在步骤4,我必须使用4个输入的信息项返回一个匿名实例化的Student对象。由于我找不到任何论坛来解决这个问题,我需要一些帮助来设置它或一个例子。
import java.util.Scanner;
public class Students
{
private static Scanner input = new Scanner(System.in);
public static void main(String[] args)
{
Student[] students;
students = getStudents();
printStudents(students);
}
private static Student[] getStudents()
{
Student[] temp;
int how_many;
System.out.print("How many students? ");
how_many = input.nextInt();
purgeInputBuffer();
temp = new Student[input.nextInt()]; // Step 1
for (int i = 0; i < temp.length; i++)
{
getStudent();
temp[i] = getStudent(); // Step 2
}
return temp; // Step 3
}
private static Student getStudent()
{
String name,
address,
major;
double gpa;
System.out.print("Enter name: ");
name = input.nextLine();
System.out.print("Enter address: ");
address = input.nextLine();
System.out.print("Enter major: ");
major = input.nextLine();
System.out.print("Enter GPA: ");
gpa = input.nextDouble();
purgeInputBuffer();
return ___________________________________________________; // Step 4
}
private static void printStudents(Student[] s)
{
System.out.println();
for (int i = 0; i < s.length; i++) // Step 5
{
System.out.println(______); // Step 6
}
}
private static void purgeInputBuffer()
{
// ----------------------------------------------------
// Purge input buffer by reading and ignoring remaining
// characters in input buffer including the newline
// ----------------------------------------------------
input.nextLine();
}
}
答案 0 :(得分:3)
简单地
return new Student(constructor args);
其中constructor args
是Student
构造函数所需的任何参数。
这里使用“匿名”不是标准的Java术语。我想,因为你没有将对象引用分配给局部变量,所以它可以被认为是“匿名的”。只要getStudent()
在<{p}}中调用getStudents()
,它就不会保持匿名状态
temp[i] = getStudent();
所以引用将立即保存(进入数组)。
“匿名”出现在术语“匿名子类”中,但这是一个完全不同的概念,您可能尚未涉及。
答案 1 :(得分:0)
您可以将字段设为私有,并使用参数化构造函数对其进行初始化。
public class Students
{
private static Scanner input = new Scanner(System.in);
private String name;
private String address;
private String major;
double gpa;
public Students(String name, String address, String major, double gpa) {
this.name = name;
this.address = address;
this.gpa = gpa;
this.major = major;
}
public static void main(String[] args)
{
Student[] students;
students = getStudents();
printStudents(students);
}
private static Student[] getStudents()
{
Student[] temp;
int how_many;
System.out.print("How many students? ");
how_many = input.nextInt();
purgeInputBuffer();
temp = new Student[input.nextInt()]; // Step 1
for (int i = 0; i < temp.length; i++)
{
getStudent();
temp[i] = getStudent(); // Step 2
}
return temp; // Step 3
}
private static Student getStudent()
{
String name,
address,
major;
double gpa;
System.out.print("Enter name: ");
name = input.nextLine();
System.out.print("Enter address: ");
address = input.nextLine();
System.out.print("Enter major: ");
major = input.nextLine();
System.out.print("Enter GPA: ");
gpa = input.nextDouble();
purgeInputBuffer();
return new Students(name,address,major,gpa); // Step 4
}
private static void printStudents(Student[] s)
{
System.out.println();
for (int i = 0; i < s.length; i++) // Step 5
{
System.out.println(______); // Step 6
}
}
private static void purgeInputBuffer()
{
// ----------------------------------------------------
// Purge input buffer by reading and ignoring remaining
// characters in input buffer including the newline
// ----------------------------------------------------
input.nextLine();
}
}