记录同一个类字段值变化日志工具类

1.单个变量值前后工具类代码

1.1 自定义注解

@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface ForUpdate {
    String fieldName() default "";
}

1.2 工具方法

日志示例：
修改年龄"10"为"20";

具体日志格式不同，小伙伴们可以自行修改builder。

 /**
     * 获取变更内容
     *
     * @param beforeBean                        更改前的Bean
     * @param afterBean                         更改后的Bean
     * @param <T>修改姓名"小白"为"小黑";修改年龄"10"为"20";
     * @return
     */
    public static <T> String getSingleFields(T beforeBean, T afterBean) {
        Field[] fields = beforeBean.getClass().getDeclaredFields();
        StringBuilder builder = new StringBuilder();
        for (Field field : fields) {
            field.setAccessible(true);
            if (field.isAnnotationPresent(ForUpdate.class)) {
                try {
                    Object newValue = field.get(beforeBean);
                    Object oldValue = field.get(afterBean);
                    if (!Objects.equals(newValue, oldValue)) {
                        builder.append("修改");
                        builder.append(field.getAnnotation(ForUpdate.class).fieldName()); //获取字段名称
                        builder.append("\"");
                        builder.append(newValue);
                        builder.append("\"");
                        builder.append("为\"");
                        builder.append(oldValue);
                        builder.append("\";");
                    }
                } catch (Exception e) {
                    log.error(e.getMessage());
                }
            }
        }
        return builder.toString();
    }

2. 测试验证

2.1 test

   @Test
    public void singleTest() {
        Bean beforeBean = new Bean(1L, "男", "小白");
        Bean afterBean = new Bean(1L, "女", "张飞");
        String msg = getSingleFields(beforeBean, afterBean);
        System.out.println(msg);
    }

2.2 运行结果：

修改性别"男"为"女";修改姓名"小白"为"张飞";