Question

这是我的代码

import java.util.Scanner;
public class Input {
    static class General_Inputs{
        static int Num_Of_Ppes;
        static int Num_Of_States;
        static int Num_Of_Analysis_Years;
        static int Number_Decision_Variables;
        static int Num_objectives;
        static int Num_Constraints;
        static int[] Num_Alt_Decision_variable=new int[Number_Decision_Variables];  
    }
public static double[][] Get_Inputs(){
    Scanner State_Vector=new Scanner(System.in);
    System.out.println("Enter the number of Decision_Variables");
    General_Inputs.Number_Decision_Variables=State_Vector.nextInt();
    for(int Num=0;Num<General_Inputs.Number_Decision_Variables;Num++){
        System.out.println("Enter the number of Alternatives for Decision Variable "+(Num+1));
        General_Inputs.Num_Alt_Decision_variable[Num]=State_Vector.nextInt();
    }
    State_Vector.close();
    return Current_Cond_State_Cof_lngth;
}
public static void main(String args[]){
    double[][] input=Input.Get_Inputs();

输入如下：输入Decision_Variables的数量 3 输入决策变量1的备选数量 2 这应该去三次，但它停在第一个决策变量并给出以下错误我不知道问题出在哪里。我明白这个错误意味着数组“Num_Alt_Decision_variable”的大小为零，但为什么我在上面定义了这个数组，我真的试图搜索很多但找不到原因任何帮助都非常感谢提前感谢。< / p>

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
    at Input.Get_Inputs(Input.java:48)
    at Input.main(Input.java:66)

Answer 1

    static int Number_Decision_Variables; // this is 0 here
    static int Num_objectives;
    static int Num_Constraints;

    // and it's still 0 here.
    static int[] Num_Alt_Decision_variable=new int[Number_Decision_Variables];

在声明Num_Alt_Decision_variable时，Number_Decision_Variables为0。所以你的数组大小为0，这是一个不可用的数组。我建议你用非0号码初始化它。

在这行之后>初始化数组：

General_Inputs.Number_Decision_Variables=State_Vector.nextInt();

获得Number_Decision_Variables变量的实际值后。

另外，您需要学习并使用Java naming conventions。变量名都应以较低的字母开头，而类名以大写字母开头。

Answer 2

这是我能解决的答案

import java.util.Scanner;
public class Input {
    static class General_Inputs{
        static int Num_Of_Ppes;
        static int Num_Of_States;
        static int Num_Of_Analysis_Years;
        static int Number_Decision_Variables;
        static int Num_objectives;
        static int Num_Constraints;
        static int[] Num_Alt_Decision_variable;  
    }
public static double[][] Get_Inputs(){
    Scanner State_Vector=new Scanner(System.in);
    System.out.println("Enter the number of Decision_Variables");
    General_Inputs.Number_Decision_Variables=State_Vector.nextInt();
General_Inputs.Num_Alt_Decision_variable=new int[General_Inputs.Number_Decision_Variables]
    for(int Num=0;Num<General_Inputs.Number_Decision_Variables;Num++){
        System.out.println("Enter the number of Alternatives for Decision Variable "+(Num+1));
        General_Inputs.Num_Alt_Decision_variable[Num]=State_Vector.nextInt();
    }
    State_Vector.close();
    return Current_Cond_State_Cof_lngth;
}
public static void main(String args[]){
    double[][] input=Input.Get_Inputs();

不知道为什么我有这个错误线程“main”中的异常java.lang.ArrayIndexOutOfBoundsException：0

2 个答案: