java 属性复制为空属性不复制

工具类

package com.jiayou.peis.common.core.util;

import org.springframework.beans.BeanUtils;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;

import java.util.HashSet;
import java.util.Set;

/**
 * 自定义属性复制
 */
public class MyBeanUtils extends org.springframework.beans.BeanUtils{

    private static String[] getNullPropertyNames (Object source) {
        final BeanWrapper src = new BeanWrapperImpl(source);
        java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();

        Set<String> emptyNames = new HashSet<>();
        for(java.beans.PropertyDescriptor pd : pds) {
            Object srcValue = src.getPropertyValue(pd.getName());
            if (srcValue == null||"".equals(srcValue)){
                emptyNames.add(pd.getName());
            }
        }
        String[] result = new String[emptyNames.size()];
        return emptyNames.toArray(result);
    }

    /**
     *
     * 忽略null和空值
     * src：数据对象
     * target：目标对象
     * 描述：把src对象不为null和空字符串的对象赋值给target对象
     *
     * */
    public static void copyPropertiesIgnoreNull(Object src, Object target){
        BeanUtils.copyProperties(src, target, getNullPropertyNames(src));
    }

    public static void main(String[] args) {
        Student source=new Student();
        source.setName("李四");
        source.setAge(30);
        source.setSex("男");
        source.setNation(null);

        Student target=new Student();
        target.setName("晓芳");
        target.setAge(20);
        target.setSex("女");
        target.setNation("苗族");

        /**属性复制为空属性不复制*/
        copyPropertiesIgnoreNull(source,target);
        System.out.println(target);

        /**复制全部属性（调用继承方法）*/
        copyProperties(source,target);
        System.out.println(target);
    }
}

Sudent.java

package com.jiayou.peis.common.core.util;

import lombok.Data;

@Data
public class Student {
    private String name;
    private Integer age;
    private String sex;
    private String nation;
}