diff --git a/W3/com/rental/Car.java b/W3/com/rental/Car.java
new file mode 100644
index 0000000..83620d9
--- /dev/null
+++ b/W3/com/rental/Car.java
@@ -0,0 +1,74 @@
+package com.rental;
+
+public class Car {
+    private final String licensePlate;
+    private String brand;
+    private String model;
+    private double dailyRent;
+    private boolean isRented;
+    private static int totalCars=0;
+    public Car(String licensePlate,String brand,String model,double dailyRent){
+        this.licensePlate=licensePlate;
+        this.brand=brand;
+        this.model=model;
+        if (dailyRent > 0) {
+            this.dailyRent = dailyRent;
+        } else {
+            this.dailyRent = 300;
+            System.out.println("日租金不合法");
+        }
+        this.isRented=false;
+        Car.totalCars+=1;
+    }
+    public String getLicensePlate(){
+        return licensePlate;
+    }
+    public Car(String licensePlate, String brand, String model) {
+        this(licensePlate, brand, model, 300);
+    }
+    public String getBrand(){
+        return brand;
+    }
+    public  String getModel(){
+        return  model;
+    }
+    public double getDailyRent(){
+        return  dailyRent;
+    }
+    public boolean  isRented() {
+        return isRented;
+    }
+    public void setBrand(String brand){
+        this.brand=brand;
+    }
+    public void setmodel(String model){
+        this.model=model;
+    }
+    public void setdailyRent(double dailyRent){
+        if (dailyRent > 0) {
+            this.dailyRent = dailyRent;
+        } else {
+            System.out.println("租金不合法");
+        }
+    }
+    public void rentCar(){
+        if(isRented){
+            System.out.println("车辆已租出，无法再次租用");
+            return;
+        }
+        this.isRented=true;
+    }
+    public void returnCar(){
+        if (!isRented){
+            System.out.println("车辆未被租用，无需归还");
+            return;
+        }
+        this.isRented=false;
+    }
+    public double calculateRent(int days){
+        return dailyRent*days;
+    }
+    public static int getTotalCars(){
+        return totalCars;
+    }
+}
diff --git a/W3/com/rental/TestCar.java b/W3/com/rental/TestCar.java
new file mode 100644
index 0000000..7f495f1
--- /dev/null
+++ b/W3/com/rental/TestCar.java
@@ -0,0 +1,41 @@
+package com.rental;
+public class TestCar {
+    public static void main(String[] args) {
+        // 构造方法
+        Car car1 = new Car("A123", "Toyota", "Camry", 300);
+        Car car2 = new Car("B456", "Honda", "Civic"); // 默认租金
+        Car car3 = new Car("C789", "BMW", "X5", -100); // 非法租金测试
+        // 输出车辆信息
+        System.out.println("所有车辆信息:");
+        displayInfo(car1);
+        displayInfo(car2);
+        displayInfo(car3);
+        // 流程测试
+        System.out.println("租车流程测试:");
+        car1.rentCar();   // 第一次租
+        car1.rentCar();   // 再租
+        car1.returnCar(); // 第一次还
+        car1.returnCar(); // 再还
+        //计算租金
+        System.out.println("租金计算:");
+        double rent = car2.calculateRent(5);
+        System.out.println("car2 租用5天费用: " + rent);
+        // 非法租金
+        System.out.println("非法租金测试:");
+        car2.setdailyRent(-100); // 给一个非法值
+        System.out.println("car2 当前日租金: " + car2.getDailyRent());
+
+        // 输出总车辆数
+        System.out.println("总车辆数");
+        System.out.println("Total Cars: " + Car.getTotalCars());
+    }
+    //输出车辆信息
+    public static void displayInfo(Car car) {
+        System.out.println("车牌号: " + car.getLicensePlate());
+        System.out.println("品牌: " + car.getBrand());
+        System.out.println("型号: " + car.getModel());
+        System.out.println("日租金: " + car.getDailyRent());
+        System.out.println("是否已租出: " + (car.isRented() ? "是" : "否"));
+    }
+}
+
diff --git a/W3/com/rental/测试输出结果.png b/W3/com/rental/测试输出结果.png
new file mode 100644
index 0000000..a899b09
Binary files /dev/null and b/W3/com/rental/测试输出结果.png differ