.

Answered By - Andronicus
Answer Checked By - Cary Denson (JavaFixing Admin)