Java 如何修复“解析时到达文件末尾”

我正在编写一个程序来查找和显示具有4个属性（名字、姓氏、年龄、GPA）的班级中GPA最高的学生以及GPA最低的学生

我的代码的输出导致构建成功，但是仍然会出现解析错误，并且没有正确的输出信息

public class app      
{
 public static void main(String args[ ])
 {
 student st1 = new student("Rebecca", "Collins", 22, 3.3);
 student st2 = new student("Alex", "White", 19, 2.8);
 student st3 = new student("Jordan", "Anderson", 22, 3.1);

 student[ ] studentArray = new student[3];

 studentArray[0] = st1;
 studentArray[1] = st2;
 studentArray[2] = st3;

     var maxStudent = studentArray[0];

// Start at 1 because we assumed the first student in the array
// has the current max.
//
for (int i = 1; i < studentArray.length; i++)
 {
    // If the current student has a GPA higher than the student
    // with the current max, make the current student the student
    // with the current max.
    // 
    if(studentArray[i].gpa > maxStudent.getGpa())
    {

     boolean max = false;
     boolean min;
     min = false;
     for (student studentArray1 : studentArray) {
     boolean gpa = false;

     }
 System.out.print("The highest GPA is: "+max);
 System.out.println();

 System.out.print("The lowest GPA is: "+min);
 System.out.println();


  System.out.println("Name: "+ studentArray[i].firstName + " "+ studentArray[i].lastName);

    System.out.println("Age: "+ studentArray[i].age);
     System.out.println("GPA: "+ studentArray[i].gpa);
 }
 }

public class student
 {
     //class variables
     public String firstName;
     public String lastName;
     public int age;
     public double gpa;
     public int max = 0;
     public int min = 0;


     //constructor method
     student(String a, String b, int c, double d)
     {
         firstName = a;
         lastName = b;
         age = c;
         gpa = d;

     }

     student(String a, String b, int c, double d, int e, int f)
     {
         firstName = a;
         lastName = b;
         age = c;
         gpa = d;
         min = e;
         max = f;

     }
     //a method that returns the student's complete name
     String getInfo()
     {
         return getFirstName() +" " + getLastName() +" " + getMax();

     }


     public String getFirstName()
     {
         return firstName;
     }



     public void setFirstName(String fn)
     {
         firstName = fn;
     }

     public String getLastName()
     {
         return lastName;
     }

     public void setLastName(String ln)
     {
         lastName = ln;
     }


     public int getAge()
     {
         return age;
     }


     public void setAge(int x)
     {
         age = x;
     }

     public double getGpa()
     {
         return gpa;
     }


     public void getGpa(double g)
     {
         gpa = g;
     }

     public int getMax()
     {
         return max;

     }
     public void getMax(int e)
     {
         max = e;
     }
     public int getMin()
     {
         return min;
     }
     public void getMin(int f)
     {
         min = f;

     }

 } 

---

我将非常感谢任何能够解决错误的见解和解决方案，以使此代码正常工作。

您发布的代码可能存在许多问题；你似乎在使用一个内部学生班级；大括号不匹配，缩进似乎不一致，在10之前的Java版本中不存在var关键字，我们不知道您安装的JDK或配置的项目编译器级别。你的学生不应该有单独的最小和最大字段

关于一个拥有所有公共领域的班级的优点有一些争论；但当您同时为所有的getter和setter实现时，任何可能的优势都会被否定

你需要两个循环；一个用于查找最小值和最大值，一个用于显示学生。应遵守Java命名约定，类名以大写字母开头。还有一个getGpadouble应该是setter

修复所有这些，它可能看起来像

public class App {
    public static class Student {
        private String firstName;
        private String lastName;
        private int age;
        private double gpa;

        public Student(String a, String b, int c, double d) {
            firstName = a;
            lastName = b;
            age = c;
            gpa = d;
        }

