疯狂Java讲义第五章课后练习1、2题参考答案

1、编写一个学生类 ，提供 name 、 age 、 gender 、 phone 、 address 、 email 成员变量，且为每个成员 变量提供 set、 get 方法 。 为学生类提供默认的构造器和带所有成员变量的构造器。为学生类提供方法，用于描绘吃、喝、玩、睡等行为 。

package demo05;

public class Student {
    private String name;//姓名
    private int age;//年龄
    private char gender;//性别
    private String tel;//电话
    private String address;//地址
    private String email;//邮箱

    public Student() {

    }

    public Student(String name, int age, char gender, String tel, String address, String email) {
        this.name = name;
        this.age = age;
        this.gender = gender;
        this.tel = tel;
        this.address = address;
        this.email = email;
    }

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

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

    public char getGender() {
        return gender;
    }

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

    public String getTel() {
        return tel;
    }

    public void setTel(String tel) {
        this.tel = tel;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getEmail() {
        return email;
    }

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

    public void eat(){
        System.out.println("吃");
    }

    public void drink() {
        System.out.println("喝水");
    }

    public void play() {
        System.out.println("玩");
    }

    public void sleep() {
        System.out.println("睡觉");
    }

    public String getDetails() {
        return "\t"+name + "\t" + gender + "\t\t" + age + "\t\t\t" + tel + "\t" + address + "\t\t" + email;
    }
    }
}

2、利用第 1 题定义的 Student 类，定义一个 Student[]数组保存多个 Student 对象作为通讯录数据 。程序可通过 name 、 email 、 address 查询，如果找不到数据，则进行友好提示 。

• 下面的code对题目要求的进行了扩充：加入了数组的增删改查。
  1、CMUtility工具类：
  将不同的功能封装为方法，就是可以直接通过调用方法使用它的功能，而无需考虑具体的功能实现细节。（参考某谷培训项目)

import java.util.Scanner;
/**
CMUtility工具类：
将不同的功能封装为方法，就是可以直接通过调用方法使用它的功能，而无需考虑具体的功能实现细节。
*/
public class CMUtility {
    private static Scanner scanner = new Scanner(System.in);
    /**
	用于界面菜单的选择。该方法读取键盘，如果用户键入’1’-’5’中的任意字符，则方法返回。返回值为用户键入字符。
	*/
	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("选择错误，请重新输入：");
            } else break;
        }
        return c;
    }
	/**
	从键盘读取一个字符，并将其作为方法的返回值。
	*/
    public static char readChar() {
        String str = readKeyBoard(1, false);
        return str.charAt(0);
    }
	/**
	从键盘读取一个字符，并将其作为方法的返回值。
	如果用户不输入字符而直接回车，方法将以defaultValue 作为返回值。
	*/
    public static char readChar(char defaultValue) {
        String str = readKeyBoard(1, true);
        return (str.length() == 0) ? defaultValue : str.charAt(0);
    }
    /**
     从键盘读取一个长度不超过2位的整数，并将其作为方法的返回值。
     */
    public static int readInt() {
        int n;
        for (; ; ) {
            String str = readKeyBoard(2, false);
            try {
                n = Integer.parseInt(str);
                break;
            } catch (NumberFormatException e) {
                System.out.print("数字输入错误，请重新输入：");
            }
        }
        return n;
    }
    /**
	从键盘读取一个长度不超过2位的整数，并将其作为方法的返回值。
	如果用户不输入字符而直接回车，方法将以defaultValue 作为返回值。
	*/
    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("数字输入错误，请重新输入：");
            }
        }
        return n;
    }
	/**
	从键盘读取一个长度不超过limit的字符串，并将其作为方法的返回值。
	*/
    public static String readString(int limit) {
        return readKeyBoard(limit, false);
    }
	/**
	从键盘读取一个长度不超过limit的字符串，并将其作为方法的返回值。
	如果用户不输入字符而直接回车，方法将以defaultValue 作为返回值。
	*/
    public static String readString(int limit, String defaultValue) {
        String str = readKeyBoard(limit, true);
        return str.equals("")? defaultValue : str;
    }
	/**
	用于确认选择的输入。该方法从键盘读取‘Y’或’N’，并将其作为方法的返回值。
	*/
    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("选择错误，请重新输入：");
            }
        }
        return c;
    }

    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("输入长度（不大于" + limit + "）错误，请重新输入：");
                continue;
            }
            break;
        }

        return line;
    }
}

2、界面显示类

public class view {
    private list students = new list(10);

    public view() {
        Student cust = new Student("张三", 30,'男',"173444355455","北京天安门",
                "[email protected]");
        students.addStudent(cust);
    }

    public void enterMainMenu() {
        boolean loopFlag = true;
        do {
            System.out.println("\n-----------------学生信息管理软件-----------------\n");
            System.out.println("                   1 添 加 学 生");
            System.out.println("                   2 修 改 学 生");
            System.out.println("                   3 删 除 学 生");
            System.out.println("                   4 学 生 列 表");
            System.out.println("                   5 查 询 学 生");
            System.out.println("                   6 退       出\n");
            System.out.print("                   请选择(1-5)：");

            char key = CMUtility.readMenuSelection();
            System.out.println();
            switch (key) {
                case '1':
                    addNewStudent();
                    break;
                case '2':
                    modifyStudent();
                    break;
                case '3':
                    deleteStudent();
                    break;
                case '4':
                    listAllStudent();
                    break;
                case '5':
                    selectStudent();
                case '6':
                    System.out.print("确认是否退出(Y/N)：");
                    char yn = CMUtility.readConfirmSelection();
                    if (yn == 'Y')
                        loopFlag = false;
                    break;
            }
        } while (loopFlag);
    }

    private void addNewStudent() {
        System.out.println("---------------------添加学生信息---------------------");
        System.out.print("姓名：");
        String name = CMUtility.readString(4);
        System.out.print("性别：");
        char gender = CMUtility.readChar();
        System.out.print("年龄：");
        int age = CMUtility.readInt();
        System.out.print("电话：");
        String phone = CMUtility.readString(15);
        System.out.print("邮箱：");
        String email = CMUtility.readString(15);
        System.out.print("地址：");
        String address = CMUtility.readString(30);

