JAX-RS JSON在编组后缺少子对象

Question

我使用Glassfish、EclipseLink和JAX-RS提供REST服务，该服务通过AngularJS/AJAX从网站调用。我返回一个类型为SalesOrder的JSON对象，该对象具有一个类型为List的名为lineItems的属性

我已经成功地调用了REST资源，并返回了一个表示父Salesorder对象的JSON对象，但是，即使服务器端日志表明响应对象具有带有（2）SalesOrderLine对象的Salesorder实体，客户端/浏览器端的JSON对象缺少对子lineItems列表或其内容的任何引用。

Glassfish log contents:
2015-05-03T18:38:30.480-0600|Info: SalesOrder found with UID: 51
2015-05-03T18:38:30.480-0600|Info: Number of line items sent back to the REST service with the order is: 2
2015-05-03T18:38:30.480-0600|Info: Item Quantity is: 10
2015-05-03T18:38:30.480-0600|Info: Item Quantity is: 5
2015-05-03T18:38:30.480-0600|Info: Response status: 200
2015-05-03T18:38:30.480-0600|Info: Response status info: OK
2015-05-03T18:38:30.480-0600|Info: Response class: class org.glassfish.jersey.message.internal.OutboundJaxrsResponse
2015-05-03T18:38:30.480-0600|Info: Response length: -1
2015-05-03T18:38:30.480-0600|Info: Response media type: application/json
2015-05-03T18:38:30.480-0600|Info: Response entity: business.salesOrderMgmt.entity.SalesOrder@2a461205
2015-05-03T18:38:30.480-0600|Info: Response entity number of line items: 2
2015-05-03T18:38:30.481-0600|Info: Response is: OutboundJaxrsResponse{status=200, reason=OK, hasEntity=true, closed=false, buffered=false}

客户端/浏览器端的JSON对象：

{
    "salesOrderUid": 51,
    "orderNumber": "1428002042749",
    "billToCity": "Golden",
    "billToFirstName": "Duke",
    "billToLastName": "Developer",
    "billToState": "CO",
    "billToStreetName": "Technology Row",
    "billToStreetNumber": "12345",
    "billToUnitNumber": null,
    "billToZipCode": 80401,
    "creditCardCsv": 123,
    "creditCardExpirationDate": 1483254001000,
    "creditCardNumber": "123456789012",
    "creditCardType": "Visa",
    "emailAddress": "[e-mail]",
    "nameOnCreditCard": "Duke Developer",
    "salesOrderDate": 1428002043000,
    "salesOrderStatus": "New",
    "shipToCity": "Golden",
    "shipToState": "CO",
    "shipToStreetName": "Technology Row",
    "shipToStreetNumber": "12345",
    "shipToUnitNumber": null,
    "shipToZipCode": 80401,
    "promoCode": "Test",
    "discount": 5,
    "salesTax": 3.2500000000000001804112415015879378188401460647583007812500,
    "shipping": 10,
    "total": 78.2500000000000001804112415015879378188401460647583007812500
}

因此，响应对象的编组似乎正在从子对象中删除。

有没有人看到这一点并想出了解决方法？

Answer 1

感谢您的回复。在我看到这些之前，我最终将以下注释添加到我的实体类中...这有效，所以我没有尝试@XmlId和@XmlIdRef注释。不确定哪一组更好（@Xml... vs@Json...）？

在父（SalesOrder）实体上：@OneToMany（targetEntity=SalesOrderLine.class，cascade=CascadeType.ALL，fetch=FetchType.EAGER，mappedBy=“SalesOrder”）@JsonManagedReference private List lineItems；

在子（SalesOrderLine）实体上：@manytone@PrimaryKeyJoinColumn（name=“SALES\u ORDER\u UID”）@JsonBackReference@JsonIgnore private SalesOrder SalesOrder；

这是可行的，但后来我遇到了一个Glassfish bug“部署一个基本的webapp，3个类，在部署后的第一次尝试中，未能以正确的序列化JSON响应进行响应。”链接：https://java.net/jira/browse/GLASSFISH-21141针对open bug的解决方案建议将Jackson JAR下载到Glassfish模块目录，并删除OSGI缓存。我能够在不删除缓存的情况下使其工作。我的步骤是：1。停止Glassfish 2。下载参考3的（6）个Jackson jars。重新启动Glassfish

Answer 2

从这里的答案可以看出，您已经发现了使用XmlTransient来避免循环依赖。问题是，在编组/解编时，它完全忽略了属性。

那么我们如何解决这个问题呢？鉴于您是如何使用Glassfish的，它默认使用MOXy进行JSON处理，您可以简单地使用@XmlID和@XmlIDREF。下面是我用来测试的

public class SalesOrder {

    private String id;
    private List<SalesOrderLine> salesOrderItems;

    @XmlID
    public String getId() { return id; }
    ...
}

public class SalesOrderLine {
    private String id;
    private String item;
    private SalesOrder salesOrder;

    @XmlIDREF
    public SalesOrder getSalesOrder() { return salesOrder; }
    ...
}

@GET
@Produces(MediaType.APPLICATION_JSON)
public Response getSalesOrder() {
    SalesOrder salesOrder = new SalesOrder("12345");

    List<SalesOrderLine> salesOrderItems = new ArrayList<>();
    SalesOrderLine line = new SalesOrderLine("123", "item1", salesOrder);
    salesOrderItems.add(line);
    line = new SalesOrderLine("124", "item2", salesOrder);
    salesOrderItems.add(line);

    salesOrder.setSalesOrderItems(salesOrderItems);

    return Response.ok(salesOrder).build();
}

而且效果很好。SalesOrder id用作SalesOrder对象中的值。如果没有这些注释，我将从MOXy获得循环依赖性错误。

注意：根据我测试的结果，考虑到使用了JAXB注释支持模块，该解决方案也适用于Jackson。