在练习重写equals方法时写测试方法遇到这个问题

先放报错代码：

public class Order {
    int orderId;
    String orderName;

    public int getOrderId() {
        return orderId;
    }

    public void setOrderId(int orderId) {
        this.orderId = orderId;
    }

    public String getOrderName() {
        return orderName;
    }

    public void setOrderName(String orderName) {
        this.orderName = orderName;
    }

 

    public Order(int orderId, String orderName) {
        this.orderId = orderId;
        this.orderName = orderName;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (obj instanceof Order order) {
            return orderId == order.orderId && orderName.equals(order.orderName);
        }
        return false;
    }

    @Test
    public void test2() {
        Order order1 = new Order(1,"2023-3-16购买");
        Order order2 = new Order(1,"2023-3-16购买");
        System.out.println(order1.equals(order2) ? "相同" : "不同");
    }
}

这也是我第一次遇到这个错误“测试类里面只允许存在一个无参构造方法”。
起因：为偷懒、直接在类里面写测试方法。然后实例化类的时候使用了带参的构造方法。
结果：报错!
解决方法：删掉带参的构造方法，实例化时用set()方法给属性赋值。

public class Order {
    int orderId;
    String orderName;

    public int getOrderId() {
        return orderId;
    }

    public void setOrderId(int orderId) {
        this.orderId = orderId;
    }

    public String getOrderName() {
        return orderName;
    }

    public void setOrderName(String orderName) {
        this.orderName = orderName;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (obj instanceof Order order) {
            return orderId == order.orderId && orderName.equals(order.orderName);
        }
        return false;
    }

    @Test
    public void test2() {
        Order order1 = new Order();
        order1.setOrderName("2023-03-13下单");
        order1.setOrderId(1);
        Order order2 = new Order();
        order2.setOrderId(2);
        order2.setOrderName("2023-03-13下单");
        System.out.println(order1.equals(order2) ? "相同订单" : "不同订单");
    }
}

解决！！