通过注解和反射，比较两个对象，需要校验某些字段是否相同，如果不同，中文字段名称和属性值对比结果（直接上代码）

实际开发中，存在比较两个对象，需要校验某些字段是否相同，如果不同，需返回前端页面名称和属性值
比较笨的办法就是，对两个对象需要判断的属性一一进行对比，如果只有几个属性值需要对比，可以满足，但是字段值过多就不使用了，也没有通用性

下面介绍利用反射机制，判断两个对象属性值是否相同

package com.fehorizon.hxtms.order.vo.demandOrder.request;

import com.fehorizon.hxtms.order.config.GetParamName;

public class Student {
    @GetParamName(value = "姓名")
    private String name;
    @GetParamName(value = "性别")
    private String gender;
    @GetParamName(value = "手机号")
    private String phone;
    @GetParamName(value = "地址")
    private String addr;

    public Student(String name, String gender, String phone, String addr) {
        this.name = name;
        this.gender = gender;
        this.phone = phone;
        this.addr = addr;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public String getAddr() {
        return addr;
    }

    public void setAddr(String addr) {
        this.addr = addr;
    }

    @Override
    public String toString() {
        return "Student";
    }
}

public static void main(String[] args) throws IllegalAccessException {
    Student student = new Student("小明", "男", "15011112222", "重庆");
    User user = new User("小", "admin", "15811112222", "北京");

    StringBuffer stringBuffer = compareTwoObject(student, user);
    System.out.println(stringBuffer);
    // 运行结果 {compare_object: =Student vs User, Student_field:phone=15011112222, User_field:phone=15811112222}
}

public static StringBuffer compareTwoObject(Object obj1, Object obj2) throws IllegalAccessException {
    StringBuffer stringBuffer = new StringBuffer();
    Class<?> clazz1 = obj1.getClass();
    Class<?> clazz2 = obj2.getClass();
    Field[] fields1 = clazz1.getDeclaredFields();
    Field[] fields2 = clazz2.getDeclaredFields();
    for (Field field1 : fields1) {
        for (Field field2 : fields2) {
            if (!field1.isAnnotationPresent(GetParamName.class)) {
                continue;
            }
            if (field1.getName().equals(field2.getName())) {
                field1.setAccessible(true);
                field2.setAccessible(true);
                if (!compareTwoObject1(field1.get(obj1), field2.get(obj2))) {
                    GetParamName annotation = field1.getAnnotation(GetParamName.class);
                    if (annotation != null) {
                        String s = ("").equals(annotation.value()) ? null : annotation.value();
                        stringBuffer.append("『"+s+"』字段:<"+field1.get(obj1).toString()+">修改为<"+field2.get(obj2).toString()+">。");
                    }
                }
            }
        }
    }
    return stringBuffer;
}
public static boolean compareTwoObject1(Object object1, Object object2) {
    if (object1 == null && object2 == null) {
        return true;
    }
    if (object1 == null && object2 != null){
        return false;
    }
    // 假如还有别的类型需要特殊判断 比如 BigDecimal, 演示，只写BigDecimal示例，其他都相似
    if (object1 instanceof BigDecimal && object2 instanceof BigDecimal) {
        if (object1 == null && object2 == null) {
            return true;
        }
        if (object1 == null ^ object2 == null) {
            return false;
        }
        return ((BigDecimal) object1).compareTo((BigDecimal) object2) == 0;
    }

    if (object1.equals(object2)) {
        return true;
    }
    return false;
}

package com.fehorizon.hxtms.order.config;

import java.lang.annotation.*;

@Target({ElementType.FIELD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
/**
 * description:
 * create time: 10:34 2020/12/2
 *
 * @return 
 */
public @interface GetParamName {
    String value();
}