java - 将请求参数转换为Class对象

Question

我有两个 POJO 类。

类 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 类是 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 REST Controller ，用于提供车辆信息(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 将创建车辆对象并填充类型和制造商的值。但是如果我提供了engineId的值，那么Spring就无法创建Engine对象，使得vehicle.getEngine().getEngineId() != null

如果我调用我的休息服务，有什么方法可以使用吗:

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

然后使用具有engineId值的Engine创建车辆？

Answer 1

您可以这样获取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:

1. 确保您的类实现可序列化
2. 对于从 Java 到 Javascript 转换时不确定的字段(反之亦然)，例如 Date 变量，您必须正确设置 JsonSerializer 类

更新:您想从请求中获取对象，因此:

    @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");
    });