是否可以在父标记和子标记中编写 XMLSchema 实例?

Is it possible to write XMLSchema-instance in parent tag as well as child tag?

我想在 XML 下面创建 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 在 "ServiceAddRQ" 以及 "Service"标签。那么是否可以创建这样的 XML ?

必需 XML :

<ServiceAddRQ echoToken="DummyEchoToken" version="2013/12"
  xmlns="http://www.test.com/schemas/2005/06/messages"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.test.com/schemas/2005/06/messages ServiceAddRQ.xsd">  
        <Service xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="ServiceHotel" availToken="1jMqWGjqrx25Bp60gV2Qggb3">
        </Service>
</ServiceAddRQ>

Java 在 java 生成的代码中生成 XML : 我得到 "Service" 标签的空白 xmlns...

<ServiceAddRQ xmlns="http://www.test.com/schemas/2005/06/messages"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" echoToken="6BB6B47EEEF4290515103925"
    version="2013/12"
    xsi:schemaLocation="http://www.test.com/schemas/2005/06/messages HotelValuedAvailRQ.xsd">   
    <Service xmlns="" xsi:type="ServiceHotel" availToken="1/YncBXZJXY17Z/ygNiO7gcg">        
    </Service>
</ServiceAddRQ>

Java 相同的代码:

    static private Namespace NSSERVICE = Namespace.getNamespace("http://www.test.com/schemas/2005/06/messages");
    static private Namespace NSSCHEMA = Namespace.getNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance");

        String sXMLOut = "";
        Element barceloDS_requests= new Element("ServiceAddRQ",NSSERVICE);  
            barceloDS_requests.setAttribute("echoToken",searchParams.getSessionID().substring(0, 12)+GenTools.getSystemDateWithTime3());
            barceloDS_requests.setAttribute("version","2013/12");
            barceloDS_requests.addNamespaceDeclaration(NSSCHEMA);
            barceloDS_requests.setAttribute("schemaLocation", "http://www.test.com/schemas/2005/06/messages HotelValuedAvailRQ.xsd", NSSCHEMA);

         Namespace xsi = Namespace.getNamespace(GenTools.returnEmptyForNull(sXMLNS_XSI), "http://www.w3.org/2001/XMLSchema-instance");
         Element eleService=new Element("Service");
            eleService.setAttribute("type", "ServiceHotel", xsi);
            eleService.setAttribute("availToken",contractInfo[1]);
    barceloDS_requests.addContent(eleService);
    sXMLOut = new GetXMLOutputter().getXMLOutputter(barceloDS_requests,true);

序列化器添加 xmlns="" 是正确的,因为您创建了一个带有默认命名空间声明的顶级元素,但随后添加了一个不在命名空间中的子元素。要获得您想要的输出,您需要使用与根 ServiceAddRQ 相同的 http://www.test.com/schemas/2005/06/messages 命名空间创建 Service 元素。试试这样:

static private Namespace NSSERVICE = Namespace.getNamespace("http://www.test.com/schemas/2005/06/messages");
static private Namespace NSSCHEMA = Namespace.getNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance");

String sXMLOut = "";
Element barceloDS_requests= new Element("ServiceAddRQ",NSSERVICE);  
barceloDS_requests.setAttribute("echoToken",searchParams.getSessionID().substring(0, 12)+GenTools.getSystemDateWithTime3());
barceloDS_requests.setAttribute("version","2013/12");
barceloDS_requests.addNamespaceDeclaration(NSSCHEMA);
barceloDS_requests.setAttribute("schemaLocation", "http://www.test.com/schemas/2005/06/messages HotelValuedAvailRQ.xsd", NSSCHEMA);

// --------------
// Key change -- Create Service element in the right namespace
Element eleService=new Element("Service",NSSERVICE);
// --------------

eleService.setAttribute("type", "ServiceHotel", NSSCHEMA);
eleService.setAttribute("availToken",contractInfo[1]);
barceloDS_requests.addContent(eleService);

这将创建正确的输出:

<ServiceAddRQ echoToken="DummyEchoToken" version="2013/12"
  xmlns="http://www.test.com/schemas/2005/06/messages"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.test.com/schemas/2005/06/messages ServiceAddRQ.xsd">  
    <Service xsi:type="ServiceHotel" availToken="1jMqWGjqrx25Bp60gV2Qggb3"/>
</ServiceAddRQ>

Service 元素不需要自己的 xmlns:xsi 声明,因为这是从父元素继承的,但是如果您特别想添加一个冗余元素,那么它 可能 可以使用 eleService.addNamespaceDeclaration(NSSCHEMA) 但不能保证,因为当序列化器不改变结果的语义时,它总是可以自由地省略冗余的命名空间声明。