使用jaxb进行解组时各个XML元素的行号 [英] Line number of individual XML element while unmarshalling using jaxb

问题描述

我有一个具有属性名称和地址的Person。我用XML显示它。从XML解组时，可以分别获取名称和地址的行号。
我尝试使用Locator。但它没有提供单独的行号。

解决方案

EclipseLink JAXB（MOXy） 和JAXB参考实现都有自己的 @XmlLocation 支持此用例的注释。这允许您将对应于该对象的XML元素上的位置存储为 org.xml.sax.Locator 的实例。由于我是MOXy领导者，我将演示使用MOXy：

人

< pre class =lang-java prettyprint-override> import javax.xml.bind.annotation。*;
import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
import org.eclipse.persistence.oxm.annotations.XmlLocation;
import org.xml.sax.Locator;

@XmlRootElement
@XmlAccessorType（XmlAccessType.FIELD）
public class Person {

@XmlJavaTypeAdapter（value = StringAdapter.class）
字符串名称;

地址;

@XmlLocation
定位器定位器;

}


地址

  import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter; 
 import org.eclipse.persistence.oxm.annotations.XmlLocation; 
 import org.xml.sax.Locator; 
 
公共类地址{
 
 @XmlJavaTypeAdapter（value = StringAdapter.class）
 private String street; 
 
 @XmlLocation 
定位器定位器; 
 
} 
  

StringAdapter

  import javax.xml.bind.annotation。*; 
 import javax.xml.bind.annotation.adapters.XmlAdapter; 
 import org.eclipse.persistence.oxm.annotations.XmlLocation; 
 import org.xml.sax.Locator; 
 
 public class StringAdapter extends XmlAdapter< StringAdapter.AdaptedString，String> {
 
 public static class AdaptedString {
 
 @XmlValue 
 public String value; 
 
 @XmlLocation 
 @XmlTransient 
定位器定位器; 
 
} 
 
 @Override 
 public String unmarshal（AdaptedString v）抛出异常{
 System.out.println（v.value ++ v.locator.getLineNumber（））; 
返回v.value; 
} 
 
 @Override 
 public AdaptedString marshal（String v）throws Exception {
 AdaptedString adaptedString = new AdaptedString（）; 
 adaptString.value = v; 
返回adaptationString; 
} 
 
} 
  

jaxb.properties

要将MOXy指定为JAXB提供程序，您需要在其中包含一个名为 jaxb.properties 的文件与您的域模型相同的包，包含以下条目。

  javax.xml.bind.context.factory = org.eclipse.persistence .jaxb.JAXBContextFactory 
  

演示

  import java.io.File; 
 import javax.xml.bind。*; 
 
公共类演示{
 
 public static void main（String [] args）throws Exception {
 JAXBContext jc = JAXBContext.newInstance（Person.class）; 
 
 Unmarshaller unmarshaller = jc.createUnmarshaller（）; 
文件xml =新文件（src / forum14455596 / input.xml）; 
人格=（人）unmarshaller.unmarshal（xml）; 
 
 System.out.println（Person：+ person.locator.getLineNumber（））; 
 System.out.println（Address：+ person.address.locator.getLineNumber（））; 
} 
 
} 
  

输出

  Jane Doe 3 
 1 A Street 5 
人：2 
地址：4 
  

I have a class Person with attributes name and address. I display it in a XML. While unmarshalling from XML will it be possible to get line number for name and address separately. I tried using Locator. But it does not provide individual line numbers.

解决方案

The EclipseLink JAXB (MOXy) and the JAXB reference implementation each have their own @XmlLocation annotations for supporting this use case. This allows you to store the location on the XML element corresponding to the object as an instance of org.xml.sax.Locator. Since I'm the MOXy lead, I will demonstrate using MOXy:

Person

import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
import org.eclipse.persistence.oxm.annotations.XmlLocation;
import org.xml.sax.Locator;

@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Person {

    @XmlJavaTypeAdapter(value=StringAdapter.class)
    String name;

    Address address;

    @XmlLocation
    Locator locator;

}

Address

import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
import org.eclipse.persistence.oxm.annotations.XmlLocation;
import org.xml.sax.Locator;

public class Address {

    @XmlJavaTypeAdapter(value=StringAdapter.class)
    private String street;

    @XmlLocation
    Locator locator;

}

StringAdapter

import javax.xml.bind.annotation.*;
import javax.xml.bind.annotation.adapters.XmlAdapter;
import org.eclipse.persistence.oxm.annotations.XmlLocation;
import org.xml.sax.Locator;

public class StringAdapter extends XmlAdapter<StringAdapter.AdaptedString, String> {

    public static class AdaptedString {

        @XmlValue
        public String value;

        @XmlLocation
        @XmlTransient
        Locator locator;

    }

    @Override
    public String unmarshal(AdaptedString v) throws Exception {
        System.out.println(v.value + " " + v.locator.getLineNumber());
        return v.value;
    }

    @Override
    public AdaptedString marshal(String v) throws Exception {
        AdaptedString adaptedString = new AdaptedString();
        adaptedString.value = v;
        return adaptedString;
    }

}

jaxb.properties

To specify MOXy as your JAXB provider you need to include a file called jaxb.properties in the same package as your domain model with the following entry.

javax.xml.bind.context.factory=org.eclipse.persistence.jaxb.JAXBContextFactory

Demo

import java.io.File;
import javax.xml.bind.*;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(Person.class);

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        File xml = new File("src/forum14455596/input.xml");
        Person person = (Person) unmarshaller.unmarshal(xml);

        System.out.println("Person:  " + person.locator.getLineNumber());
        System.out.println("Address:  " + person.address.locator.getLineNumber());
    }

}

Output

Jane Doe 3
1 A Street 5
Person:  2
Address:  4

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