嗨，我正在尝试记录hp alm中的缺陷。我写了一个java程序。它给我错误500.因为我试图把相同的ID

Question

我获取了缺陷网址：

   String defectUrl = conn.buildEntityCollectionUrl("defect");
    defectUrl += "/98";

    Map<String, String> requestHeaders = new HashMap<String, String>();
    requestHeaders.put("Accept", "application/xml");

    Response res = conn.httpGet(defectUrl, null, requestHeaders);

然后转换为实体：

    String postedEntityReturnedXml = res.toString();
    Entity entity = EntityMarshallingUtils.marshal(Entity.class,postedEntityReturnedXml);

而不是更改字段值：

    List<Field> fields = entity.getFields().getField();

    for (Field f : fields) {
        if (f.getName().equalsIgnoreCase("id"))
        {
            int i=f.hashCode();
            System.out.println(i);
            f.getValue().clear();
            f.setName("");
        }
    }

现在尝试再次将其转换为xml formate：

    String xml = EntityMarshallingUtils.unmarshal(org.eclipse.jetty.server.Response.class,**fields**);
    System.out.println(xml);

抛出错误，因为对象字段不应该存在，并且无法得到我应该用什么代替字段？

我的EntityMarshallingUtils类就像：

package org.hp.qc.web.restapi.docexamples.docexamples.infrastructure;
import java.io.StringReader;
import java.io.StringWriter;
import javax.xml.bind.Marshaller;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
//import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
public class EntityMarshallingUtils {
 private EntityMarshallingUtils() {}
@SuppressWarnings("unchecked")
    public static <T> T marshal(Class<T> c, String xml) throws JAXBException     {
        T res;

        if (c == xml.getClass()) {
            res = (T) xml;
        }

        else {
            JAXBContext ctx = JAXBContext.newInstance(c);
            Unmarshaller marshaller = ctx.createUnmarshaller();
            res = (T) marshaller.unmarshal(new StringReader(xml));
        }

        return res;
    }
@SuppressWarnings("unchecked")
    public static <T> String unmarshal(Class<T> c, Object o) throws  Exception {

        JAXBContext ctx = JAXBContext.newInstance(c);
        Marshaller marshaller = ctx.createMarshaller();
        StringWriter entityXml = new StringWriter();
        marshaller.marshal(o, entityXml);

        String entityString = entityXml.toString();

        return entityString;
    }

 }

AnyOne谁可以帮我这个？