使用JAXBContext 设置xml节点属性

时间:2021-11-13 05:09:05

JAXBContext 设置xml节点属性

在使用JAXBContext将javaBean转化为xml时

会出现这样的需求:

?
1
2
3
<xml version="2.0">
    ....
</xml>

那么xml节点里的属性值version需要怎么设置

使用@XmlAttribute标签即可,如下代码。

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
@XmlRootElement(name = "Xml")
@XmlAccessorType(XmlAccessType.FIELD)
public class RequestBean{
 
    @XmlAttribute(name = "version") //设置节点属性
    private String version;
    private Body body;        
    @XmlElement(name = "sign"//设置子节点
    private String sign;
    //省略封装
}
 
@XmlRootElement(name = "Body")
@XmlAccessorType(XmlAccessType.FIELD)
public class Body{
    ...
}

最终得到的xml文件大致为:

?
1
2
3
4
5
6
7
8
9
<Xml version="2.0">
    <sign>111111</sign>
    <Body>
 <Amount>111</Amount>
 <Fee>fee</Fee>
 <PayerName>payname</PayerName>
 <AccountType>accountType</AccountType>
    </Body>
</Xml>

JAXBContext解析XML集合对象

@XmlElementWrapper 为数组元素或集合元素定义一个父节点。

如,类中有一元素为List items,若不加此注解,该元素将被映射为

?
1
2
<items>...</items>
<items>...</items>

这种形式,此注解可将这个元素进行包装,如:

?
1
2
3
@XmlElementWrapper(name="items")
@XmlElement(name="item")
public List items;

将会生成这样的XML样式:

?
1
2
3
4
<items>
    <item>...</item>
    <item>...</item>
</items>

Demo如下:

实体类一(定义一个被包含的子项Item):

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
package org.ywzn.po;
import javax.xml.bind.annotation.XmlAttribute;
public class Item {
 private String infoType;
 private String nodeId;
 private String resultCode;
 private String resultString;
 public Item() {
  super();
 }
 
 public Item(String infoType, String nodeId, String resultCode,
   String resultString) {
  super();
  this.infoType = infoType;
  this.nodeId = nodeId;
  this.resultCode = resultCode;
  this.resultString = resultString;
 }
 
 @XmlAttribute(name = "InfoType")
 public String getInfoType() {
  return infoType;
 }
 
 public void setInfoType(String infoType) {
  this.infoType = infoType;
 }
 
 public String getNodeId() {
  return nodeId;
 }
 
 public void setNodeId(String nodeId) {
  this.nodeId = nodeId;
 }
 
 public String getResultCode() {
  return resultCode;
 }
 
 public void setResultCode(String resultCode) {
  this.resultCode = resultCode;
 }
 
 public String getResultString() {
  return resultString;
 }
 
 public void setResultString(String resultString) {
  this.resultString = resultString;
 }
}

实体类二(定义一个有List集合的实体类):

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
package org.ywzn.po;
import java.util.List;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementWrapper;
import javax.xml.bind.annotation.XmlRootElement;
 
@XmlRootElement
public class Message {
 private String version;
 private Head head;
 private List<Item> items;
 @XmlAttribute(name="version")
 public String getVersion() {
  return version;
 }
 
 public void setVersion(String version) {
  this.version = version;
 }
 
 @XmlElement(name="Head")
 public Head getHead() {
  return head;
 }
 
 public void setHead(Head head) {
  this.head = head;
 }
 
 public List<Item> getItems() {
  return items;
 }
 
 @XmlElementWrapper(name="Items")
 @XmlElement(name="Item")
 public void setItems(List<Item> items) {
  this.items = items;
 
}

测试方法:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
package org.ywzn.main;
import java.util.ArrayList;
import java.util.List;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import org.ywzn.po.Head;
import org.ywzn.po.Item;
import org.ywzn.po.Message;
import org.ywzn.po.Parameters;
import org.ywzn.po.Room;
 
public class Java2XMLMany {
 public static void main(String[] args) {
  // <?xml version='1.0' encoding='UTF-8' standalone='no' ?> <Message
  // version='1.0'><Header Time='2015-05-22 10:34:27' MessageType='LOGIN'
  // BusinessId='B730EB39-CEFF-4a38-B633-D8936EB8AEF7' SessionId='936'
  // /><Parameters> <items Sum='1' Offset='1' Cur='1'> <item
  // Infotype='LogUser'> <PassWord
  // >D41D8CD98F00B204E9800998ECF8427E</PassWord></item> </items>
  // </Parameters> </Message>
 
  // TODO Auto-generated method stub
  Item item = new Item("LOGIN","789", "xxx","xxx");
  List<Item> list = new ArrayList<Item>();
  list.add(item);
  Head head = new Head("2015-05-21 16:46:14", "LOGIN", "8D24CE2B-5");
  Parameters parameters = new Parameters(list);
  // Message message = new Message(head,"1.0",parameters);
  Message message = new Message();
  message.setVersion("1.0");
  message.setHead(head);
  message.setItems(list);
  try {
   JAXBContext context = JAXBContext.newInstance(Message.class);
   Marshaller createMarshaller = context.createMarshaller();
   createMarshaller
     .setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);// 是否格式化生成的xml串
 
   createMarshaller.marshal(message, System.out);
  } catch (JAXBException e) {
   e.printStackTrace();
  }
 }
 
}

输出:

?
1
2
3
4
5
6
7
8
9
10
11
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<message version="1.0">
    <Head businessId="8D24CE2B-5" MessageType="LOGIN" Time="2015-05-21 16:46:14"/>
    <Items>
        <Item InfoType="LOGIN">
            <nodeId>789</nodeId>
            <resultCode>xxx</resultCode>
            <resultString>xxx</resultString>
        </Item>
    </Items>
</message>

以上为个人经验,希望能给大家一个参考,也希望大家多多支持服务器之家。

原文链接:https://blog.csdn.net/Dawn_Bells/article/details/81908275