Question

如何在执行编组程序时解决异常“方法编组（Book，＆gt; FileWriter）未定义类型Pool.Marshaller”。

 import java.io.FileWriter;
 import java.util.ArrayList;
 import java.util.List;

 import com.sun.xml.internal.ws.util.Pool.Marshaller;

 public class BookMarshaller {
 public static void main(String[] args) {
  try {
  Book book = new Book("9780312347482", "Power Play", "Joseph Finder");
  FileWriter writer = new FileWriter("book.xml");
  Marshaller.marshal(book, writer);

  List book2Authors = new ArrayList();
  book2Authors.add("Douglas Preston");
  book2Authors.add("Lincoln Child");
  Book book2 = new Book("9780446618502", "The Book of the Dead",
                        book2Authors);
  writer = new FileWriter("book2.xml");
  Marshaller.marshal(book2, writer);

  } catch (Exception e) {
  System.err.println(e.getMessage());
  e.printStackTrace(System.err);
  }
  }
  }

Answer 1

您正在使用com.sun.xml.ws.util.Pool.Marshaller - 我想，您想要使用javax.xml.bind.Marshaller。验证更改您的import语句！

Pool.Marshaller没有marshal方法。

和 - 就像skaffman在他的评论中指出的那样 - marshal不是一个静态方法 - 你需要一个JAXB上下文来创建一个marshaller实例来编组图书实例。

Answer 2

我建议您将代码更改为以下内容：

package forum9736839;

import java.io.FileWriter;
import java.util.*;
import javax.xml.bind.*;

public class BookMarshaller {
    public static void main(String[] args) {
        try {
            JAXBContext jc = JAXBContext.newInstance(Book.class);
            Marshaller marshaller = jc.createMarshaller();

            Book book = new Book("9780312347482", "Power Play", "Joseph Finder");
            FileWriter writer = new FileWriter("book.xml");
            marshaller.marshal(book, writer);

            List book2Authors = new ArrayList();
            book2Authors.add("Douglas Preston");
            book2Authors.add("Lincoln Child");
            Book book2 = new Book("9780446618502", "The Book of the Dead",
                    book2Authors);
            writer = new FileWriter("book2.xml");
            marshaller.marshal(book2, writer);

        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace(System.err);
        }
    }

}

执行编组程序时出错？

2 个答案: