SSH 分页查询

ゝ一纸荒年。 2022-03-20 07:12 188阅读 0赞

### 前台请求json数据时 ###

### pageBean工具类 ###

public class PageBean {
    	//当前页
    	private int currentPage;
    	//每页显示条数
    	private int pageSize;
    	//查询条件
    	private DetachedCriteria detachedCriteria;
    	//总条数
    	private int total;
    	//查询结果集合
    	private List rows;
    	public int getCurrentPage() {
    		return currentPage;
    	}
    	public void setCurrentPage(int currentPage) {
    		this.currentPage = currentPage;
    	}
    	public int getPageSize() {
    		return pageSize;
    	}
    	public void setPageSize(int pageSize) {
    		this.pageSize = pageSize;
    	}
    	public DetachedCriteria getDetachedCriteria() {
    		return detachedCriteria;
    	}
    	public void setDetachedCriteria(DetachedCriteria detachedCriteria) {
    		this.detachedCriteria = detachedCriteria;
    	}
    	public int getTotal() {
    		return total;
    	}
    	public void setTotal(int total) {
    		this.total = total;
    	}
    	public List getRows() {
    		return rows;
    	}
    	public void setRows(List rows) {
    		this.rows = rows;
    	}
    	
    }

### Action ###

private int page;
    	private int rows;
    	
    	
    
    	public void setPage(int page) {
    		this.page = page;
    	}
    
    	public void setRows(int rows) {
    		this.rows = rows;
    	}
    
    
        public String pageQuery() throws IOException{
    		PageBean pageBean = new PageBean();
    		pageBean.setCurrentPage(page);
    		pageBean.setPageSize(rows);
    		//离线查询对象
    		DetachedCriteria detachedCriteria = DetachedCriteria.forClass(Staff.class);
    		pageBean.setDetachedCriteria(detachedCriteria);
    		staffService.pageQuery(pageBean);
    		
    		JsonConfig jsonConfig = new JsonConfig();
    		jsonConfig.setExcludes(new String[]{"currentPage","detachedCriteria","pageSize"});
    		String json = JSONObject.fromObject(pageBean, jsonConfig).toString();
                    //返回json
    		ServletActionContext.getResponse().setContentType("text/json;charset=utf-8");
    		ServletActionContext.getResponse().getWriter().write(json);
    		return NONE;
    	}

service直接调用dao

dao：

public void pageQuery(PageBean pageBean) {
    		int currentPage = pageBean.getCurrentPage();
    		int pageSize = pageBean.getPageSize();
    		DetachedCriteria detachedCriteria = pageBean.getDetachedCriteria();
    		
    		//查询total---总数据量
    		detachedCriteria.setProjection(Projections.rowCount());//指定hibernate框架sql的形式----》select count(*) from bc_staff;
    		List<Long> countList = (List<Long>) this.getHibernateTemplate().findByCriteria(detachedCriteria);
    		Long count = countList.get(0);
    		pageBean.setTotal(count.intValue());
    		
    		//查询rows---当前页需要展示的数据集合
    		detachedCriteria.setProjection(null);//指定hibernate框架发出sql的形式----》select * from bc_staff;
    		int firstResult = (currentPage - 1) * pageSize;
    		int maxResults = pageSize;
    		List rows = this.getHibernateTemplate().findByCriteria(detachedCriteria, firstResult, maxResults);
    		pageBean.setRows(rows);
    	}