第5章 面向对象(基础篇)

   1、

class Address {
    private String country;
    private String province;
    private String city;
    private String street;
    private String postcode;
    
    Address() {
        
    }
    
    Address(String country, String province, String city, String street, String postcode) {
        this.country = country;
        this.province = province;
        this.city = city;
        this.street = street;
        this.postcode = postcode;
    }
    
    public void show() {
        System.out.println("地址为:"+country+province+city+street+"    邮编: "+postcode);
    }
}
public class AddressTest {

    public static void main(String[] args) {
        new Address("中国", "湖北省", "天门市", "陆羽大道", "427806").show();
    }

}

   2、

class Employee {
    private String id;
    private String name;
    private double base_salary;
    private double increase_salary;
    
    Employee(String id, String name, double base_salary, double increase_salary) {
        this.id = id;
        this.name = name;
        this.base_salary = base_salary;
        this.increase_salary = increase_salary;
    }
    
    public double getIncrease_salary() {
        return increase_salary;
    }
    
    public double getTotalSalary() {
        return increase_salary + base_salary;
    }
    
}
public class EmployeeDemo {

    public static void main(String[] args) {
        Employee li = new Employee("211016040", "李阿昀", 5000, 2500.50);
        System.out.println("薪水增长额:"+li.getIncrease_salary());
        System.out.println("增长后的工资总额为:"+li.getTotalSalary());
    }

}

   3、

public class practice3 {

    public static void main(String[] args) {
        String str = "want you to know one thing";
        System.out.println("字母n出现的次数:"+getCharacterCounts(str, 'n'));
        System.out.println("字母o出现的次数:"+getCharacterCounts(str, 'o'));
    }
    
    public static int getCharacterCounts(String str, char ch) {
        int count = 0;
        
        for(int index = 0; (index = str.indexOf(ch, index)) != -1; index++) {
            count++;
        }
        return count;
    }

}

   4、

class Dog {
    private String name;
    private String color;
    private int age;
    public Dog(String name, String color, int age) {
        this.name = name;
        this.color = color;
        this.age = age;
    }
    
    public void show() {
        System.out.println("狗狗的名字是"+name+",颜色是"+color+",年龄是"+age+"岁。");
    }    
}
public class DogTest {

    public static void main(String[] args) {
        new Dog("旺财", "黄色", 5).show();
    }

}

   5、

class User {
    private String name;
    private String psw;
    private static int count = 0;
    
    User() {
        count++;
        System.out.println("创建第"+count+"个对象。");
    }
    User(String name) {
        this.name = name;
        count++;
        System.out.println("创建第"+count+"个对象。");
    }
    User(String name, String psw) {
        this.name = name;
        this.psw = psw;
        count++;
        System.out.println("创建第"+count+"个对象。");
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPsw() {
        return psw;
    }
    public void setPsw(String psw) {
        this.psw = psw;
    }
    
    public void show() {
        System.out.println("用户名:"+name+",口令:"+psw);
    }
}
public class UserTest {

    public static void main(String[] args) {
        new User().show();
        new User("叶子").show();
        new User("李阿昀", "liayun").show();
    }

}

   6、

public class StringTest {

    public static void main(String[] args) {
        getTime("Java 技术学习班 20070326");
        replace("MLDN JAVA", "JAVA", "J2EE");
        getChar("Java 技术学习班 20070326", 8);
        clear_0("Java 技术学习班 20070326", '0');
        clear_space("Java 技术学习班 20070326");
        getBirthday("429006199210061852");
    }
    //(1)
    public static void getTime(String str) {
        int index = str.indexOf('2');
        int year = Integer.parseInt(str.substring(index, index + 4));
        int month = Integer.parseInt(str.substring(index + 4, index + 6));
        int day = Integer.parseInt(str.substring(index + 6));
        System.out.println("开班日期:"+year+"年"+month+"月"+day+"日");
    }
    //(2)
    public static void replace(String str, String oldStr, String newStr) {
        System.out.println("替换之后的字符串为:"+str.replaceAll(oldStr, newStr));
    }
    //(3)
    public static void getChar(String str, int index) {
        System.out.println("""+str+"""+"中第"+index+"个字符为:"+str.charAt(index));
    }
    //(4)
    public static void clear_0(String str, char ch) {
        str = str.replaceAll("0", "");
        System.out.println("""+str+"""+"清除所有的0后为:"+str);
    }
    //(5)
    public static void clear_space(String str) {
        String[] s = str.split(" ");
        System.out.print("""+str+"""+"清除所有的空格后为:");
        for(int x = 0; x < s.length; x++) {
            System.out.print(s[x]);
        }
        System.out.println();
    }
    //(6)
    public static void getBirthday(String birthday) {
        int year = Integer.parseInt(birthday.substring(6, 10));
        int month = Integer.parseInt(birthday.substring(10, 12));
        int day = Integer.parseInt(birthday.substring(12, 14));
        
        System.out.println("身份证号为("+birthday+")人的生日为:"+year+"年"+month+"月"+day+"日");
    }

}

   7、

package chapter5;
class Staff {
    private String id;
    private String name;
    private double salary;
    private String department;
    
    public Staff(String id) {
        this.id = id;
        name = "无名氏";
        salary = 0;
        department = "未定";
    }

    public Staff(String id, String name) {
        this.id = id;
        this.name = name;
        salary = 1000;
        department = "后勤";
    }

    public Staff(String id, String name, double salary, String department) {
        this.id = id;
        this.name = name;
        this.salary = salary;
        this.department = department;
    }
    
    public Staff() {
        
    }
        
    public void show() {
        System.out.println("员工信息为--->工号:"+id+",姓名:"+name+",薪水:"+salary
                +",部门:"+department);
    }    
}
public class StaffTest {

    public static void main(String[] args) {
        new Staff().show();
        new Staff("001").show();
        new Staff("002", "李阿昀").show();
        new Staff("003", "李子", 25000.5, "研发部").show();
    }
}

   8、

package chapter5;

public class Account {
    private String accontName;
    private double balance;
    
    public Account(String accontName, double balance) {
        this.accontName = accontName;
        this.balance = balance;
    }
    
    public double getBalance() {
        return balance;
    }
    
}

   9、

class Book {
    private String title;
    private String id;
    private double price;
    private static int count = 0;//静态数据成员册数
    
    Book(String title, double price) {
        this.title = title;
        this.id = "00"+(++count);
        this.price = price;
    }

    public String getTitle() {
        return title;
    }


    public void setTitle(String title) {
        this.title = title;
    }


    public String getId() {
        return id;
    }


    public void setId(String id) {
        this.id = id;
    }


    public double getPrice() {
        return price;
    }


    public void setPrice(double price) {
        this.price = price;
    }
    
    public static int getCount() {
        return count;
    }
    
    
}
public class BookTest {

    public static void main(String[] args) {
        Book[] books = {new Book("小王子", 34.5),
                        new Book("西游记", 56.5),
                        new Book("Thinking In Java", 34.5)};
        
        for(int x = 0; x < books.length; x++) {
            System.out.println("编号:"+books[x].getId()+",书名:"+books[x].getTitle()+
                                "价格:"+books[x].getPrice());
        }
        System.out.println("图书的总册数为:"+Book.getCount()+"册");
    }

}
原文地址:https://www.cnblogs.com/yerenyuan/p/5236692.html