使用BeanWrapperFieldExtractor从子类对象获取属性

import org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor;
import org.springframework.batch.item.file.transform.FieldExtractor;

public class Example {

    public static void main(String[] args) {
        // 假设有一个父类和一个子类
        ParentClass parent = new ParentClass();
        parent.setParentField("Parent Value");

        ChildClass child = new ChildClass();
        child.setParentField("Parent Value");
        child.setChildField("Child Value");

        // 创建 BeanWrapperFieldExtractor 实例
        FieldExtractor<ChildClass> extractor = new BeanWrapperFieldExtractor<>();
        extractor.setNames(new String[]{"parentField", "childField"});

        // 提取属性值
        Object[] values = extractor.extractSource(child);

        // 打印提取的值
        for (Object value : values) {
            System.out.println(value);
        }
    }
}

class ParentClass {
    private String parentField;

    public String getParentField() {
        return parentField;
    }

    public void setParentField(String parentField) {
        this.parentField = parentField;
    }
}

class ChildClass extends ParentClass {
    private String childField;

    public String getChildField() {
        return childField;
    }

    public void setChildField(String childField) {
        this.childField = childField;
    }
}

// 使用反射访问私有属性（不推荐）
Field field = child.getClass().getDeclaredField("privateField");
field.setAccessible(true);
Object value = field.get(child);