dbo.java

java web开发宝典第一章的源代码第2小节

package com.yxq.bean;

import java.sql.*;
public class DBO {
	private String URL;
	private String classname;
	private String username;
	private String password;
	
	private Connection con;
	private Statement stm;
	private ResultSet rs;
	
	public DBO(){
		URL="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_FABD01";
		classname="com.microsoft.jdbc.sqlserver.SQLServerDriver";
		username="sa";
		password="";
	}
	
	private void LoadDriver(){
		try{
			Class.forName(classname);
		}catch(ClassNotFoundException e){
			System.out.println("加载驱动程序失败！");
			e.printStackTrace();
		}
	}
	
	private Connection getCon(){
		LoadDriver();
		try{
			con=DriverManager.getConnection(URL,username,password);
		}catch(Exception e){
			System.out.println("创建数据库连接失败！");
			e.printStackTrace();
		}
		return con;
	}
	
	private Statement getStm(){
		getCon();
		try{
			stm=con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);			
		}catch(Exception e){
			System.out.println("创建Statement对象失败！");
			e.printStackTrace();
		}
		return stm;
	}
	
	public ResultSet getRs(String sql){
		if(sql==null)
			sql="";
		getStm();
		try{
			rs=stm.executeQuery(sql);			
		}catch(Exception e){
			System.out.println("查询数据库失败！");
			e.printStackTrace();
		}			
		return rs;		
	}
	public int update(String sql){
		if(sql==null)
			sql="";
		getStm();
		int i=-1;
		try{
			i=stm.executeUpdate(sql);
		}catch(Exception e){
			i=-1;
			e.printStackTrace();
		}finally{
			closed();
		}
		
		return i;
	}
	public void closed(){
		try{
			if(this.rs!=null)
				rs.close();
			if(this.stm!=null)
				stm.close();
			if(this.con!=null)
				con.close();
		}catch(Exception e){
			e.printStackTrace();
		}
	}

	public String getClassname() {
		return classname;
	}
	public void setClassname(String classname) {
		this.classname = classname;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public String getURL() {
		return URL;
	}
	public void setURL(String url) {
		URL = url;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
}