自定义注解结合pageHelper实现分页

import cn.hutool.core.convert.Convert;
import cn.hutool.core.lang.Validator;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.gxuwz.common.AjaxResult;
import com.gxuwz.utils.ServletUtils;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
import java.util.List;
import static com.gxuwz.common.Constants.PAGE_NUM;
import static com.gxuwz.common.Constants.PAGE_SIZE;


@Component
@Aspect
public class PageAspect {

    @Pointcut("@annotation(com.gxuwz.annotation.EnablePaging)")
    public void annotationPointcut() {
    }
	// 实现分页只需该方法即可
    @Around("annotationPointcut()")
    public AjaxResult doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        Integer pageNum = ServletUtils.getParameterToInt(PAGE_NUM);
        Integer pageSize = ServletUtils.getParameterToInt(PAGE_SIZE);
        if (Validator.isNotNull(pageNum) && Validator.isNotNull(pageSize)) {
            // 设置分页
            PageHelper.startPage(pageNum, pageSize).setReasonable(true);
        }
        AjaxResult ajax = (AjaxResult) joinPoint.proceed();
        ajax.put("total",new PageInfo<>((List