Customer information management software

This project uses java Basic , After output, the following functions of adding, deleting, modifying and querying can be realized

First

A new project is called myProject, And then in src Create folder inside net.seehope As the home folder , Then create four small folders in turn bean,service,ui,util ;

bean It creates Customer class , service It creates CustomerList class ,

ui It creates CustomerView class ,util It creates CMUtility class

then

Let's write these four classes separately

The first is util In a folder CMUtility Tool class , This is actually a tool kit , When calling this class , You can enter the corresponding type .

package net.seehope.util;

import java.util.Scanner;

public class CMUtility {
// Encapsulating different functions into methods , You can use its functions by calling methods , There is no need to consider the specific function implementation details .

    private static Scanner scanner = new Scanner(System.in);

    // The following method is used to select the interface menu . This method reads the keyboard , If the user types ’1’-’5’ Any character in , Then the method returns . The return value is the character that the user typed .
    public static char readMenuSelection() {
        char c;
        for (; ; ) {
            String str = readKeyBoard(1, false);
            c = str.charAt(0);
            if (c != '1' && c != '2' &&
                    c != '3' && c != '4' && c != '5') {
                System.out.print(" Wrong choice , Please re-enter ：");
            } else break;
        }
        return c;
    }

//     Read a character from the keyboard , And take it as the return value of the method .

    public static char readChar() {
        String str = readKeyBoard(1, false);
        return str.charAt(0);
    }


    // Read a character from the keyboard , And take it as the return value of the method .
    // If the user does not enter a character and returns directly , Method will defaultValue  As return value .

    public static char readChar(char defaultValue) {
        String str = readKeyBoard(1, true);
        return (str.length() == 0) ? defaultValue : str.charAt(0);
    }


    //  Read from the keyboard a length not more than 2 An integer , And take it as the return value of the method .

    public static int readInt() {
        int n;
        for (; ; ) {
            String str = readKeyBoard(2, false);
            try {
                n = Integer.parseInt(str);
                break;
            } catch (NumberFormatException e) {
                System.out.print(" Wrong number input , Please re-enter ：");
            }
        }
        return n;
    }

    // Read from the keyboard a length not more than 2 An integer , And take it as the return value of the method .
    //  If the user does not enter a character and returns directly , Method will defaultValue  As return value .

    public static int readInt(int defaultValue) {
        int n;
        for (; ; ) {
            String str = readKeyBoard(2, true);
            if (str.equals("")) {
                return defaultValue;
            }

            try {
                n = Integer.parseInt(str);
                break;
            } catch (NumberFormatException e) {
                System.out.print(" Wrong number input , Please re-enter ：");
            }
        }
        return n;
    }

    // Read from the keyboard a length not more than limit String , And take it as the return value of the method .
    public static String readString(int limit) {
        return readKeyBoard(limit, false);
    }

    //  Read from the keyboard a length not more than limit String , And take it as the return value of the method .
    //  If the user does not enter a character and returns directly , Method will defaultValue  As return value .

    public static String readString(int limit, String defaultValue) {
        String str = readKeyBoard(limit, true);
        return str.equals("")? defaultValue : str;
    }

    // Input to confirm selection . This method reads... From the keyboard ‘Y’ or ’N’, And take it as the return value of the method .
    public static char readConfirmSelection() {
        char c;
        for (; ; ) {
            String str = readKeyBoard(1, false).toUpperCase();
            c = str.charAt(0);
            if (c == 'Y' || c == 'N') {
                break;
            } else {
                System.out.print(" Wrong choice , Please re-enter ：");
            }
        }
        return c;
    }

        // Read the value in the keyboard 
    private static String readKeyBoard(int limit, boolean blankReturn) {
        String line = "";

        while (scanner.hasNextLine()) {
            line = scanner.nextLine();
            if (line.length() == 0) {
                if (blankReturn) return line;
                else continue;
            }

            if (line.length() < 1 || line.length() > limit) {
                System.out.print(" Input length （ No more than " + limit + "） error , Please re-enter ：");
                continue;
            }
            break;
        }

        return line;
    }

}

next

Write Customer class , Create private variables name gender age phone email, Then Jianli get set Method And constructing nonparametric and parametric methods

package net.seehope.bean;

public class Customer {
    private String name;
    private char gender;
    private int age;
    private String phone;
    private String email;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public char getGender() {
        return gender;
    }

    public void setGender(char gender) {
        this.gender = gender;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Customer() {
    }

    public Customer(String name, char gender, int age, String phone, String email) {
        this.name = name;
        this.gender = gender;
        this.age = age;
        this.phone = phone;
        this.email = email;
    }
}

