400错误请求尝试POST到Spring端点

Question

Trying to post this to my Spring api

{
    "test1":"test1",
    "test2":"test2",
    "test3":"test3"
}

But i keep getting a 400 Bad Request response.

Controller looks like this:

@RestController
@RequestMapping("/rest/api")
public class DokumentController {

    @PostMapping(value = "/test", consumes = MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity test(@RequestBody TestDTO body) {
        System.out.println(body.getTest1());
        return ResponseEntity.ok().build();
    }
}

TestDTO looks like this:

public class TestDTO {
    private String test1;
    private String test2;
    private String test3;

    TestDTO(String test1, String test2, String test3) {
        this.test1 = test1
        this.test2 = test2
        this.test3 = test3
    }

    public String getTest1() {
        return test1;
    }

    public void setTest1(String test1) {
        this.test1 = test1;
    }

    //And so on..

}

Can someone tell me what I'm doing wrong here?

Answer 1

You have to create a constructor with no arguments in your DTO class:

public class TestDTO {
    private String test1;
    private String test2;
    private String test3;

    //Default no argument constructor
    TestDTO() {
    }

    TestDTO(String test1, String test2, String test3) {
        this.test1 = test1
        this.test2 = test2
        this.test3 = test3
    }

    public String getTest1() {
        return test1;
    }

    public void setTest1(String test1) {
        this.test1 = test1;
    }

    //And so on..

}

The Jackson Framework creates the class first and uses reflection to set the values.