        public String getFirstName() {
            return firstName;
        }

        public void setFirstName(String fn) {
            firstName = fn;
        }

        public String getLastName() {
            return lastName;
        }

        public void setLastName(String ln) {
            lastName = ln;
        }

        public int getAge() {
            return age;
        }

        public void setAge(int x) {
            age = x;
        }

        public double getGpa() {
            return gpa;
        }

        public void setGpa(double g) {
            gpa = g;
        }
    }

    public static void main(String[] args) throws Exception {
        Student st1 = new Student("Rebecca", "Collins", 22, 3.3);
        Student st2 = new Student("Alex", "White", 19, 2.8);
        Student st3 = new Student("Jordan", "Anderson", 22, 3.1);
        Student[] studentArray = { st1, st2, st3 };
        Student maxStudent = studentArray[0];
        Student minStudent = studentArray[0];

        for (int i = 1; i < studentArray.length; i++) {
            if (studentArray[i].getGpa() > maxStudent.getGpa()) {
                maxStudent = studentArray[i];
            }
            if (studentArray[i].getGpa() < minStudent.getGpa()) {
                minStudent = studentArray[i];
            }
        }
        System.out.printf("The highest GPA is: %.1f%n", maxStudent.getGpa());
        System.out.printf("The lowest GPA is: %.1f%n", minStudent.getGpa());
        for (Student s : studentArray) {
            System.out.printf("Name: %s %s%n", s.getFirstName(), s.getLastName());
            System.out.printf("Age: %d%n", s.getAge());
            System.out.printf("GPA: %.1f%n", s.getGpa());
        }
    }
}

而且，如果您使用的是Java8+，您可以通过流式处理学生，映射到gpa值，然后收集统计数据来简化主代码。像

public static void main(String[] args) throws Exception {
    Student st1 = new Student("Rebecca", "Collins", 22, 3.3);
    Student st2 = new Student("Alex", "White", 19, 2.8);
    Student st3 = new Student("Jordan", "Anderson", 22, 3.1);
    Student[] studentArray = { st1, st2, st3 };
    DoubleSummaryStatistics dss = Arrays.stream(studentArray).mapToDouble(Student::getGpa).summaryStatistics();
    System.out.printf("The highest GPA is: %.1f%n", dss.getMax());
    System.out.printf("The lowest GPA is: %.1f%n", dss.getMin());
    Arrays.stream(studentArray).map(s -> String.format("Name: %s %s%nAge: %d%nGPA: %.1f", //
            s.getFirstName(), s.getLastName(), s.getAge(), s.getGpa())).forEach(System.out::println);
}

---

您是否遇到编译器错误？您正在运行什么命令以及确切的错误消息是什么？您发布的代码将无法编译；大括号不匹配，Java中没有关键字var。我没有看到任何文件I/O或代码中任何地方都能产生消息到达文件结尾，而如果你在文件的末尾添加了2个缺失的文件，当它期望更多的源代码时，它不会到达文件的末端，也就是在解析的中间！嗨，欢迎来到StackOverflow！您提供的代码不从文件中读取，因此可能无法引发异常。请检查您是否提供了正确的代码，以及您的问题是否与应用程序的不同部分有关。您所说的var关键字不存在是什么意思？它是在Java10中添加的，并在Java11中扩展到lambdas。@Andreas编辑过。。。Java10之前的版本，等等。

public static void main(String[] args) throws Exception {
    Student st1 = new Student("Rebecca", "Collins", 22, 3.3);
    Student st2 = new Student("Alex", "White", 19, 2.8);
    Student st3 = new Student("Jordan", "Anderson", 22, 3.1);
    Student[] studentArray = { st1, st2, st3 };
    DoubleSummaryStatistics dss = Arrays.stream(studentArray).mapToDouble(Student::getGpa).summaryStatistics();
    System.out.printf("The highest GPA is: %.1f%n", dss.getMax());
    System.out.printf("The lowest GPA is: %.1f%n", dss.getMin());
    Arrays.stream(studentArray).map(s -> String.format("Name: %s %s%nAge: %d%nGPA: %.1f", //
            s.getFirstName(), s.getLastName(), s.getAge(), s.getGpa())).forEach(System.out::println);
}