        Student cust = new Student(name, age, gender, phone, address, email);
        boolean flag = students.addStudent(cust);
        if (flag) {
            System.out
                    .println("---------------------添加完成---------------------");
        } else {
            System.out.println("----------------记录已满,无法添加-----------------");
        }
    }

    private void modifyStudent() {
        System.out.println("---------------------修改学生信息---------------------");

        int index = 0;
        Student cust = null;
        for (;;) {
            System.out.print("请选择待修改学生编号(-1退出)：");
            index = CMUtility.readInt();
            if (index == -1) {
                return;
            }

            cust = students.getStudent(index - 1);
            if (cust == null) {
                System.out.println("无法找到指定学生！");
            } else
                break;
        }

        System.out.print("姓名(" + cust.getName() + ")：");
        String name = CMUtility.readString(4, cust.getName());

        System.out.print("性别(" + cust.getGender() + ")：");
        char gender = CMUtility.readChar(cust.getGender());

        System.out.print("年龄(" + cust.getAge() + ")：");
        int age = CMUtility.readInt(cust.getAge());

        System.out.print("电话(" + cust.getTel() + ")：");
        String phone = CMUtility.readString(15, cust.getTel());

        System.out.print("邮箱(" + cust.getEmail() + ")：");
        String email = CMUtility.readString(15, cust.getEmail());

        System.out.print("地址("+ cust.getAddress() + "):");
        String address = CMUtility.readString(30,cust.getAddress());

        cust = new Student(name, age, gender, phone, address, email);

        boolean flag = students.replaceStudent(index - 1, cust);
        if (flag) {
            System.out
                    .println("---------------------修改完成---------------------");
        } else {
            System.out.println("----------无法找到指定学生,修改失败--------------");
        }
    }

    private void deleteStudent() {
        System.out.println("---------------------删除学生---------------------");

        int index = 0;
        Student cust = null;
        for (;;) {
            System.out.print("请选择待删除学生编号(-1退出)：");
            index = CMUtility.readInt();
            if (index == -1) {
                return;
            }

            cust = students.getStudent(index - 1);
            if (cust == null) {
                System.out.println("无法找到指定学生！");
            } else
                break;
        }

        System.out.print("确认是否删除(Y/N)：");
        char yn = CMUtility.readConfirmSelection();
        if (yn == 'N')
            return;

        boolean flag = students.deleteStudent(index - 1);
        if (flag) {
            System.out
                    .println("---------------------删除完成---------------------");
        } else {
            System.out.println("----------无法找到指定学生,删除失败--------------");
        }
    }

    private void listAllStudent() {
        System.out.println("---------------------------学生列表---------------------------");
        Student[] custs = students.getAllStudents();
        if (custs.length == 0) {
            System.out.println("没有学生记录！");
        } else {
            System.out.println("编号\t姓名\t性别\t年龄\t\t电话\t\t\t地址\t\t\t邮箱");
            for (int i = 0; i < custs.length; i++) {
//            System.out.println(i + 1 + "\t" + custs[i].getName() + "\t" + custs[i].getGender() + "\t" + custs[i].getAge() + "\t\t" + custs[i].getPhone() + "\t" + custs[i].getEmail());
                System.out.println((i+1) + "\t" + custs[i].getDetails());
            }
        }

        System.out.println("-------------------------学生列表-------------------------");
    }

    private void selectStudent(){
        String selectNEA = CMUtility.readString(20);
        Student[] custs = students.getAllStudents();//获取数组中的所有对象赋给新的数组
        //遍历数组
        for (int i = 0; i < custs.length; i++) {
            //对数组中的对象中的内容与输入的内容进行比较
            if (selectNEA.equals(custs[i].getName())  ||
                    selectNEA.equals(custs[i].getEmail())  ||
                    selectNEA.equals(custs[i].getAddress()) ){
                System.out.println("存在该学生");
            }else{
                System.out.println("第"+i+"行没有该学生");
            }
        }

    }

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

3、list类业务逻辑（增删改查）

public class list {
    private Student[] students;
    private int total = 0;
    public list(int number){
        students = new Student[number];
    }
    public boolean addStudent(Student student) {
        if (total >= students.length) return false;

        students[total++] = student;
        return true;
    }

    public boolean replaceStudent(int index, Student cust) {
        if (index < 0 || index >= total) return false;

        students[index] = cust;
        return true;
    }

    public boolean deleteStudent(int index) {
        if (index < 0 || index >= total) return false;

        for (int i = index; i <= total - 1; i++) {
            students[i] = students[i + 1];
        }

        students[--total] = null;

        return true;
    }

    public Student[] getAllStudents() {
        Student[] custs = new Student[total];
        for (int i = 0; i < total; i++) {
            custs[i] = students[i];
        }
        return custs;
    }

    public int getTotal() {
        return total;
    }

    public Student getStudent(int index) {
        if (index < 0 || index >= total) return null;

        return students[index];
    }
}

测试