Java Jaxb:xsi在根元素中被ns2替换

我使用了以下代码片段

 marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT,
            Boolean.TRUE);
        marshaller.setSchema(getSchema(xsdSchema));
        marshaller.setProperty("com.sun.xml.internal.bind.namespacePrefixMapper",
            new NamespacePrefixMapper() {
                @Override
                public String getPreferredPrefix(String arg0, String arg1,
                    boolean arg2) {
                    return "tf";
                }
            });
        marshaller.setProperty(Marshaller.JAXB_SCHEMA_LOCATION,
            "http://www.xyz.com/tf " + xsdSchema);

        marshaller.marshal(obj, new StreamResult(xml));

输出xml：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<tf:abc xmlns:tf="http://www.xyz.com/tf" xmlns:ns2="http://www.w3.org/2001/XMLSchema-instance" ns2:schemaLocation="http://www.xyz.com/tf schema/myxsd.xsd">

如你所见，我用“ns2”代替“xsi”

我需要的是ns2中的xsi

---

提前感谢。

您可以扩展

名称空间前缀apper

的实现来执行此操作，而不是总是从

getPreferredPrefix
返回
tf
您可以扩展
名称空间前缀apper
的实现来执行此操作，而不是总是从
tf
返回
getPreferredPrefix
您的namespaceprefixmapper应该为声明的每个命名空间返回值：

package mapdemo;

import com.sun.xml.internal.bind.marshaller.NamespacePrefixMapper;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

public class JAXBMarshallerExample {

    public static NamespacePrefixMapper val = new NamespacePrefixMapper() {

        private static final String XSI_URI = "http://www.w3.org/2001/XMLSchema-instance";
        private static final String TF_URI = "http://www.xyz.com/tf/whatever.xsd";

        @Override
        public String getPreferredPrefix(String namespaceUri, String suggestion, boolean requirePrefix) {
            if(XSI_URI.equals(namespaceUri)) {
                return "xsi";
            } else if(TF_URI.equals(namespaceUri)) {
                return "tf";
            }
            return suggestion;
        }

        @Override
        public String[] getPreDeclaredNamespaceUris() {
            return new String[] { XSI_URI, TF_URI};
        }
    };

    public static void main(String[] args) throws Exception {

        JAXBContext context = JAXBContext.newInstance(Output.class);
        Marshaller marshaller = context.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        marshaller.setProperty("com.sun.xml.internal.bind.namespacePrefixMapper", val);

        Output output = new Output();
        output.setId("1");

        marshaller.marshal(output, System.out);
    }

    @XmlRootElement(namespace="http://www.xyz.com/tf/whatever.xsd")
    public static class Output {
        String id;

        public String getId() {
            return id;
        }

        @XmlElement
        public void setId(String id) {
            this.id = id;
        }
    }
}

您的namespaceprefixmapper应该为声明的每个命名空间返回值：

package mapdemo;

import com.sun.xml.internal.bind.marshaller.NamespacePrefixMapper;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

public class JAXBMarshallerExample {

    public static NamespacePrefixMapper val = new NamespacePrefixMapper() {

        private static final String XSI_URI = "http://www.w3.org/2001/XMLSchema-instance";
        private static final String TF_URI = "http://www.xyz.com/tf/whatever.xsd";

        @Override
        public String getPreferredPrefix(String namespaceUri, String suggestion, boolean requirePrefix) {
            if(XSI_URI.equals(namespaceUri)) {
                return "xsi";
            } else if(TF_URI.equals(namespaceUri)) {
                return "tf";
            }
            return suggestion;
        }

        @Override
        public String[] getPreDeclaredNamespaceUris() {
            return new String[] { XSI_URI, TF_URI};
        }
    };

    public static void main(String[] args) throws Exception {

        JAXBContext context = JAXBContext.newInstance(Output.class);
        Marshaller marshaller = context.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        marshaller.setProperty("com.sun.xml.internal.bind.namespacePrefixMapper", val);

        Output output = new Output();
        output.setId("1");

        marshaller.marshal(output, System.out);
    }

    @XmlRootElement(namespace="http://www.xyz.com/tf/whatever.xsd")
    public static class Output {
        String id;

        public String getId() {
            return id;
        }

        @XmlElement
        public void setId(String id) {
            this.id = id;
        }
    }
}

谢谢@SorenD，尝试过你的方法。但它仍然是ns2，而不是xsi.Hi@PavanSky。我已经用完整的代码更新了示例。否则，请更新有关setSchema（…）和您试图封送的对象的信息。谢谢@SorenD，尝试了您的方法。但它仍然是ns2，而不是xsi.Hi@PavanSky。我已经用完整的代码更新了示例。否则，请使用有关setSchema（…）和您试图封送的对象的信息进行更新。