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  • java(2014)实现对mysql数据库分页的代码

    package util;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.List;
    
    /**
     * @author Hongyu
     * 
     * @param <T>
     */
    public class Pagination<T> {
    	// 当前页
    	private Integer nowPage;
    	// 页面要显示信息条数
    	private Integer pageSize;
    	// 根据页面显示的条数计算总页数
    	private Integer countPage;
    	// 根据传入的数据库查询数据库中的信息的条数
    	private Integer total;
    	// 向数据库查询时的开始的下标
    	private Integer startIndex;
    	// 向数据库查询时的查询条数
    	private Integer endIndex;
    
    
    	// 将查询到的数据存放到这里
    	private List<T> rows;
    
    	public Pagination(Integer nowPage, Integer pageSize, String tableName) {
    		// 赋值
    		this.nowPage = nowPage;
    		this.pageSize = pageSize;
    
    		// 判断当前页是否合法
    		if (this.nowPage < 1) {
    			this.nowPage = 1;
    		}
    
    		// 向数据库发送查询,查询出指定表格的数据的总数
    		this.total = this.getCountSize(tableName);
    		// 计算总页数
    		this.countPage = this.total % this.pageSize == 0 ? this.total
    				/ this.pageSize : this.total / this.pageSize + 1;
    
    		if (this.nowPage > this.countPage) {
    			this.nowPage = this.countPage;
    		}
    
    		//System.out.println("pagenation中的nowPage==========" + this.nowPage);
    		// 计算出开始的记录下标,和每页要显示的条数
    
    		if (this.nowPage == 0) {
    			this.startIndex = this.nowPage * this.pageSize;
    			this.endIndex = this.pageSize;
    		} else {
    			this.startIndex = (this.nowPage - 1) * this.pageSize;
    			this.endIndex = this.pageSize;
    		}
    
    		/*System.out.println(this.startIndex + "======pagenation中的开始和结束========"
    				+ this.endIndex+"====================总页数"+countPage);
    */
    	}
    
    	// 根据提供的表名向数据库发送请求,计算指定数据表中的数据总条数
    	public Integer getCountSize(String tableName) {
    		int countRecord = 0;
    		String sql = "select count(*) as c from " + tableName;
    		Connection conn = JdbcUtil.getConn();
    		PreparedStatement pstmt = null;
    		ResultSet rs = null;
    		try {
    			pstmt = conn.prepareStatement(sql);
    			rs = pstmt.executeQuery();
    			if (rs.next()) {
    				countRecord = rs.getInt("c");
    			}
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} finally {
    			JdbcUtil.release(rs, pstmt);
    		}
    		return countRecord;
    	}
    
    	public List<T> getRows() {
    		return rows;
    	}
    
    	public void setRows(List<T> rows) {
    		this.rows = rows;
    	}
    
    	public Integer getStartIndex() {
    		return startIndex;
    	}
    
    	public Integer getEndIndex() {
    		return endIndex;
    	}
    
    	public Integer getTotal() {
    		return total;
    	}
    	
    
    
    }
    


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  • 原文地址:https://www.cnblogs.com/fuhaots2009/p/3503045.html
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