sqlbean.java

这是书上的<java毕业设计指南与项目实践>的第6章:基于JSP+JavaBean+Servlet的课程管理系统,供大家参考

package com.course;
import java.io.*; 
import java.sql.*; 

public class sqlBean{/// 

public Connection conn=null; 

public ResultSet rs=null; 
//声明数据库连接字符串
private String DatabaseDriver="sun.jdbc.odbc.JdbcOdbcDriver"; 
//DataSource 数据源名称DSN 
private String DatabaseConnStr="jdbc:odbc:ClassDB,'sa',";

//定义方法 
/*setXxx用于设置属性值;getXxx用于得到属性值*/ 
public void setDatabaseDriver(String Driver){ 
this.DatabaseDriver=Driver; 
} 
public String getDatabaseDriver(){ 
return (this.DatabaseDriver); 
} 

public void setDatabaseConnStr(String ConnStr){ 
this.DatabaseConnStr=ConnStr; 
} 
public String getDatabaseConnStr(){ 
return (this.DatabaseConnStr); 
} 

public sqlBean(){/////构造函数 
try{ 


Class.forName(DatabaseDriver); 
} 
catch(java.lang.ClassNotFoundException e){ 
System.err.println("加载驱动器有错误:"+e.getMessage( )); 
System.out.print("执行插入有错误:"+e.getMessage());//输出到客户端 
} 
} 

//执行插入操作的方法	                 
public int executeInsert(String sql){ 
int num=0;
try{ 
conn = DriverManager.getConnection("jdbc:odbc:ClassDB","sa","");
Statement stmt=conn.createStatement( ); 
num=stmt.executeUpdate(sql); 
} 
catch(SQLException ex){ 
System.err.println("执行插入有错误:"+ex.getMessage() ); 
System.out.print("执行插入有错误:"+ex.getMessage());//输出到客户端 
}

CloseDataBase();
return num;
} 
//执行查询操作的方法
 
public ResultSet executeQuery(String sql){ 
rs=null; 
try{ 
conn = DriverManager.getConnection("jdbc:odbc:ClassDB","sa","");
Statement stmt=conn.createStatement( ); 
rs=stmt.executeQuery(sql);
} 
catch(SQLException ex){ 
System.err.println("执行查询有错误:"+ex.getMessage() ); 
System.out.print("执行查询有错误:"+ex.getMessage()); //输出到客户端 
} 

return rs; 
} 
//执行删除操作的方法
public int executeDelete(String sql){ 
int num=0;
try{ 

conn = DriverManager.getConnection("jdbc:odbc:ClassDB","sa","");
Statement stmt=conn.createStatement( ); 
num=stmt.executeUpdate(sql); 
} 
catch(SQLException ex){ 
System.err.println("执行删除有错误:"+ex.getMessage() ); 
System.out.print("执行删除有错误:"+ex.getMessage()); //输出到客户端 
} 
CloseDataBase();
return num;
} 
//关闭数据库连接
public void CloseDataBase(){ 
try{ 
conn.close(); 
} 
catch(Exception end){ 
System.err.println("执行关闭Connection对象有错误："+end.getMessage( ) ); 
System.out.print("执行执行关闭Connection对象有错误：有错误:"+end.getMessage()); //输出到客户端 
} 
} 
}