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今天学习了继承、多态

ScreenShot_2026-10-02_171817_364.png

创建厂家实例用明确的子类 创建用户实例用父类

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public class Day37SmartHomeQuotationTest {
    public static void main(String[] args) {
        //  厂家
        Day37Company vendor = new Day37Company("张经理","13829871635","视声智能","广州市黄埔区","KNX全屋智能/灯光/安防");
        //  业主
        Day37Person client1 = new Day37Customer("马思纯","15138473848","上海市静安区",533);
        //  商家
        Day37Person client2 = new Day37Company("李经理","13150432864","杜亚窗帘","杭州市拱墅区","智能窗帘/智能门锁");
        //  报价单：厂家给业主
        Day37SmartHomeQuotation quote1 = new Day37SmartHomeQuotation(
                "Q-SM-20260001-000001",
                "2026-10-02 16:35:11",
                "马女士静安府全屋智能",
                client1,
                vendor,
                35800.0, 5800.0, 6500.0, 4200.0, 2000.0
        );
        //  报价单：厂家给商家
        Day37SmartHomeQuotation quote2 = new Day37SmartHomeQuotation(
                "Q-SM-20260001-000002",
                "2026-10-02 16:37:20",
                "杜亚展厅智能改造",
                client2,
                vendor,
                28000.0, 3500.0, 4000.0, 2500.0, 1500.0
        );
        //  打印报价单
        System.out.println(quote1);
        System.out.println();
        System.out.println(quote2);
        // 打印完整客户信息
        System.out.println();
        System.out.println("======= 完整客户信息（点击查看）=======");
        System.out.println(quote1.getClientFullInfo());
        System.out.println(quote2.getClientFullInfo());
    }
}

instanceof 是运行时类型判断 父类引用 Person 装子类对象后，只能调用父类定义的方法 想调子类特有方法 → instanceof 判断 → (子类) 引用 强转 → 调用 LocalDATeTime日期输出 DateTimeFormatter格式化输出 类字段引用了子类 文本块输出 String.format()格式化输出 StringBuilder动态长度格式化输出 toString()重写

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import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class Day37SmartHomeQuotation {
    private String quotationNo = "";
    private String quotationDate = "";
    private String projectName = "";
    private Day37Person client;
    private Day37Company vendor;
    private double deviceCost = 0.0;
    private double materialCost = 0.0;
    private double installCost = 0.0;
    private double debugCost = 0.0;
    private double otherCost = 0.0;
    private static final String QUOTATION_TITLE = "智能家居报价单";
    private static final String QUOTATION_TITLE_LINE = "----------";
    private static final String QUOTATION_PROJECT_TEXT = """
            报价编号：%s
            报价日期：%s
            报价单位：%s
            项目名称：%s
            用户信息：%s
            """;
    private static final DateTimeFormatter DATE_TIME_INPUT_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
    private static final DateTimeFormatter DATE_TIME_OUTPUT_FORMAT = DateTimeFormatter.ofPattern("yyyy年MM月dd日 HH:mm:ss");

    public Day37SmartHomeQuotation() {
    }

    public Day37SmartHomeQuotation(String quotationNo, String quotationDate, String projectName, Day37Person client, Day37Company vendor, double deviceCost, double materialCost, double installCost, double debugCost, double otherCost) {
        this.setQuotationNo(quotationNo);
        this.setQuotationDate(quotationDate);
        this.setProjectName(projectName);
        this.setClient(client);
        this.setVendor(vendor);
        this.setDeviceCost(deviceCost);
        this.setMaterialCost(materialCost);
        this.setInstallCost(installCost);
        this.setDebugCost(debugCost);
        this.setOtherCost(otherCost);
    }

    public void setQuotationNo(String quotationNo) {
        this.quotationNo = quotationNo;
    }

    public void setQuotationDate(String quotationDate) {
        this.quotationDate = quotationDate;
    }

    public void setProjectName(String projectName) {
        this.projectName = projectName;
    }

    public void setClient(Day37Person client) {
        this.client = client;
    }

    public void setVendor(Day37Company vendor) {
        this.vendor = vendor;
    }

    public void setDeviceCost(double deviceCost) {
        this.deviceCost = deviceCost;
    }

    public void setMaterialCost(double materialCost) {
        this.materialCost = materialCost;
    }

    public void setInstallCost(double installCost) {
        this.installCost = installCost;
    }

    public void setDebugCost(double debugCost) {
        this.debugCost = debugCost;
    }

    public void setOtherCost(double otherCost) {
        this.otherCost = otherCost;
    }

