java - 搜索方法不起作用

Question

基本上我有一个 HashMap ，并且搜索方法缺少键盘。下一步应该允许用户输入他们想要搜索的名称。没有错误。输出不允许用户输入他们想要搜索的名称。奇怪的是我可以使用 userInput 方法并且它工作得很好。这是我的代码:店铺声明

//Imports.
import java.util.Scanner;
//********************************************************************  
public class MainApp
{
    //The Scanner is declared here for use throughout the whole MainApp.
    private static Scanner keyboard = new Scanner(System.in);

    public static void main(String[] args)
    {
        new MainApp().start();

    }
    public void start()
    {
//Create a Store named Store and add Employee's to the Store.
        EmployeeStore Store = new EmployeeStore();
        Store.add(new Employee ("James O' Carroll", 18,"hotmail.com"));

        Store.add(new Employee ("Andy Carroll", 1171,"yahoo.com"));

        Store.add(new Employee ("Luis Suarez", 7,"gmail.com"));
//********************************************************************      

/*Test Code.
        Store.searchByName("James O' Carroll");
        Store.print();
        Store.searchByEmail("gmail.com");
        Employee andy = Store.searchByEmail("hotmail.com");
        System.out.println(andy);
        Employee employee = Store.searchByName("James O' Carroll");
        if (employee != null)
        {
            employee.setEmployeeName("Joe");
            employee.setEmployeeId(1);
            employee.setEmployeeEmail("webmail.com");
           Store.edit(employee);
           Store.print();
        }*/
//********************************************************************      

        int choice ;
        System.out.println("Welcome to the Company Database.");
        do
        {
         choice = MenuMethods.getMenuChoice(
                "1.\tView All" +
                "\n2.\tAdd" +
                "\n3.\tDelete" +
                "\n4.\tDelete All " +
                "\n5.\tEdit" +
                "\n6.\tSearch" +
                "\n7.\tPrint"+
                "\n8.\tExit", 8, "Please enter your choice:", "Error [1,8] Only");
         //String temp = keyboard.nextLine();  This prevented entering the choice.
        switch (choice) 
        {
            case 1:
                 System.out.println("View All");
                Store.print();

                break;

        case 2:
             System.out.println("Add");
                Employee employee = MenuMethods.userInput();
                Store.add(employee);

                break;

        case 3:
             System.out.println("Delete");
                //Store.delete();


                break;

        case 4:
                System.out.println("Delete All");
                Store.clear();

                break;
        case 5:
           System.out.println("Edit");
           Employee employee2 = MenuMethods.userInput();
           Store.searchByName(employee2.getEmployeeName());
         if (employee2 != null)
        {
            employee2.setEmployeeName("Joe");
            employee2.setEmployeeId(1);
            employee2.setEmployeeEmail("webmail.com");
           Store.edit(employee2);
           Store.print();
        }

            break;
        case 6:
             System.out.println("Search");
             Employee employee1 = MenuMethods.userInputByName();
             Store.searchByName(employee1.getEmployeeName());


            break;
        case 7:
             System.out.println("Print");
            Store.print();

            break;
        case 8:
             System.out.println("Exit");

            break;
        }


        } while (choice != 8);

     }
}

//Imports
import java.util.Scanner;
//********************************************************************

public class MenuMethods 
{
    private static Scanner keyboard = new Scanner(System.in);



    //Methods for the Company Application menu.
    //Method for validating the choice.
         public static int getMenuChoice(String menuString, int limit, String prompt, String errorMessage) 
         {
                System.out.println(menuString);
                int choice = inputAndValidateInt(1, limit, prompt, errorMessage);
                return choice;
         }
    //********************************************************************
    //This method is used in the getMenuChoice method.
            public static int inputAndValidateInt(int min, int max, String prompt, String errorMessage) 
            {
                int number;
                boolean valid;
                do {
                    System.out.print(prompt);
                    number = keyboard.nextInt();
                    valid = number <= max && number >= min;
                    if (!valid) {
                        System.out.println(errorMessage);
                    }
                } while (!valid);
                return number;
            }
    //********************************************************************
    public static Employee userInput()
    {
         String temp = keyboard.nextLine();
         Employee e = null;
         System.out.println("Please enter the Employee Name:");
         String employeeName = keyboard.nextLine();
         System.out.println("Please enter the Employee ID:");
         int employeeId = keyboard.nextInt();
         temp = keyboard.nextLine();
         System.out.println("Please enter the Employee E-mail address:");
         String employeeEmail  = keyboard.nextLine();
         return e = new Employee(employeeName , employeeId, employeeEmail);

    }
    //********************************************************************
    public static Employee userInputByName()
    {

         Employee e = null;
         System.out.println("Please enter the Employee Name:");
         String employeeName = keyboard.nextLine();
         System.out.println("Please enter the Employee Name:");

         return e =  new Employee(employeeName);

    }
    //********************************************************************



}

mainApp中的搜索方法

case 6:
             System.out.println("Search");
             Employee employee1 = MenuMethods.userInputByName();
             Store.searchByName(employee1.getEmployeeName());


            break;

实际的搜索方法。

public Employee searchByName(String employeeName) 
    {
        Employee employee = map.get(employeeName);    
        System.out.println(employee);
        return employee;
    }
//********************************************************************

userInputByName 方法。这似乎就是问题所在。

 public static Employee userInput()
    {
         String temp = keyboard.nextLine();
         Employee e = null;
         System.out.println("Please enter the Employee Name:");
         String employeeName = keyboard.nextLine();
         System.out.println("Please enter the Employee ID:");
         int employeeId = keyboard.nextInt();
         temp = keyboard.nextLine();
         System.out.println("Please enter the Employee E-mail address:");
         String employeeEmail  = keyboard.nextLine();
         return e = new Employee(employeeName , employeeId, employeeEmail);

    }
    //********************************************************************
    public static Employee userInputByName()
    {

         Employee e = null;
         System.out.println("Please enter the Employee Name:");
         String employeeName = keyboard.nextLine();
         System.out.println("Please enter the Employee Name:");

         return e =  new Employee(employeeName);

    }
    //********************************************************************

Answer 1

让我尽力吧。

首先，为什么你的userInputByName()中有两个println语句？

 public static Employee userInputByName()
    {
         Employee e = null; 
         System.out.println("Please enter the Employee Name:");
         String employeeName = keyboard.nextLine();
         System.out.println("Please enter the Employee Name:"); //!???

         return e =  new Employee(employeeName);
    }

然后，在6的情况下，您只需调用searchByName方法，并不检查搜索是否成功。我建议:

case 6:
    System.out.println("Search");
    Employee employee1 = MenuMethods.userInputByName();
    Employee foundEmployee = Store.searchByName(employee1.getEmployeeName());

    if (foundEmployee != null) {
        System.out.println("Found employee!");
    } else {
        System.out.println("Not Found!");
    }

    break;