JAXB - SAXParseException 找不到元素的声明

使用JAXB（Java Architecture for XML Binding）时，有时会遇到SAXParseException异常，提示找不到元素的声明。这个问题通常是由于XML文件中的元素名称与Java类中的字段名称不匹配引起的。

xml
    John Doe
    20
    Male

java
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement
public class Student {
    private String name;
    private int age;
    private String gender;
    public String getName() {
        return name;
    }
    @XmlElement
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    @XmlElement
    public void setAge(int age) {
        this.age = age;
    }
    public String getGender() {
        return gender;
    }
    @XmlElement
    public void setGender(String gender) {
        this.gender = gender;
    }
}

java
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import java.io.File;
public class Main {
    public static void main(String[] args) {
        try {
            File file = new File("student.xml");
            JAXBContext jaxbContext = JAXBContext.newInstance(Student.class);
            Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
            Student student = (Student) jaxbUnmarshaller.unmarshal(file);
            System.out.println("Name: " + student.getName());
            System.out.println("Age: " + student.getAge());
            System.out.println("Gender: " + student.getGender());
        } catch (JAXBException e) {
            e.printStackTrace();
        }
    }
}