将请求参数转换为 Class 对象

Question

我有两个 POJO classes.

Class 1 是 Engine.java:

private String engineId;

public String getEngineId(){
  return this.engineId;
}   

public void setEngineId(String engineId){
  this.engineId = engineId;
}

第二个 POJO class 是 Vehicle.java:

private String type;
private String manufacturer;
private Engine engine;

public String getType() {
   return type;
} 

public void setType(String type) {
    this.type = type;
} 

public String getManufacturer() {
     return manufacturer;
} 

public void setManufacturer(String manufacturer) {
     this.manufacturer = manufacturer;
}  

public Engine getEngine() {
     return engine;
} 

public void setEngine(Engine engine) {
    this.engine = engine;
}

我有一个用于提供车辆信息的 REST 控制器 (RequestMethod.GET):

@RequestMapping(method = RequestMethod.GET)
public Vehicle getVechileDetails(Vehicle inputVehicle){
   Vehicle vehicle = new Vehicle();
    // some processing
    return vehicle;
}

当我点击此服务并提供请求参数作为类型或制造商时，Spring 会创建 Vehicle 对象并填充类型和制造商的值。但是，如果我提供 engineId 的值，则 Spring 无法创建 Engine 对象，使得 vehicle.getEngine().getEngineId() != null

有没有什么方法可以让我像这样调用我的 Rest 服务：

http://localhost:8080/Controller/getVehicleDetails?engineId=12345

然后使用值为 engineId 的 Engine 创建 Vehicle ?

Answer 1

你可以这样获取vehicleId（包含ResponseEntity结构）：

    @RequestMapping(value = "/Controller/getVehicleDetails", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
    public
    @ResponseBody
    ResponseEntity<AjaxResponse> controller(@RequestParam(value = "engineId") Long engineId) {
        //Do whatever you want with the engineId
        return new ResponseEntity<AjaxResponse>(new AjaxResponse("Success"), HttpStatus.OK);
    }

但是，对于 POJO，我必须警告两件事：

确保您的 classes 实现 Serializable
对于从 Java 转换为 Java 脚本时不确定的字段，反之亦然，例如 Date 变量，您必须设置 JsonSerializer class正确

更新： 你想从请求中获取对象，所以：

    @RequestMapping(value = "/Controller/getVehicleDetails", method = RequestMethod.POST, produces = MediaType.APPLICATION_JSON_VALUE, , consumes = MediaType.APPLICATION_JSON_VALUE)
    public
    @ResponseBody
    ResponseEntity<AjaxResponse> controller(@RequestBody Vehicle vehicle) {
        //vehicle.getEngine().getEngineId()
        return new ResponseEntity<AjaxResponse>(new AjaxResponse("Success"), HttpStatus.OK);
    }

POJOS：

    public class Engine implements Serializable {
        //...
    }

    public class Vehicle implements Serializable {
        private Engine engine;
    }

JS 端：

    var vehicle = {
        engine: {id: 123}//,
        //...
    }
    //via angularjs:
    $http.post("http://localhost:8080/Controller/getVehicleDetails", vehicle).success(function(response) {
        console.log("success");
    });

Answer 2

这里你可以参考，其中请求体有JSON转换为对象参见：For references

@RequestMapping(value = EmpRestURIConstants.CREATE_EMP, method = RequestMethod.POST)
    public @ResponseBody Employee createEmployee(@RequestBody Employee emp) {
        logger.info("Start createEmployee.");
        emp.setCreatedDate(new Date());
        empData.put(emp.getId(), emp);
        return emp;
    }

将请求参数转换为 Class 对象

Converting request parameters to the Class object

java

spring

spring-rest