connectiondb.java

新闻发布系统

package mypackage;

import java.io.*; 
import java.sql.*; 

public class ConnectionDB{
  public Connection conn; 
  public ResultSet rs;
  public int num = 0;
  private String driver="sun.jdbc.odbc.JdbcOdbcDriver"; 
  private String url="jdbc:odbc:MyDB";
	
	//加载数据库驱动
	public ConnectionDB(){
		try{ 
			Class.forName(driver); 
		} 
		catch(Exception e){ 
			System.err.println("加载驱动器有错误:"+e.getMessage());
		} 
	} 

	//插入方法                 
	public int executeInsert(String sql){ 
		try{ 
			conn = DriverManager.getConnection(url);
			Statement stmt = conn.createStatement(); 
			num = stmt.executeUpdate(sql); 
		} 
		catch(SQLException e){ 
      System.err.println("执行插入有错误:"+e.getMessage()); 
		}
		finally{
			CloseDataBase();
		}
		return num;
	} 
	
	//查询方法
	public ResultSet executeQuery(String sql){ 
		try{ 
			conn = DriverManager.getConnection(url);
			Statement stmt = conn.createStatement(); 
			rs = stmt.executeQuery(sql);
		} 
		catch(SQLException e){ 
			System.err.println("执行查询有错误:"+e.getMessage()); 
		}
		return rs; 
	} 
  
  //更新方法
  public int executeUpdate(String sql){
    try{
      conn = DriverManager.getConnection(url);
      Statement stmt = conn.createStatement();
      num = stmt.executeUpdate(sql);
    }
    catch(SQLException e){
      System.err.println("执行更新有错误:"+e.getMessage()); 
    }
    finally{
      CloseDataBase();
    }
    return num;
  }
	
	//删除方法
	public int executeDelete(String sql){ 
		try{ 
			conn = DriverManager.getConnection(url);
			Statement stmt = conn.createStatement(); 
			num = stmt.executeUpdate(sql); 
		} 
		catch(SQLException e){ 
			System.err.println("执行删除有错误:"+e.getMessage());  
		} 
		finally{
			CloseDataBase();
		}
		return num;
	} 
 
	//关闭数据库连接
	public void CloseDataBase(){ 
		try{ 
			conn.close(); 
		} 
		catch(Exception e){ 
			System.err.println("执行关闭Connection对象有错误："+e.getMessage());
		}
	} 
}