Java后台进行分页参数类封装

http://localhost:8088/user/userInfoBySystemCd?pageNum=10&pageSize=1

/**
 * 分页参数封装类
 */
public class PageParam {

    private Integer pageNum;// 当前页面
    private Integer pageSize;// 页面大小

    public static final int DEFAULT_PAGE_NUM = 0; // 默认页面
    public static final int DEFAULT_PAGE_SIZE = 20; // 默认分页大小
    public static final String PAGE_NUM = "pageNum";
    public static final String PAGE_SIZE = "pageSize";


    /**
     * 默认构造函数
     */
    public PageParam() {

    }

    /**
     * 构造函数,起始位置为0,默认分页大小为10.
     * 
     * @param request
     * @param
     */
    public PageParam(HttpServletRequest request) {
        // 处理分页参数
        String strPageNum = request.getParameter(PAGE_NUM);
        String strPageSize = request.getParameter(PAGE_SIZE);

        if (strPageSize != null && StringUtils.isNoneBlank(strPageSize)) {
            pageSize = Integer.parseInt(strPageSize);
        } else {
            this.pageSize = DEFAULT_PAGE_SIZE;
        }
        if (strPageNum != null && StringUtils.isNoneBlank(strPageNum)) {
            this.pageNum = Integer.parseInt(strPageNum) < 1 ? 0 :((Integer.parseInt(strPageNum) - 1)*pageSize);//如果传入参数小于1则默认为0
        } else {
            this.pageNum = DEFAULT_PAGE_NUM;
        }
    }


    public Integer getPageNum() {
        return pageNum;
    }

    public void setPageNum(Integer pageNum) {
        this.pageNum = pageNum;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    @Override
    public String toString() {
        return "PageParam [pageNum=" + pageNum + ", pageSize=" + pageSize + "]";
    }

}