如何在Java8和ModelMapper中使用显式映射？

import org.modelmapper.ModelMapper;
import org.modelmapper.PropertyMap;

public class Main {
    public static void main(String[] args) {
        // 创建源对象和目标对象
        SourceObject source = new SourceObject("John", "Doe");
        TargetObject target = new TargetObject();

        // 创建ModelMapper对象
        ModelMapper modelMapper = new ModelMapper();

        // 创建映射规则
        PropertyMap<SourceObject, TargetObject> propertyMap = new PropertyMap<SourceObject, TargetObject>() {
            protected void configure() {
                map().setFirstName(source.getFirstName());
                map().setLastName(source.getLastName());
            }
        };

        // 添加映射规则
        modelMapper.addMappings(propertyMap);

        // 执行映射
        modelMapper.map(source, target);

        // 输出目标对象属性
        System.out.println(target.getFirstName()); // 输出：John
        System.out.println(target.getLastName()); // 输出：Doe
    }
}

class SourceObject {
    private String firstName;
    private String lastName;

    public SourceObject(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    // 省略getter和setter方法
}

class TargetObject {
    private String firstName;
    private String lastName;

    // 省略getter和setter方法
}