Until then

CustomerList class , Is used to save the customer object array , And the method of constructing addition, deletion, modification and query is in it .

package net.seehope.service;

import net.seehope.bean.Customer;

public class CustomerList {
    private Customer[] customers;// An array to hold the customer object 
    private int total;// Record the number of saved customer objects 


    /**
     *  Used to initialize customers The constructor of an array 
     * @param totalCustomer： Specify the length of the array 
     */
    public CustomerList(int totalCustomer) {
        customers = new Customer[totalCustomer];
    }

    /**
     *
     * @Description  Add the specified customer to the array 
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:14:51
     * @param customer
     * @return true: Add success   false: Add failure 
     */
    public boolean addCustomer(Customer customer) {
       if(total >=customers.length){
           return false;
       }else{
           customers[total++] = customer;
           return true;
       }
    }
    /**
     *
     * @Description  Modify customer information at the specified index location 
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:17:28
     * @param index
     * @param cust
     * @return true: Modification successful    false： Modification failed 
     */
    public boolean replaceCustomer(int index,Customer cust){
        if(index < 0 || index >=total){
            return false;
        }else{
            customers[index] = cust;
            return true;
        }
    }
    /**
     *  Delete the customer at the specified index location 
     * @Description
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:23:03
     * @param index
     * @return true: Delete successful    false: Delete failed 
     */
    public boolean deleteCustomer(int index){
        if(index < 0 || index >=total){
            return  false;
        }else{
            for(int i =index;i<total - 1;i++){
                customers[i] = customers[i+1];
            }
//            customers[total - 1] = null;
//            total--;
            // or 
            customers[--total] = null;
            return true;
        }
    }
    /**
     *
     * @Description  Get all the customer information 
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:28:53
     * @return
     */
    public Customer[] getAllCustomers(){
        Customer[] custs = new Customer[total];
        for(int i = 0;i < total;i++){
            custs[i] = customers[i];
        }
        return custs;
    }

    /**
     *
     * @Description  Gets the customer at the specified index location 
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:31:45
     * @param index
     * @return  If you find the elements , Then return to ; If not found , Then return to null
     */
    public Customer getCustomer(int index) {
        if(index < 0 || index >= total){
            return null;
        }else{
            return customers[index];
        }
    }

    /**
     *
     * @Description  Get the number of customers stored 
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:32:52
     * @return
     */
    public int getTotal(){
        return total;
//		return customers.length;// FALSE 
    }


}

Last

We wrote CustomerView Class is the first picture shown at the beginning , It's written inside Menu items and items 1-5 Demonstration of methods , Finally, add one more main Method first calls the menu item

package net.seehope.ui;

import net.seehope.bean.Customer;
import net.seehope.service.CustomerList;
import net.seehope.util.CMUtility;

public class CustomerView {
    private CustomerList customerList = new CustomerList(10);

    public CustomerView() {
        Customer customer = new Customer(" Wang Tao ", ' male ', 23, "13212341234", "[email protected]");
        customerList.addCustomer(customer);
    }

    /**
     *  Show 《 Customer information management software 》 Interface method 
     *
     * @Description
     * @author shkstart
     * @date 2021 year 1 month 19 The morning of 11:36:26
     */
    public void enterMainMenu() {

        boolean isFlag = true;
        while (isFlag) {
            System.out.println("\n----------------- Customer information management software -----------------\n");
            System.out.println("                   1  add   Add   customer   Household ");
            System.out.println("                   2  repair   Change   customer   Household ");
            System.out.println("                   3  Delete   except   customer   Household ");
            System.out.println("                   4  customer   Household   Column   surface ");
            System.out.println("                   5  refund         Out \n");
            System.out.print("                    Please select (1-5)：");

            char menu = CMUtility.readMenuSelection();
            switch (menu) {
                case '1':
                    addNewCustomer();
                    break;
                case '2':
                    modifyCustomer();
                    break;
                case '3':
                    deleteCustomer();
                    break;
                case '4':
                    listAllCustomer();
                    break;
                case '5':
                    System.out.print(" Confirm whether to exit (Y/N)");
                    char isExit = CMUtility.readConfirmSelection();
                    if (isExit == 'Y') {
                        isFlag = false;
                    }
                    break;
            }