    public String getQuotationNo() {
        return this.quotationNo;
    }

    public String getQuotationDate() {
        LocalDateTime dateTime = LocalDateTime.parse(this.quotationDate, DATE_TIME_INPUT_FORMAT);
        return dateTime.format(DATE_TIME_OUTPUT_FORMAT);
    }

    public String getProjectName() {
        return this.projectName;
    }

    public Day37Person getClient() {
        return this.client;
    }

    public Day37Company getVendor() {
        return this.vendor;
    }

    public double getDeviceCost() {
        return this.deviceCost;
    }

    public double getMaterialCost() {
        return this.materialCost;
    }

    public double getInstallCost() {
        return this.installCost;
    }

    public double getDebugCost() {
        return this.debugCost;
    }

    public double getOtherCost() {
        return this.otherCost;
    }

    public String getClientDisplay() {
        if (client instanceof Day37Customer) {
            Day37Customer cu = (Day37Customer) client;
            return "（业主）" + cu.getName();
        } else if (client instanceof Day37Company) {
            Day37Company co = (Day37Company) client;
            return "（公司）" + co.getCompanyName();
        }
        return "";
    }

    public String getClientFullInfo() {
        if (client instanceof Day37Customer) {
            Day37Customer cu = (Day37Customer) client;
            return "（业主）" + "电话：" + cu.getPhone() + "，地址：" + cu.getHouseAddress() + "，房屋面积：" + cu.getHouseArea() + "m²";
        } else if (client instanceof Day37Company) {
            Day37Company co = (Day37Company) client;
            return "（公司）" + "联系人：" + co.getName() + "，电话：" + co.getPhone() + "，地址：" + co.getAddress();
        }
        return "";
    }

    @Override
    public String toString() {
        double totalAmount = deviceCost + materialCost + installCost + debugCost + otherCost;
        StringBuilder sb = new StringBuilder();

        //  静态拼接报价单的头
        sb.append(QUOTATION_TITLE_LINE.repeat(4)).append(QUOTATION_TITLE).append(QUOTATION_TITLE_LINE.repeat(4)).append("\n");
        sb.append(String.format(QUOTATION_PROJECT_TEXT, quotationNo, getQuotationDate(), vendor.getCompanyName(), projectName, getClientDisplay()));
        sb.append(QUOTATION_TITLE_LINE.repeat(9)).append("\n");

        //  动态拼接报价单金额（按照总金额格式化后的长度右对齐）
        String totalStr = String.format("%,.2f", totalAmount);
        int width = totalStr.length();

        sb.append(String.format("项目金额：%," + width + ".2f" + " 元%n", totalAmount));
        sb.append("其中：\n");
        sb.append(String.format("设备金额：%," + width + ".2f" + " 元%n", deviceCost));
        sb.append(String.format("材料金额：%," + width + ".2f" + " 元%n", materialCost));
        sb.append(String.format("安装金额：%," + width + ".2f" + " 元%n", installCost));
        sb.append(String.format("调试金额：%," + width + ".2f" + " 元%n", debugCost));
        sb.append(String.format("其他金额：%," + width + ".2f" + " 元%n", otherCost));
        sb.append(QUOTATION_TITLE_LINE.repeat(9)).append("\n");

        return sb.toString();
    }
}

父类 手机号正则 构造方法调用setter方法 toString()重写

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public class Day37Person {
    private static final String  PHONE_REGEX = "^1[3-9]\\d{9}$";
    private static final String ERROR_PHONE_FORMAT = "手机号码格式不正确，已置空！";

    private String name = "";
    private String phone = "";

    public Day37Person() {
    }

    public Day37Person(String name, String phone) {
        setName(name);
        setPhone(phone);
    }

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

    public void setPhone(String phone) {
        if (phone != null && phone.matches(PHONE_REGEX) ){
            this.phone = phone;
        }else{
            System.out.println(ERROR_PHONE_FORMAT);
            this.phone = "";
        }
    }

    public String getName() {
        return this.name;
    }

    public String getPhone() {
        return this.phone;
    }

    @Override
    public String toString() {
        return "姓名：" + this.getName() + "，电话：" + this.getPhone();
    }

    public String introduce(){
        return "";
    }
}

Company子类，继承Person类 构造方法调用父类构造方法 构造方法调用setter方法 toString()重写 StringBuilder()拼接

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public class Day37Company extends Day37Person {
    private String companyName = "";
    private String address = "";
    private String serviceScope = "";

    public Day37Company() {
    }

    public Day37Company(String name, String phone, String companyName, String address, String serviceScope) {
        super(name, phone);
        setCompanyName(companyName);
        setAddress(address);
        setServiceScope(serviceScope);
    }

    public void setCompanyName(String companyName) {
        this.companyName = companyName;
    }

