Java之XML操作：从XML中直接获取数据

　　本文介绍如何将数据记录在XML文件中，然后通过DOM4J直接从XML中读取到数据。

依赖包：

<dependency>
    <groupId>dom4j</groupId>
    <artifactId>dom4j</artifactId>
    <version>1.6.1</version>
</dependency>

工具类代码：

 1 package testTraffic.utils;
 2
 3 import org.dom4j.Document;
 4 import org.dom4j.DocumentException;
 5 import org.dom4j.Element;
 6 import org.dom4j.io.SAXReader;
 7 import java.io.File;
 8 import java.io.IOException;
 9 import java.io.InputStream;
10 import java.net.URISyntaxException;
11 import java.util.ArrayList;
12 import java.util.LinkedHashMap;
13 import java.util.List;
14 import java.util.Map;
15
16 /**
17  * XmlUtils class
18  *
19  * @author gongxingrui
20  * @date 2018-12-07
21  **/
22 public class XmlUtils {
23
24
25     public static Document readXml(String filePath) throws DocumentException {
26         return readXml(new File(filePath));
27     }
28
29
30     public static Document readXml(File file) throws DocumentException {
31         SAXReader reader = new SAXReader();
32         return reader.read(file);
33     }
34
35     public static Document readXml(InputStream inputStream) throws DocumentException {
36         SAXReader reader = new SAXReader();
37         return reader.read(inputStream);
38     }
39
40
41     public static Document readXmlFromResources(String resource) throws DocumentException, IOException, URISyntaxException {
42         SAXReader reader = new SAXReader();
43         return reader.read(ResourcesUtils.getResourceAsFile(resource));
44     }
45
46
47     public static String getAttribute(Element element, String attrName) {
48         return element.attributeValue(attrName);
49     }
50
51     public static String getText(Element element) {
52         return element.getText();
53     }
54
55     public static List<Element> getElements(Element element, String tagName) {
56         return element.elements(tagName);
57     }
58
59     /**
60      * 根据节点名称获取子节点数据
61      */
62     public static String getElementText(String resource, String qName) throws Exception {
63         Element root = readXmlFromResources(resource).getRootElement();
64         String text = root.elementText(qName);
65         return text.trim();
66     }
67
68     /**
69      * 根据节点名称获取子节点的子节点数据
70      */
71     public static String getElementText(String resource, String qName, String SubQName) throws Exception {
72         Element root = readXmlFromResources(resource).getRootElement();
73         String text = root.element(qName).elementText(SubQName);
74         return text.trim();
75     }
76
77     /**
78      * 根据节点名称获取子节点的子节点的数据列表
79      */
80     public static List<String> getElementTextList(String resource, String qName) throws Exception {
81         List<Element> elementList = readXmlFromResources(resource).getRootElement().element(qName).elements();
82         List<String> list = new ArrayList<>();
83         for (Element e : elementList) {
84             list.add(e.getTextTrim());
85         }
86         return list;
87     }
88
89
90 }

测试代码：

    @Test
    public void testXML6() throws Exception {
        String path2 = "shelby/data/sql/demo/sql2.xml";
        String s = XmlUtils.getElementText(path2, "insert_1");
        logger.info(s);

        List<String> list = XmlUtils.getElementTextList(path2, "del_group");
        logger.info(list);

        String s2 = XmlUtils.getElementText(path2, "del_group_2", "del_2");
        logger.info(s2);
    }   

测试结果：

2019-01-28 16:13:14.746 INFO  testTraffic.testDemo.testXmlDemo testXML6 : insert into `t_admin_user` (`id`, `user_name`, `user_password`, `del_flag`, `create_time`, `update_time`)
        VALUES( null,‘testuser‘,‘testuser123‘,‘0‘,‘2019-01-21 19:43:58‘,‘2019-01-22 19:44:03‘);
2019-01-28 16:13:14.763 INFO  testTraffic.testDemo.testXmlDemo testXML6 : [delete from t_admin_user WHERE user_name = ‘testuser‘;, delete from t_admin_user WHERE user_name = ‘testuser2‘;]
2019-01-28 16:13:14.768 INFO  testTraffic.testDemo.testXmlDemo testXML6 : delete from t_admin_user WHERE user_name = ‘testuser2‘;

Process finished with exit code 0

XML文档：

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <mybatisGroup id="预置数据语句">
 3     <del_1 id="del_1" type="delete">
 4         delete from t_admin_user WHERE user_name = ‘testuser‘;
 5     </del_1>
 6     <del_2 id="del_2" type="delete">
 7         delete from t_admin_user WHERE user_name = ‘testuser2‘;
 8     </del_2>
 9     <insert_1 id="insert_1" type="insert">
10         insert into `t_admin_user` (`id`, `user_name`, `user_password`, `del_flag`, `create_time`, `update_time`)
11         VALUES( null,‘testuser‘,‘testuser123‘,‘0‘,‘2019-01-21 19:43:58‘,‘2019-01-22 19:44:03‘);
12     </insert_1>
13
14     <del_group>
15         <statement>
16             delete from t_admin_user WHERE user_name = ‘testuser‘;
17         </statement>
18         <statement>
19             delete from t_admin_user WHERE user_name = ‘testuser2‘;
20         </statement>
21     </del_group>
22
23     <del_group_2>
24         <del_1>
25             delete from t_admin_user WHERE user_name = ‘testuser‘;
26         </del_1>
27         <del_2>
28             delete from t_admin_user WHERE user_name = ‘testuser2‘;
29         </del_2>
30         <del_3>
31             delete from t_admin_user WHERE user_name = ‘testuser3‘;
32         </del_3>
33     </del_group_2>
34
35 </mybatisGroup>

原文地址：https://www.cnblogs.com/gongxr/p/10330694.html