        }


    }

    private void listAllCustomer() {
        System.out.println("--------------------------- Customer list ---------------------------\n");

        int total = customerList.getTotal();
        if (total == 0) {
            System.out.println(" No customer records ");
        } else {
            System.out.println(" Number \t full name \t Gender \t Age \t\t Telephone \t\t\t\t mailbox ");
            Customer[] custs = customerList.getAllCustomers();
            for (int i = 0; i < custs.length; i++) {
                Customer cust = custs[i];
                System.out.println((i + 1) + "\t" + cust.getName() + "\t" + cust.getGender() + "\t" + cust.getAge() +
                        "\t" + cust.getPhone() + "\t" + cust.getEmail());
            }

            System.out.println("------------------------- Customer list complete -------------------------");

        }
    }

        private void deleteCustomer () {
            System.out.println("--------------------- Delete customer ---------------------");
            int number;
            for(;;){
                System.out.print(" Please select the customer number to be deleted (-1 sign out )：");
                number = CMUtility.readInt();

                if(number == -1){
                    return;
                }

                Customer customer = customerList.getCustomer(number - 1);
                if(customer == null){
                    System.out.println(" Unable to find the specified customer ！");
                }else{
                    break;
                }
            }

            // Found the designated customer 
            System.out.print(" Confirm whether to delete (Y/N)：");
            char isDelete = CMUtility.readConfirmSelection();
            if(isDelete == 'Y'){
                boolean deleteSuccess = customerList.deleteCustomer(number - 1);
                if(deleteSuccess){
                    System.out.println("--------------------- Delete complete ---------------------");
                }else{
                    System.out.println("--------------------- Delete failed ---------------------");
                }
            }else{
                return;
            }
        }

        private void modifyCustomer () {
            System.out.println("--------------------- Modify customer ---------------------");
            Customer cust;
            int number;
            for(;;){
                System.out.print(" Please select the customer number to be modified (-1 sign out )：");
                 number = CMUtility.readInt();
                if(number == -1){
                    return;
                }
                 cust = customerList.getCustomer(number - 1);
                if(cust == null){
                    System.out.println(" Unable to find the specified customer ");
                }else{
                    break;
                }
            }
           // Modify customer information 
            System.out.println(" full name （"+cust.getName()+"):");
            String name =  CMUtility.readString(10,cust.getName());
            System.out.print(" Gender (" + cust.getGender() + "):");
            char gender = CMUtility.readChar(cust.getGender());
            System.out.print(" Age (" + cust.getAge() + "):");
            int age = CMUtility.readInt(cust.getAge());
            System.out.print(" Telephone (" + cust.getPhone() + "):");
            String phone = CMUtility.readString(13, cust.getPhone());
            System.out.print(" mailbox (" + cust.getEmail()+ "):");
            String email = CMUtility.readString(30, cust.getEmail());

            Customer newCust = new Customer(name, gender, age, phone, email);
            boolean isRepalaced = customerList.replaceCustomer(number - 1,newCust);

            if(isRepalaced){
                System.out.println("--------------------- Modified to complete ---------------------");
            }else{
                System.out.println("--------------------- Modification failed ---------------------");
            }
        }

        public void addNewCustomer () {
            System.out.println("--------------------- Add customers ---------------------");
            System.out.print(" full name ：");
            String name = CMUtility.readString(10);
            System.out.print(" Gender ：");
            char gender = CMUtility.readChar();
            System.out.print(" Age ：");
            int age = CMUtility.readInt();
            System.out.print(" Telephone ：");
            String phone = CMUtility.readString(13);
            System.out.print(" mailbox ：");
            String email = CMUtility.readString(30);

            // Encapsulate the above data into objects 
            Customer customer = new Customer(name,gender,age,phone,email);

            boolean isSuccess = customerList.addCustomer(customer);
            if(isSuccess) {
                System.out.println("--------------------- Add to complete ---------------------");
            }else {
                System.out.println("------------------- The customer directory is full , Add failure ---------------");
            }
        }

        public static void main (String[]args){
            CustomerView view = new CustomerView();
            view.enterMainMenu();
        }
    }

Let's take a look at the display effect ：

Add customers ：

  Modify customer ：

there “ Wang Tao ” It is an object established in advance at the beginning of the project , Then when modifying , If enter CMutility The original default value will be kept unchanged .

  Delete customer ：

Customer list ：

 

sign out ：

 

For the time being , It needs to be optimized and adjusted later .