java - 如何在同一级别的 if 语句中分配/访问变量

Question

所以，我需要访问我在最后一个 if 语句中的 if 语句中分配的变量。我是 Java 初学者，感谢任何帮助:)

这是我的编译错误。

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
The local variable a may not have been initialized
The local variable b may not have been initialized
The local variable c may not have been initialized
The local variable d may not have been initialized
The local variable e may not have been initialized

这是我的代码。我需要根据已经经过的迭代次数分配某个变量，并在最后一次迭代分配变量后访问这些变量。

public static void main(String[] args){
    String a;
    String b;
    String c;
    String d;
    String e;
    Scanner s = new Scanner(System.in);

for( int loop = 1; loop <= 6; loop++ ){
    if(loop == 1){
        System.out.println("Please input a grade.");
        a = s.nextLine();
        System.out.println("You said,"+a);
        continue;
        }
    if(loop == 2){
        System.out.println("Please input a grade.");;
        b = s.nextLine();
        System.out.println("You said,"+b);
        continue;
    }
    if(loop == 3){
        System.out.println("Please input a grade.");
        c = s.nextLine();
        System.out.println("You said," +c);
        continue;
    }
    if(loop == 4){
        System.out.println("Please input a grade.");
        d = s.nextLine();
        System.out.println("You said," +d);
        continue;
    }
    if(loop == 5){
        System.out.println("Please input a grade.");
        e = s.nextLine();
        System.out.println("You said," +e);
        continue;
    }
    if(loop == 6){
        System.out.println("Grade 1."+a);
        System.out.println("Grade 1."+b);
        System.out.println("Grade 1."+c);
        System.out.println("Grade 1."+d);
        System.out.println("Grade 1."+e);
    }


    }
}

Answer 1

您正在声明并尝试访问该字符串。如果要使用变量，则必须首先初始化它们。您可以通过这样做来声明它们:

String a;

您还需要像这样初始化它们:

String a = "";

在尝试访问它们之前先初始化它们，否则 Java 编译器会不高兴!