Jax-Rs + Jersey @深度嵌套對象的Post引發內部服務器錯誤

Question

我正在嘗試使用Postman發布json並收到內部服務器錯誤。 我認為問題出在解析json時，因為在發布時，我傳遞的對象也具有嵌套的變量。

訂單類別：

public class Order {

        private long order_id;
        private long user_id;
        private List<OrderDetails> items;
        private Date order_date;
        private Double total;
        private String status;
        ......
}

OrderDetails類：

public class OrderDetails {

    private Product product;
    private Integer quantity;
    ......
}

產品類別：

public class Product {

    private long prodId;
    private String prodName;
    private String prodDesc;
    private float price;
    .......
}

OrderResource類：我想它甚至沒有調用此方法，因為當我將數據作為字符串傳遞並將參數更改為string時，它將進入調用內部並將其顯示在控制台上。 但是，當我再次將其更改為Order時，它拋出的MessageBodyWriter not found for media type=application/json, type=class java.util.HashMap, genericType=class java.util.HashMap.

@POST
    public Response insertorder(Order order, @Context UriInfo uriInfo) throws ApplicationException {
            if (!order.isValid()) {
            throw new ApplicationException("Order is invalid!");
        }

            System.out.println("Order details in Resource: "+order.getUser_id());

        Order response = new OrderDAO().InsertOrder(order);
        String newId = String.valueOf(response.getOrder_id());
        URI url = uriInfo.getAbsolutePathBuilder().path(newId).build();

        return Response.created(url)
                    .status(Status.CREATED)
                    .entity(response)
                    .build();
    }

OrderDAO類：

public Order InsertOrder(Order order) 
{
    Connection connection = null;
    PreparedStatement pstmt = null;
    ResultSet rs = null;
    connection = connect();
    double total=0;
    for(OrderDetails od: order.getItems()) {
        total += od.getProduct().getPrice() * od.getQuantity();
    }

    Order ret = null;

    try {
        pstmt = connection.prepareStatement("INSERT INTO main.orders_table(\n" + 
                "            user_id, order_date, total,status)\n" + 
                "    VALUES (?, ?, ?)",Statement.RETURN_GENERATED_KEYS);    
        pstmt.setLong(1, order.getUser_id());
        pstmt.setDate(2, (Date) order.getOrder_date());
        pstmt.setDouble(3,total);
        pstmt.setString(4,"pending");

        int affectedRows = pstmt.executeUpdate();

        if (affectedRows == 0) {
            throw new SQLException("Creating user failed, no rows affected.");
        }

        try (ResultSet generatedKeys = pstmt.getGeneratedKeys()) {
            if (generatedKeys.next()) {
                System.out.println("Inserted Order Id: "+generatedKeys.getLong(1));
                order.setOrder_id(generatedKeys.getLong(1)); //setting the Order ID to the inserted row Id
            }
            else {
                throw new SQLException("Creating user failed, no ID obtained.");
            }
        }

        ret = new Order(order.getOrder_id(),order.getUser_id(),order.getOrder_date(),order.getTotal(),order.getStatus());
    } 
    catch (Exception e) 
        {
            System.out.println("Error while inserting Order:" + e);
            e.printStackTrace();

        } finally {
            close(connection, pstmt, rs);
        }
    return ret;
}

Json String通過郵遞員傳遞：

{
        "items": [
            {
                "product": {
                    "price": 2,
                    "prodDesc": "Pakistani Orange",
                    "prodId": 1002,
                    "prodName": "ORANGE"
                },
                "quantity": 5
            },
            {
                "product": {
                    "price": 3,
                    "prodDesc": "Kashmir Apple",
                    "prodId": 1001,
                    "prodName": "APPLE"
                },
                "quantity": 5
            }
        ],
        "order_date": "2008-07-06T00:00:00+08:00",
        "user_id": 2
    }

有人可以幫我解決這個問題嗎？ TIA

Answer 1

由於您使用的是諸如Response，Order之類的類，因此您需要提及@consumes和@produces。 嘗試使用Put方法，盡管Post仍然可以在這里工作。

還要正確配置郵遞員，分別提及Content-Type，Accept作為application / json。

@POST
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public Response insertorder(Order order, @Context UriInfo uriInfo) throws ApplicationException {
        if (!order.isValid()) {
        throw new ApplicationException("Order is invalid!");
    }
..
}