类中的Java自定义异常处理

Question

我使用netbeans创建了这个异常类：

public class VehicleException extends Exception{
    private String matricula;
    private Calendar dataMatricula;
    private ModelVehicle model;

    private int causa;

        public VehicleException(int causa, Object valor) throws Exception {
        this.causa = causa;
        switch (causa) {
            case 1:
                dataMatricula = (Calendar) valor;
                break;
            case 2:
                matricula = (String) valor;
                break;
            case 3:
                model = (ModelVehicle) valor;
                break;

            default:
                throw new Exception("Utilització errònia en construir VehicleException. Causa: " + causa);
        }
    }

         @Override
    public String getMessage() {
        switch (causa) {
            case 1:
                return "dataMatricula erroni: " + dataMatricula + " Ha de contenir valor";
            case 2:
                return "matricula erroni: " + matricula + " Ha de contenir valor";
            case 3:
                return "Model erroni: " + model + " Ha de contenir valor";
            default:
                return "";
        }
    }

public class Vehicle implements Comparable<Vehicle> {

    private String matricula;
    private ModelVehicle model;
    private Calendar dataMatricula;


     public Vehicle(String matricula, ModelVehicle model, Calendar dataMatricula) throws VehicleException {
        setMatricula(matricula);
        setDataMatricula(dataMatricula);
        setModelVehicle(model);


    }


     public String getMatricula(){
         return matricula;
     }

     public ModelVehicle getModelVehicle(){
         return model;
     }
     public Calendar getDataMatricula(){
         return dataMatricula;
     }


      public final void setMatricula(String matricula) throws VehicleException {
        if (matricula == null || matricula.compareTo("") == 0) {
            throw new VehicleException(2,matricula);
        }
        this.matricula = matricula;
    }

      public void setModelVehicle(ModelVehicle model) throws VehicleException{
          if(model == null){
             throw new VehicleException(3,model);
          }
          else {
              this.model = model;
          }
      }

      public void setDataMatricula(Calendar c) throws VehicleException{
          if(c == null){
             throw new VehicleException(1,c);
          }
          this.dataMatricula = c;
      }

当我尝试编译时，问题变得更加突出，在setter方法中，我得到以下消息：

错误：未报告异常异常；必须捕获或声明被抛出抛出新车辆异常（2,matricula）；C:\users\ivan\desktop\examen isidrer\m03-uf5\exmaenm03uf5\src\info\infomila\vehicle.java:55:错误：未报告的异常异常；必须捕获或声明要抛出抛出新VehicleException(3，model)；C:\users\ivan\desktop\examen isidrer\m03-uf5\exmaenm03uf5\src\info\infomila\vehicle.java:64:错误：未报告的异常异常；必须捕获或声明要抛出抛出new VehicleException（1,c）；

我不是很理解为什么会发生这种情况，因为setter方法有一个“throws vehicleexception”。

Answer 1

VehicleException的构造函数本身可以引发异常：

public VehicleException(int causa, Object valor) throws Exception {
                                                 ^^^^^^^^^^^^^^^^

这意味着您的调用范围需要从构造函数处理/重新抛出该异常，或者您可以选择抑制该异常而不是抛出它。

default:
    super.addSuppressed(new Exception("Utilització errònia en construir VehicleException. Causa: " + causa));