userdao.java

在学校做的第一个jsp专周论坛,用了些ajax技术.

package com.dao;

import java.sql.*;
import java.util.ArrayList;

import com.data.*;
import com.db.*;
import com.tools.Pageable;

public class UserDao {
	
//	此函数没有用到过
    public static User getUserDao(int user_id){
    	String sql="select * from user where user_id="+user_id;
        Connection con=DataProcess.getConnection(); //连接
        Statement pStmt=null;
    	ResultSet rs=null;
    	User user=new User();
        try{
        	pStmt=con.createStatement();
        	rs=pStmt.executeQuery(sql);//查询
        	if(rs.next()){
        		String username=rs.getString("username");
        		String userpassword=rs.getString("userpassword");
        		String useremail=rs.getString("useremail");
    			String userhomepage=rs.getString("userhomepage");
    			String userhpname=rs.getString("userhpname");
    			String userbirthday=rs.getString("userbirthday");
    			String usersex=rs.getString("usersex");
    			String comefrom=rs.getString("comefrom");
    			int userclass=rs.getInt("userclass");
    			String usersign=rs.getString("usersign");
    			String dateendtime=rs.getString("dateendtime");
    			
    			user.setUsername(username);
    			user.setUserpassword(userpassword);
    			user.setUseremail(useremail);
    			
    			user.setUserhpname(userhpname);
    		
    			user.setUsersex(usersex);
    			
    			user.setUserclass(userclass);
    			
    			
    			user.setUser_id(user_id);
        	}
        	
        	return user;//返回结果
        }catch(Exception e){
        	e.printStackTrace();
        	return null;
        }finally{
        	try {
				rs.close();
			    pStmt.close();
        	    con.close();
        	} catch (SQLException e) {
				
				e.printStackTrace();
			}
        }
    }
//  此函数没有用到过
    public static User getUserDao(String username){
    	
    	String sql="select * from user where username='"+username+"'";
        Connection con=DataProcess.getConnection(); //连接
        Statement pStmt=null;
    	ResultSet rs=null;
    	User user=null;
    	
    	try{
    		
    		pStmt=con.createStatement();
    		rs=pStmt.executeQuery(sql);
    		//只有一条
    		if(rs.next()){
    			user=new User();
    			//结果集(rs)取数据
        		int user_id=rs.getInt("user_id");
        		String userpassword=rs.getString("userpassword");
        		String useremail=rs.getString("useremail");
    			
    			String userhpname=rs.getString("userhpname");
    			
    			String usersex=rs.getString("usersex");
    			
    			int userclass=rs.getInt("userclass");
    			
    			
    			//存到user返回
    			user.setUsername(username);
    			user.setUserpassword(userpassword);
    			user.setUseremail(useremail);
    		
    			user.setUserhpname(userhpname);
    			
    			user.setUsersex(usersex);
    			
    			user.setUserclass(userclass);
    			
    			
    			user.setUser_id(user_id);
        	}
        	
        	return user;//返回
        }catch(Exception e){
        	e.printStackTrace();
        	return null;
        }finally{
        	try {
				rs.close();
			    pStmt.close();
        	    con.close();
        	} catch (SQLException e) {
				
				e.printStackTrace();
			}
        }
    }
    //查询用户结果
    public static ArrayList getUserDao(String sql,int page,int pageSize){
    	ArrayList al=new ArrayList();
    	Connection con=DataProcess.getConnection();//连接
    	PreparedStatement pStmt=null;
    	ResultSet rs=null;
    	try{
    		pStmt=con.prepareStatement(sql,ResultSet.TYPE_SCROLL_INSENSITIVE,
    				                    ResultSet.CONCUR_READ_ONLY );
    		rs=pStmt.executeQuery();
    		Pageable pgb=new Pageable(rs);
    		pgb.setPageSize(pageSize);
    		//pgb.gotoPage(page);
    	    
    		rs.absolute(pgb.getRowsCount());//定位
    		int i=0;
    		User user=new User();
    		do{
    			String username=rs.getString("username");
        		String userpassword=rs.getString("userpassword");
        		String useremail=rs.getString("useremail");
    			
    			String userhpname=rs.getString("userhpname");
    			
    			String usersex=rs.getString("usersex");
    		
    			int userclass=rs.getInt("userclass");
    			
    			
    			int user_id=rs.getInt("user_id");
    			
    			user.setUsername(username);
    			user.setUserpassword(userpassword);
    			user.setUseremail(useremail);
    			
    			user.setUserhpname(userhpname);
    		
    			user.setUsersex(usersex);
    			
    			user.setUserclass(userclass);
    			
    		
    			user.setUser_id(user_id);
    			al.add(user);
    		}while(rs.next() && i<pgb.getCurrentPageRowsCount());
    		return al;//返回结果
    		
    		
    	}catch(Exception e){
    		e.printStackTrace();
    		return null;
    	}
    	finally{
    		try {
				rs.close();
			    pStmt.close();
        	    con.close();
        	} catch (SQLException e) {
				e.printStackTrace();
			}
    	}
    	
    	
    } 
}