JAXB @XmlElements擁有的minOccurs = 1

Question

所以我希望有通過類似以下的

@XmlElements(
     { 
      @XmlElement(name = "Apple", type = Apple.class), 
      @XmlElement(name = "Orange", type = Orange.class), 
      @XmlElement(name = "Mango", type = Mango.class) 
     } 
) 
public List<Fruit> getEntries() { 
     return fruitList; 
} 

我想知道@XmlElements被標註是否有強制執行列表中包含至少一個方法列表1元，因爲現在的XSD看起來像

<xs:complexType name="fruitList"> 
    <xs:sequence> 
     <xs:choice minOccurs="0" maxOccurs="unbounded"> 
     <xs:element name="Apple" type="tns:apple"/> 
     <xs:element name="Orange" type="tns:orange"/> 
     <xs:element name="Mango" type="tns:mango"/> 
     </xs:choice> 
    </xs:sequence> 
    </xs:complexType> 

Answer 1

假設蘋果，橘子，芒果，你可能要與@XmlElementRef相當於取代基的XML模式來註釋entries財產水果的子類，而比@XmlElements這對應於選擇的概念。

@XmlElementRef 
public List<Fruit> getEntries() { 
     return fruitList; 
} 

這假定蘋果，橘子，芒果類擴展了水果類，並與@XmlRootElement

@XmlRootElement 
public class Apple extends Fruit { 
    ... 
} 

被註釋更多信息

• http://bdoughan.blogspot.com/2010/11/jaxb-and-inheritance-using-substitution.html
• http://bdoughan.blogspot.com/2010/10/jaxb-and-xsd-choice-xmlelements.html

Answer 2

我建議檢查：

@XmlElements(
    { 
     @XmlElement(name = "Apple", type = Apple.class, required = true), 
     @XmlElement(name = "Orange", type = Orange.class, required = true), 
     @XmlElement(name = "Mango", type = Mango.class, required = true) 
    } 
)