Java Spring RestTemplate从api获取1个对象

Question

我一直遇到一个问题，我似乎在任何地方都找不到解决方案。我有一个api，它用一个对象“员工身份认证响应”进行响应。这是一个单独的对象，里面有用户的信息，比如他的名字和角色。只能有1个响应，所以它总是发送1个。

这是rest api控制器中的代码：

@GetMapping("/authenticate")
public EmployeeAuthenticatedResponse getAuthenticated(@RequestHeader(value = "email") String requestMail, @RequestHeader(value = "password") String requestPassword){
    return employeeService.signin(requestMail, requestPassword);
}

我用这个来试着找回它:

public class LoginController {
    @FXML
    private Label errorText;
    @FXML
    private TextField email;
    @FXML
    private PasswordField password;

    @FXML
    protected void login(ActionEvent event) throws NoSuchAlgorithmException {
        if(email != null && email.getText() != "" && password != null && password.getText() != ""){

            //Hash password before sending it out(This is just extra for during the connection, the server hashed it again with Bcrypt)
            MessageDigest md = MessageDigest.getInstance("SHA-256");
            byte[] digest = md.digest(password.getText().getBytes(StandardCharsets.UTF_8));
            String passwordHash = String.format("%064x", new BigInteger(1,digest));

            //Initiate Spring stuff
            RestTemplate restTemplate = new RestTemplate();
            HttpHeaders headers = new HttpHeaders();

            //maak headers
            headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
            headers.setContentType(MediaType.APPLICATION_JSON);
            headers.add("user-agent", "My app");
            headers.add("email", email.getText());
            headers.add("password", passwordHash);
            HttpEntity<?> entity = new HttpEntity<Object>("parameters", headers);

            //Send it away and retrieve
            ResponseEntity<EmployeeAuthenticatedResponse> loginResponse = restTemplate.exchange("http://localhost:8080/employee/authenticate", HttpMethod.GET, entity, EmployeeAuthenticatedResponse.class);

            //If else stuffs
            if(loginResponse.getStatusCode() == HttpStatus.OK){
                errorText.setText("it works");
            } else if(loginResponse.getStatusCode() == HttpStatus.FORBIDDEN) {
                errorText.setText("wrong password");
            } else if(loginResponse.getStatusCode() == HttpStatus.REQUEST_TIMEOUT){
                errorText.setText("error");
            }
        }
    }

}

现在，当我尝试使用它时，我得到一些警告和一个错误。第一次“警告”

18:04:56.170 [JavaFX Application Thread] WARN org.springframework.http.converter.json.MappingJackson2HttpMessageConverter - Failed to evaluate Jackson deserialization for type [[simple type, class link.to.class.DTO.EmployeeAuthenticatedResponse]]
java.lang.reflect.InaccessibleObjectException: Unable to make public link.to.class.EmployeeAuthenticatedResponse() accessible: module link.to.class does not "exports link.to.class.DTO" to unnamed module @13f33d2d

然后它提供了一些额外的信息：

18:04:56.171 [JavaFX Application Thread] DEBUG org.springframework.web.client.RestTemplate - Accept=[]
18:04:56.173 [JavaFX Application Thread] DEBUG org.springframework.web.client.RestTemplate - Writing [parameters] as "application/json"
18:04:56.683 [JavaFX Application Thread] DEBUG org.springframework.web.client.RestTemplate - Response 200 OK

然后它为类型警告两次给出了相同的失败求值Jackson反序列化，然后我得到了一个无法提取响应：没有为响应类型error/exception找到合适的HttpMessageConverter，这就是它结束的地方。

当我在EmployeeAuthenticatedResponse后面添加[]时，我已经查找了很多关于Stack溢出和其他站点的信息，比如：

ResponseEntity<EmployeeAuthenticatedResponse[]> loginResponse = restTemplate.exchange("http://localhost:8080/employee/authenticate", HttpMethod.GET, entity, EmployeeAuthenticatedResponse[].class);

我直接进入异常，没有警告。这让我认为问题是，当像这样使用RestTemplate时，我需要一个列表作为响应，而不是一个对象，但是我如何获得一个实体呢？我在网上能找到的一切都是关于消费列表的。

EmployeeAuthenticedResponse 类：

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;

@JsonIgnoreProperties(ignoreUnknown = true)
public class EmployeeAuthenticatedResponse {
    private int employeeId;
    private String employeeFirstName;
    private String employeeLastName;
    private int employeeDarkMode;
    private int employeeRoleId;
    private String employeeRoleName;
    private int employeePermissionSales;
    private int employeePermissionSending;
    private int employeePermissionManager;
    private int employeePermissionProductManagement;
    private String JWTToken;

//Getters and setters

}

约翰逊：

{
    "employeeId": 1,
    "employeeFirstName": "TestFname",
    "employeeLastName": "TestLname",
    "employeeDarkMode": 1,
    "employeeRoleId": 1,
    "employeeRoleName": "owner",
    "employeePermissionSales": 1,
    "employeePermissionSending": 1,
    "employeePermissionManager": 1,
    "employeePermissionProductManagement": 1,
    "jwttoken": "JWTTOKEN"
}

Module-info.java：

module com.windsoftware.kassa.windkassadesktop {
    requires javafx.controls;
    requires javafx.fxml;
    requires javafx.web;

    requires org.controlsfx.controls;
    requires com.dlsc.formsfx;
    requires validatorfx;
    requires org.kordamp.ikonli.javafx;
    requires org.kordamp.bootstrapfx.core;
    requires eu.hansolo.tilesfx;
    requires spring.boot;
    requires spring.web;
    requires com.fasterxml.jackson.databind;
    requires com.fasterxml.jackson.annotation;
    requires spring.boot.autoconfigure;

    opens link.to.class to javafx.fxml;
    exports link.to.class;
    exports link.to.class.controllers;
    opens link.to.class.controllers to javafx.fxml;
}

Answer 1

该问题可能与对象deSerialize雇员身份验证响应

ResponseEntity<String> loginResponse = restTemplate.exchange(URL, HttpMethod.GET, request, String.class);

或

String loginResponse = restTemplate.exchange(URL, HttpMethod.GET, request, String.class).getBody();

使用这个并记录登录响应，然后你会得到关于对象问题的想法

Answer 2

由于您使用的是Java16，您必须在模块设置中导出DTO包，以便其余模板中的jackson对象映射器能够访问您的DTO类及其字段以进行反射

Module-info.java：

module com.windsoftware.kassa.windkassadesktop {
    requires javafx.controls;
    requires javafx.fxml;
    requires javafx.web;

    requires org.controlsfx.controls;
    requires com.dlsc.formsfx;
    requires validatorfx;
    requires org.kordamp.ikonli.javafx;
    requires org.kordamp.bootstrapfx.core;
    requires eu.hansolo.tilesfx;
    requires spring.boot;
    requires spring.web;
    requires com.fasterxml.jackson.databind;
    requires com.fasterxml.jackson.annotation;
    requires spring.boot.autoconfigure;

    opens link.to.class to javafx.fxml;
    exports link.to.class;
    exports link.to.class.controllers;
    exports link.to.class.DTO;
    opens link.to.class.controllers to javafx.fxml;
}