java方法和构造函数不能应用

Question

我打算制作一个程序，询问用户他们要在车库中存储多少车辆，并让用户放置车辆的信息并将其存储在数组中，这里是代码：

public class Main { 
    static class veh { 
     int roda; 
     String warna; 
     String merk; 

     public veh(int roda, String warna, String merk){ 
      this.roda = roda; 
      this.warna = warna; 
      this.merk = merk; 
     } 
     private void setRoda(){ 
     } 
     private void setWarna(){ 
     } 
     private void setMerk(){ 
     } 
    } 

    public static void main(String[] args) { 
     Scanner in = new Scanner(System.in); 
     System.out.print("Pemilik Garasi\t: "); 
     String nama = in.nextLine(); 
     System.out.print("NIM\t\t\t\t: "); 
     String nim = in.next(); 
     System.out.print("Kelas\t\t\t: "); 
     String kls = in.next(); 
     System.out.print("Masukkan Luas Garasi\t:"); 
     int luas = in.nextInt(); 
     veh[] data = new veh[luas]; 
     System.out.println("============================"); 

     for (int i = 0; i < luas; i++) { 
      veh vehicle = new veh(); 
      System.out.println("Masukkan Data Kendaraan Ke " + (i + 1)); 
      System.out.print("Jumlah Roda\t: "); 
      vehicle.setRoda(in.nextInt()); 
      System.out.print("Warna\t\t: "); 
      vehicle.setWarna(in.next()); 
      System.out.print("Merk\t\t: "); 
      vehicle.setMerk(in.next()); 
      data[i] = vehicle; 
     } 

     System.out.println("====== GARASI PRIBADI ======"); 
     System.out.println("Milik \t: " + nama); 
     System.out.println("NIM \t: " + nim); 
     System.out.println("Kelas \t: " + kls); 
     System.out.println("============================"); 
     for (int i = 0; i < luas; i++) { 
      System.out.println("Kendaraan Ke " + (i + 1)); 
      System.out.println("Jumlah Roda\t : " + data[i].roda); 
      System.out.println("Warna\t\t : " + data[i].warna); 
      System.out.println("Merk\t\t : " + data[i].merk); 
      System.out.println("--------------------------"); 
     } 
    } 
} 

当我编译它，我在此行得到了一个错误：

veh vehicle = new veh(); 
vehicle.setRoda(in.nextInt()); 
vehicle.setWarna(in.next()); 
vehicle.setMerk(in.next()); 

我真的不知道getter/setter方法是如何工作的，我是用Java编程语言新，做我写错了什么？

Answer 1

1. 要调用不带参数的构造中，为了做到这一点 你需要重载它，因此，声明另一个构造函数没有参数。

2. setter和getters或封装的概念通常是防止直接访问变量本身，并使用函数修改或获取它们的值。你的二传手需要一个参数并设置你想要的值 并且吸气机返回值。

   public class Main { 
       static class veh { 
        private int roda; 
        private String warna; 
        private String merk; 
   
        public veh(){} 
   
        public veh(int roda, String warna, String merk){ 
         this.roda = roda; 
         this.warna = warna; 
         this.merk = merk; 
        } 
        public void setRoda(int newRoda){ 
         roda = newRoda; 
        } 
   
        public void setWarna(String newWarna){ 
         warna = newWarna; 
        } 
        public void setMerk(String newMerk){ 
         merk = newMerk; 
        } 
        public void getRoda(){ 
         return roda; 
        } 
   
        public void getWarna(){ 
         retun warna; 
        } 
        public void getMerk(){ 
         return merk; 
        } 
   
       }