dbconnect.java

一个网上书店的例子

package myshop;
import java.sql.*;
public class DbConnect {
	String user="xiao";		//数据库用户名
	String password="xf";	//数据库密码
	String url="jdbc:odbc:myshop";		//数据库连接字符串
	Connection conn = null;
	Statement stmt = null;
	ResultSet rs = null;
	public DbConnect() {
		try {
			//注册驱动程序
			DriverManager.registerDriver(new sun.jdbc.odbc.JdbcOdbcDriver());
			//获得数据库连接
			conn = DriverManager.getConnection (url, user, password); 
			//由于只处理一个事件，设置为自动提交
			conn.setAutoCommit(true);
			//建立Statement对象
			stmt= conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                ResultSet.CONCUR_READ_ONLY);
		}catch(Exception e) {
			System.err.println("数据库连接错误: " + e.getMessage());
		}
	}
	
	public ResultSet executeQuery(String sql) {
		try {
			rs = stmt.executeQuery(sql);
		}catch(SQLException ex) { 
			System.err.println("执行查询错误 : " + ex.getMessage());
		}
		return rs;
	}
	public int executeUpdate(String sql) {
		int affectRows=-1;
		try {
			affectRows = stmt.executeUpdate(sql);
		}catch(SQLException ex) { 
			System.err.println("执行更新错误 : " + ex.getMessage());
		}
		return affectRows;
	}
	public void close()throws SQLException{
		stmt.close();
		conn.close();
	}
}