jdbc中分页技术结合sql语句实现

package jdbcDay03;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Scanner;
public class TestPage {
	public static void main(String[] args) {
//		getResult(20,10);
//		getPage(10,5);			//每页是10条。，，第5页
		int page=0;
		System.out.println("你输入的页码是：");
		Scanner ss=new Scanner(System.in);  
		page=ss.nextInt();
		getpageSimple(10,page);
//		System.out.println(getTotalNumber());
	}
	public static void getResult(int m,int n){		//输出指定从m到n的记录
		String sql="select id ,user_id,login_time,logout_time,rn "+
		"from (select id,user_id,login_time,logout_time,rownum rn from mytemp where rownum<?)"
		+"where rn>=?";
		try {
			Connection conn=ConnectionUtils.openConnection();
			PreparedStatement pstmt=conn.prepareStatement(sql);
			pstmt.setInt(1,m);
			pstmt.setInt(2, n);
			ResultSet rs=pstmt.executeQuery();
			while(rs.next()){
				String line=rs.getString(1)+"\t"+rs.getString(2)+"\t"+rs.getString(5);
				System.out.println(line);
			}
			pstmt.close();
			conn.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	public static void getPage(int pageSize,int page){
		int  from=(page-1)*pageSize+1;
		int to=from+pageSize;
		String sql="select id ,user_id,login_time,logout_time,rn "+
		"from (select id,user_id,login_time,logout_time,rownum rn from mytemp where rownum<=?)"
		+"where rn>=?";
		try {
			Connection conn=ConnectionUtils.openConnection();
			PreparedStatement pstmt=conn.prepareStatement(sql);
			pstmt.setInt(1, to);
			pstmt.setInt(2, from);
			ResultSet rs=pstmt.executeQuery();
			while(rs.next()){
				String line=rs.getString(1)+"\t"+rs.getString(2)+"\t"+rs.getString(5);
				System.out.println(line);
			}
			pstmt.close();
			conn.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	public static void getpageSimple(int pageSize,int page){
		int totalPage=0;				//总共有多少页数
		int totalNumber=getTotalNumber();
		
		if(totalNumber%pageSize==0){
			totalPage=totalNumber/pageSize;
		}else{
			totalPage=totalNumber/pageSize+1;
		}
		if(page>totalPage){
			page=totalPage;
		}else if(page<1){
			page=1;
		}
		int from =(page-1)*pageSize+1;
		int to=from +pageSize;
		getResult(to,from);
	}

	public static int getTotalNumber(){	//获得mytemp中共有多少条记录
		String  sql="select Count(*) num from mytemp";
		int n=-1;
		try {
			Connection conn=ConnectionUtils.openConnection();
			Statement stmt=conn.createStatement();
			ResultSet rs=stmt.executeQuery(sql);
			rs.next();
			n=rs.getInt("num");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return n;
	}
}