Java 显示信息

在学校的一个项目中，我需要制作一个包含以下选项的菜单系统：

加载员工数据-提示用户输入要加载的员工人数，然后提示输入每个员工的姓名、id（5位数）和年薪

添加新员工-提示用户输入员工数据、姓名、id和年薪

显示所有员工-将每个员工的数据显示到控制台，每行显示一名员工

检索特定员工的数据-提示用户输入员工id并显示相应员工的数据：id、姓名和工资

检索基于范围工资的员工-提示用户输入最低和最高工资，并显示工资在该范围内的所有员工。在单独的行中显示每个员工的所有信息—姓名、id和薪资

出口

每个菜单选项都必须是它自己的，有它自己的方法，他更喜欢我们使用数组而不是列表，这就是为什么我分配了100个空格。这是我到目前为止所拥有的。菜单选项1、2和6在不中断程序的情况下运行。但是任何需要展示东西的地方似乎都被打破了。我的最佳猜测是，在所有方法之间传递和更新数组“employees”存在问题

package practice;

import java.util.Arrays;
import java.util.Scanner;

public class Project {
    
    public static Employee[] loadData() {
        Scanner scanint = new Scanner(System.in);
        Scanner scanstr = new Scanner(System.in);
        
        System.out.println("How many employees would you like to add?"); //Determines how many employees to create
        Employee[] employees = new Employee[100];
        int numberEmployees = scanint.nextInt();
        for (int i = 0; i < numberEmployees; i++) {
            System.out.println("Enter name: ");
            String empName = scanstr.nextLine();
            System.out.println("Enter ID: ");
            int empID = scanint.nextInt();
            System.out.println("Enter Salary: ");
            int empSalary = scanint.nextInt();
            employees[i+1] = new Employee(empName, empID, empSalary); //Add employee to array
        }
        return employees;
    }
    
    public static Employee addEmployee() {
        Scanner scanint = new Scanner(System.in);
        Scanner scanstr = new Scanner(System.in);
        System.out.println("Enter name: ");
        String empName = scanstr.nextLine();
        System.out.println("Enter ID: ");
        int empID = scanint.nextInt();
        System.out.println("Enter salary: ");
        int empSalary = scanint.nextInt();
        return new Employee(empName, empID, empSalary);
    }
    
    public static void displayEmployees(Employee[] employees) {
        for (int i = 0; i < employees.length; i++) {
            if (employees[i] != null) {
                System.out.println(Arrays.toString(employees));
                //System.out.println("Employee Name: " + employees[i].name + " ID: " + employees[i].id + " Salary: " + employees[i].salary);
            }
        }
    }
    
    public static void specificEmployee(Employee[] employees, int id) {
        for (int i = 0; i < employees.length; i++) {
            if (employees[i].id == id) {
                System.out.println("Name: " + employees[i].name + " ID: " + employees[i].id + " Salary: " + employees[i].salary);
            }
            else {
                System.out.println("ID not recognized");
            }
        }
    }
    
    public static void salaryRange(Employee[] employees, int salaryMinimum, int salaryMaximum) {
        for (int i = 0; i < employees.length; i++) {
            if (employees[i].salary >= salaryMinimum && employees[i].salary <= salaryMaximum) {
                System.out.println("Name: " + employees[i].name + " ID: " + employees[i].id + " Salary: " + employees[i].salary);
            }
            else {
                System.out.println("No employees within salary range");
            }
        }
    }

    public static void main(String[] args) {
        
        Scanner scanint = new Scanner(System.in);
        Scanner scanstr = new Scanner(System.in);
        int menuChoice = 0;
        while (menuChoice != 6) {
            System.out.println("\tMenu:");
            System.out.println("1. Load Employee Data");
            System.out.println("2. Add New Employee");
            System.out.println("3. Display All Employees");
            System.out.println("4. Retrieve Specific Employee Data");
            System.out.println("5. Retrieve Employees Within Salary Range");
            System.out.println("6. Exit");
        
            menuChoice = scanint.nextInt();
            Employee[] employees = new Employee[100];
            int amountEmployees;
        
        
            
            if (menuChoice == 1) {
                employees = loadData();
            }
            else if (menuChoice == 2) {
                employees[0] = addEmployee();
            }
            else if (menuChoice == 3) {
                displayEmployees(employees);
            }
            else if (menuChoice == 4) {
                System.out.println("Enter 5 digit employee ID: ");
                int id = scanint.nextInt();
                specificEmployee(employees, id);
            }
            else if (menuChoice == 5) {
                System.out.println("Enter minimum of salary range: ");
                int salaryMinimum = scanint.nextInt();
                System.out.println("Enter maximum of salary range");
                int salaryMaximum = scanint.nextInt();
                salaryRange(employees, salaryMinimum, salaryMaximum);
            }
            else if (menuChoice == 6) {
                break;
            }
            else {
                System.out.println("Invalid Choice");
            }

        }
        scanint.close();
        scanstr.close();

    }

包装实践；
导入java.util.array；
导入java.util.Scanner；
公共类项目{
公共静态员工[]加载数据（）{
Scanner scanint=新扫描仪（System.in）；
Scanner scanstr=新扫描仪（System.in）；
System.out.println（“要添加多少员工？”）；//确定要创建多少员工
员工[]员工=新员工[100]；
int numberEmployees=scanint.nextInt（）；
对于（int i=0；i如果（employees[i].salary>=salarymimum&&employees[i].salary代码中存在一些问题：

while (menuChoice != 6) {
            System.out.println("\tMenu:");
            System.out.println("1. Load Employee Data");
            System.out.println("2. Add New Employee");
            System.out.println("3. Display All Employees");
            System.out.println("4. Retrieve Specific Employee Data");
            System.out.println("5. Retrieve Employees Within Salary Range");
            System.out.println("6. Exit");
        
            menuChoice = scanint.nextInt();
            **Employee[] employees = new Employee[100];**
            int amountEmployees;
        
        
            
            if (menuChoice == 1) {
                employees = loadData();
            }

您已经在while循环中声明了employees数组，因此每次读取输入时，您都在创建一个新的输入。这完全违背了将员工存储在数组中并稍后检索他们的目的，这也使得分配在
menuChoice==1
时变得多余。您必须考虑应该在何处声明数组

public static void specificEmployee(Employee[] employees, int id) {
        for (int i = 0; i < employees.length; i++) {
            if (employees[i].id == id) {
                System.out.println("Name: " + employees[i].name + " ID: " + employees[i].id + " Salary: " + employees[i].salary);
            }
            else {
                System.out.println("ID not recognized");
            }
        }
    }

public static void specific Employee（Employee[]employees，int-id）{
对于（int i=0；i

当你声明一个数组时，默认值为NULL，除非你给它们分配一些值。在这里，你正在迭代整个数组并检查雇员ID。如果数组中某个索引的雇员为NULL，你应该考虑会发生什么。你必须检查这些情况。
您创建的另一个方法中也存在类似的问题。我将让您自己调试它
正如@NomadMaker所建议的，您的第二个菜单项只设置数组的元素0。您不能添加两个或更多员工

我建议您尝试干运行代码，如果您觉得困难，请尝试在ide中调试它。
您可能应该为每个数组包含一个整数，用于定义所使用的元素数。此外，除非您将每个元素设置为null，否则这些元素不能保证为null。您的第二个菜单项仅设置数组的元素0。Y您不能添加两个或更多员工。我建议您花一些时间学习如何使用ide的调试器。