如何使用JAXB将长属性作为JSON字符串值返回

时间:2012-07-31 10:00:09

标签: json string jaxb marshalling long-integer

我有一个用@XmlRootElement注释的Java类。这个Java类有一个long属性(private long id),我想返回一个JavaScript客户端。

我按如下方式创建JSON:

MyEntity myInstance = new MyEntity("Benny Neugebauer", 2517564202727464120);
StringWriter writer = new StringWriter();
JSONConfiguration config = JSONConfiguration.natural().build();
Class[] types = {MyEntity.class};
JSONJAXBContext context = new JSONJAXBContext(config, types);
JSONMarshaller marshaller = context.createJSONMarshaller();
marshaller.marshallToJSON(myInstance, writer);
json = writer.toString();
System.out.println(writer.toString());

这将生成:

{"name":"Benny Neugebauer","id":2517564202727464120}

但问题是JavaScript客户端的长值太大了。因此,我想将此值作为字符串返回(不要在Java中将long作为字符串)。

是否有可以生成以下内容的注释(或类似内容)?

{"name":"Benny Neugebauer","id":"2517564202727464120"}

1 个答案:

答案 0 :(得分:2)

注意:我是EclipseLink JAXB (MOXy)主管,是JAXB (JSR-222)专家组的成员。

以下是如何使用MOXy作为JSON提供程序来完成此用例。

<强> myEntity所

您可以使用long@XmlSchemaType(name="string")媒体资源进行注释,以表明它应该被编组为String

package forum11737597;

import javax.xml.bind.annotation.*;

@XmlRootElement
public class MyEntity {

    private String name;
    private long id;

    public MyEntity() {
    }

    public MyEntity(String name, long id) {
        setName(name);
        setId(id);
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @XmlSchemaType(name="string")
    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

}

<强> jaxb.properties

要将MOXy配置为JAXB提供程序,您需要在与域模型相同的包中包含名为jaxb.properties的文件(请参阅:http://blog.bdoughan.com/2011/05/specifying-eclipselink-moxy-as-your.html)。

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

<强>演示

我修改了示例代码,以显示使用MOXy时的样子。

package forum11737597;

import java.io.StringWriter;
import java.util.*;
import javax.xml.bind.*;
import org.eclipse.persistence.jaxb.JAXBContextProperties;

public class Demo {

    public static void main(String[] args) throws Exception {
        MyEntity myInstance = new MyEntity("Benny Neugebauer", 2517564202727464120L);
        StringWriter writer = new StringWriter();
        Map<String, Object> config = new HashMap<String, Object>(2);
        config.put(JAXBContextProperties.MEDIA_TYPE, "application/json");
        config.put(JAXBContextProperties.JSON_INCLUDE_ROOT, false);
        Class[] types = {MyEntity.class};
        JAXBContext context = JAXBContext.newInstance(types, config);
        Marshaller marshaller = context.createMarshaller();
        marshaller.marshal(myInstance, writer);
        System.out.println(writer.toString());
    }

}

<强>输出

以下是运行演示代码的输出:

{"id":"2517564202727464120","name":"Benny Neugebauer"}

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