Java Hello World@OneToMany在带有JPA实体的WebService会话Bean中

女士们，先生们

我正在尝试使用基于SOAP的Web服务设置一个简单的@OneToMany Hello World类型示例。设置相当简单：父/子关系中的两个实体。订单是父母。OrderRows是孩子。所有这些都是使用jdeveloper11g通过向导设置的。除了更改会话bean的名称之外，我没有修改代码

当我试图通过在Orders.java文件中包含@OneToMany注释和相关的列表操作（set、add、remove）来表达这种关系时，就会出现问题。如果我将这些注释掉，并且不返回包含OrderRows的关联列表，则一切正常。包括@OneToMany，不返回任何内容。这可能是某种简单的配置错误，但问题是，当我右键单击会话bean并选择“测试Web服务”，选择getOrdersFindAll（）操作，然后单击“发送请求”时，控制台中不会出现任何错误。我得到的只是一条很好的尖刻的信息，上面写着“没有要展示的内容”。所以我就坐在这里。。。凌晨2点。。。想知道“威士忌探戈狐步舞？”

我浏览了一些网站，比如JavaEE7教程，但都没有用

有人有什么想法吗？或者有人会有一些好的网站来获取一些实用的例子吗

MySessionBean.java

import java.util.List;
import javax.annotation.Resource;
import javax.ejb.SessionContext;
import javax.ejb.Stateless;
import javax.jws.WebService;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

@Stateless(name = "MySession", mappedName = "HelloWs-HelloService-MySession")
@WebService(name = "MySessionBeanService", portName = "MySessionBeanServicePort")
public class MySessionBean {
    @Resource
    SessionContext sessionContext;
    @PersistenceContext(unitName = "HelloService")
    private EntityManager em;

    public MySessionBean() {
    }

    /** <code>select o from Orders o</code> */
    public List<Orders> getOrdersFindAll() {
        return em.createNamedQuery("Orders.findAll").getResultList();
    }
}

My Orders.java实体

import java.io.Serializable;
import java.math.BigDecimal;
import java.util.List;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;

@Entity
@NamedQueries( { @NamedQuery(name = "Orders.findAll", query = "select o from Orders o")     })
public class Orders implements Serializable {
    @Id
    @Column(name = "ORDER_ID", nullable = false)
    private BigDecimal orderId;
    @OneToMany(mappedBy = "orders")
    private List<OrderRows> orderRowsList;

    public Orders() {
    }

    public Orders(BigDecimal orderId, String refName) {
        this.orderId = orderId;
    }

    public BigDecimal getOrderId() {
        return orderId;
    }

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

    public List<OrderRows> getOrderRowsList() {
        return orderRowsList;
    }

    public void setOrderRowsList(List<OrderRows> orderRowsList) {
        this.orderRowsList = orderRowsList;
    }

    public OrderRows addOrderRows(OrderRows orderRows) {
        getOrderRowsList().add(orderRows);
        orderRows.setOrders(this);
        return orderRows;
    }

    public OrderRows removeOrderRows(OrderRows orderRows) {
        getOrderRowsList().remove(orderRows);
        orderRows.setOrders(null);
        return orderRows;
    }
}

---

需要注意的重要事项是XmlAccessorType和XmlTransient注释。这告诉XML转录器不要陷入在两个实体之间来回的无限循环中。据说还有一个@XmlInverseReference注释更好，但我无法让它工作

威士忌探戈狐步+1

<?xml version="1.0" encoding="windows-1252" ?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
         version="2.0">
  <persistence-unit name="HelloService">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>java:/app/jdbc/jdbc/HelloConnDS</jta-data-source>
    <class>helloservice.Orders</class>
    <class>helloservice.OrderRows</class>
    <properties>
      <property name="eclipselink.target-server" value="WebLogic_10"/>
      <property name="javax.persistence.jtaDataSource"     value="java:/app/jdbc/jdbc/HelloConnDS"/>
    </properties>
  </persistence-unit>
</persistence>

@XmlAccessorType(XmlAccessType.FIELD)
public class Child implements Serializable {
...
@XmlTransient
@ManyToOne
@JoinColumn(name = "PARENT_ID")
private Parent parent;