sqlbean.java

采用基于B/S结构进行开发学生管理信息系统,本系统采用Servlet+Jsp+JavaBean+MySQL 的设计方式

package myBeans;
import java.io.*; 
import java.sql.*; 

public class SQLBean{/// 

public Connection conn=null; 

public ResultSet rs=null; 

private String DatabaseDriver="com.mysql.jdbc.Driver"; 
//DataSource 数据源名称DSN 
private String DatabaseConnUrl="jdbc:mysql://localhost/studb";
private String DatabaseConnName="root";
private String DatabaseConnPW="125125";

//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 setDatabaseConnName(String ConnName){ 
this.DatabaseConnName=ConnName; 
} 
public String getDatabaseConnName(){ 
return (this.DatabaseConnName); 
} 

public SQLBean(){/////构造函数 
try{ 
Class.forName("com.mysql.jdbc.Driver"); 
} 
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 
} 
} 

	                 
public int executeInsert(String sql){ 
int num=0;
try{ 
conn = DriverManager.getConnection(DatabaseConnUrl,DatabaseConnName,DatabaseConnPW);
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;
} 
// display data 
 
public ResultSet executeQuery(String sql){ 
rs=null; 
try{ 
conn = DriverManager.getConnection(DatabaseConnUrl,DatabaseConnName,DatabaseConnPW);
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; 
} 
// delete data 
public int executeDelete(String sql){ 
int num=0;
try{ 
conn = DriverManager.getConnection(DatabaseConnUrl,DatabaseConnName,DatabaseConnPW);
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;
} 
////////////////// 
public void CloseDataBase(){ 
try{ 
conn.close(); 
rs.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 
} 
} 
}