java - 读取配置文件

夜深人静学算法2024-04-08 9:03

文章目录

[1. properties](#1. properties)
[2. XML](#2. XML)
- [(1) dom4j](#(1) dom4j)
- [(2) XPath](#(2) XPath)

1. properties

java 复制代码

	// 创建properties对象用于读取properties文件
	Properties properties = new Properties();
        properties.load(new FileReader("src/main/resources/test.properties"));
        String name = properties.getProperty("name");
        String age = properties.getProperty("age");
        System.out.println(name);
        System.out.println(age);

2. XML

(1) dom4j

maven坐标

xml 复制代码

    <dependency>
      <groupId>dom4j</groupId>
      <artifactId>dom4j</artifactId>
      <version>1.1</version>
    </dependency>

java 复制代码

		// 获取解析器对象
        SAXReader xmlReader = new SAXReader();
		// 获取xml文件
        Document student = xmlReader.read(new File("student.xml"));

        Element root = student.getRootElement();// 获取根标签
        List<Element> elements = root.elements();// 获取根标签中的所有标签
		// 获取第一个元素的name标签的值
        String name = elements.get(0).element("name").getText();
        // 获取第一个元素的age标签的值
        String age = elements.get(0).element("age").getText();
        System.out.println(name);
        System.out.println(age);

(2) XPath

使用路径表达式进行解析

xml 复制代码

// 获取解析器对象
        SAXReader xmlReader = new SAXReader();

        Document student = xmlReader.read(new File("src\\main\\resources\\student.xml"));
        // 获取一个
        Node node = student.selectSingleNode("/students/student/name");
        System.out.println(node.getText());
        //获取多个
        List<Element> list = student.selectNodes("/students/student/*");
        for (Element element : list) {
            System.out.println(element.getText());
        }