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

    public void setServiceScope(String serviceScope) {
        this.serviceScope = serviceScope;
    }

    public String getCompanyName() {
        return this.companyName;
    }

    public String getAddress() {
        return this.address;
    }

    public String getServiceScope() {
        return this.serviceScope;
    }

    @Override
    public String toString() {
        return "【公司】联系人：" + this.getName() + "，电话：" + this.getPhone() + "，品牌：" + this.getCompanyName() + "，地址：" + this.getAddress() + "，服务范围：" + this.getServiceScope();
    }

    public String introduce() {
        StringBuilder sb = new StringBuilder();
        sb.append("您好，我们是").append(this.getCompanyName()).append("，公司位于").append(this.getAddress()).append("，主营").append(this.getServiceScope()).append("，联系人").append(this.getName());
        return sb.toString();
    }
}

Worker子类，继承Person类 构造方法调用父类构造方法 构造方法调用setter方法 setter方法判断边界 StringBuilder()拼接 toString()重写

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public class Day37Worker extends Day37Person {
    private static final String ERROR_WORK_YEAR = "工龄0-70，其他无效！已置0";
    private static final String ERROR_SCORE = "评分只能0-5，整数或一位小数！已置0";

    private String jobType = "";
    private int workYear = 0;
    private double score = 0.0;

    public Day37Worker() {
    }

    public Day37Worker(String name, String phone, String jobType, int workYear, double score) {
        super(name, phone);
        setJobType(jobType);
        setWorkYear(workYear);
        setScore(score);
    }

    public void setJobType(String jobType) {
        this.jobType = jobType;
    }

    public void setWorkYear(int workYear) {
        if (workYear >= 0 && workYear <= 70) {
            this.workYear = workYear;

        } else {
            System.out.println(ERROR_WORK_YEAR);
            this.workYear = 0;
        }
    }

    public void setScore(double score) {
        if (score >= 0 && score <= 5) {
            this.score = score;

        } else {
            System.out.println(ERROR_SCORE);
            this.score = 0.0;
        }
    }

    public String getJobType() {
        return this.jobType;
    }

    public int getWorkYear() {
        return this.workYear;
    }

    public double getScore() {
        return this.score;
    }

    @Override
    public String toString() {
        return "【师傅】：" + this.getName() + "，" + this.getPhone() + "，" + this.getJobType() + "，" + this.getWorkYear() + "，" + this.getScore();
    }

    public String introduce() {
        StringBuilder sb = new StringBuilder();
        sb.append("我是").append(this.getJobType()).append(",从业").append(this.getWorkYear()).append("年，评分").append(this.getScore()).append("，电话").append(this.getPhone());
        return sb.toString();
    }
}

Customer子类，继承Person类 构造方法调用父类构造方法 构造方法调用setter方法 toString()重写 StringBuilder()拼接

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public class Day37Customer extends Day37Person {
    private static final String ERROR_HOUSE_AREA = "面积大于0小于5000，整数或一位小数！";

    private String houseAddress = "";
    private double houseArea = 0.0;

    public Day37Customer() {
    }

    public Day37Customer(String name, String phone, String houseAddress, double houseArea) {
        super(name, phone);
        setHouseAddress(houseAddress);
        setHouseArea(houseArea);
    }

    public void setHouseAddress(String houseAddress) {
        this.houseAddress = houseAddress;
    }

    public void setHouseArea(double houseArea) {
        if (houseArea > 0.0 && houseArea < 5000.0) {
            this.houseArea = houseArea;

        } else {
            System.out.println(ERROR_HOUSE_AREA);
            this.houseArea = 0.0;
        }
    }

    public String getHouseAddress() {
        return this.houseAddress;
    }

    public double getHouseArea() {
        return this.houseArea;
    }

    @Override
    public String toString() {
        return "【业主】：" + this.getName() + "，" + this.getPhone() + "，" + this.getHouseAddress() + "，" + this.getHouseArea() + "m²";
    }

    public String introduce() {
        StringBuilder sb = new StringBuilder();
        sb.append("业主").append(this.getName()).append(",房屋面积").append(this.getHouseArea()).append("m²，位于").append(this.getHouseAddress()).append("，需要智能家居报价。");
        return sb.toString();
    }
}
Java
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