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  • 查询数据的分页

    在Mysql数据库中用的是   limit n,m    n代表着从第几条显示,m为显示的显示多少行

     数据类:成员变量,成员方法(get set)

    public class Fruit {
    	private String daihao;
    	private String shuiguoming;
    	private double danjia;
    	private String chandi;
    	private int kucun;
    	private String tupian;
    	public String getDaihao() {
    		return daihao;
    	}
    	public void setDaihao(String daihao) {
    		this.daihao = daihao;
    	}
    	public String getShuiguoming() {
    		return shuiguoming;
    	}
    	public void setShuiguoming(String shuiguoming) {
    		this.shuiguoming = shuiguoming;
    	}
    	public double getDanjia() {
    		return danjia;
    	}
    	public void setDanjia(double danjia) {
    		this.danjia = danjia;
    	}
    	public String getChandi() {
    		return chandi;
    	}
    	public void setChandi(String chandi) {
    		this.chandi = chandi;
    	}
    	public int getKucun() {
    		return kucun;
    	}
    	public void setKucun(int kucun) {
    		this.kucun = kucun;
    	}
    	public String getTupian() {
    		return tupian;
    	}
    	public void setTupian(String tupian) {
    		this.tupian = tupian;
    	}
    	
    	
    }
    

    访问类:

      1.驱动类:

    import java.sql.*;
    
    
    public class DBConn {
    
        public static String qd="com.mysql.jdbc.Driver";
        public static String jdbc="jdbc:mysql://127.0.0.1:3306/mydb";
        public static String uid="root";
        public static String pwd="";
        
        public static Connection getconnection () throws Exception{
            Class.forName(qd);
            Connection conn=DriverManager.getConnection(jdbc,uid,pwd);
            
            return conn;
            
        }
    }

        2.访问数据类

    import java.sql.*;
    import java.util.*;
    
    import com.maya.shuju.*;
    
    
    public class FruitDao {
        private Connection conn;
        private ResultSet re;
        private PreparedStatement stat;
        
        public FruitDao() throws Exception {
        
            conn=DBConn.getconnection();
        }
        
        public ArrayList<Fruit> select(int m, int n  ) throws Exception{
            ArrayList<Fruit> list = new ArrayList<Fruit>();
            String sql="select * from fruit limit ?,?";
            stat=conn.prepareStatement(sql);
            stat.setInt(1, (m-1)*n);    //(m-1)*n,     m是跳过的行数,-1  再乘n   就是页数对应的行数
            stat.setInt(2, n);
            re=stat.executeQuery();
            while (re.next()){
                Fruit tada = new Fruit();
                
                tada.setDaihao(re.getString(1));
                tada.setShuiguoming(re.getString(2));
                tada.setDanjia(re.getDouble(3));
                tada.setChandi(re.getString(4));
                tada.setKucun(re.getInt(5));
                tada.setTupian(re.getString(6));
                list.add(tada);
            }
    
            return list;
        }
    
        
    }

    界面类:

    import java.util.*;
    
    import com.maya.fangwen.*;
    import com.maya.shuju.*;
    
    public class JieMian {
    
        public static void main(String[] args) throws Exception {
            
            Scanner sc=new Scanner(System.in);
            System.out.println("请输入页数");
            int ys=Integer.parseInt(sc.nextLine());
            System.out.println("请输入每页几条");
            int ts=Integer.parseInt(sc.nextLine());
        
            
            ArrayList<Fruit> s=new FruitDao().select(ys, ts);
        
            for (int i=0;i<s.size();i++){
                System.out.println(s.get(i).getShuiguoming());
            }
            
    
        }
    
    }
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  • 原文地址:https://www.cnblogs.com/zhaotiancheng/p/6262622.html
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