dbconnection.java

教材管理系统,一个完整的学校教材管理系统,可以作为大学生课程设计使用

package tom.bean;
import java.sql.*;
import java.io.*;
import java.util.*;
public class Dbconnection {
     private Connection con;
     private Statement sql;
     private ResultSet rs;
     private int rowcount;
     private String message;
     public Dbconnection() {
     	con=null;
     	sql=null;
     	rs=null;
     	rowcount=0;
     	message=null;
     	try{Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
             //Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
        }
     catch(ClassNotFoundException e) {}
     }
     //连接数据库
    public void condb(){
     try{//con=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=JCGL","sa","123");
           con=DriverManager.getConnection("jdbc:odbc:jcgl","sa","sa");
           sql=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
    }
    catch(SQLException f1)  {System.err.println("Dbconnection.condb():"+f1.getMessage());}
    }
    //查询数据库
    public ResultSet select(String sqlstring)
    {try{
    	rs=sql.executeQuery(sqlstring);
    	return rs;
    	}
     catch(SQLException f2)  {System.err.println("Dbconnection.select():"+f2.getMessage());}
     return rs;
    }
    //更新数据库
    public void update(String sqlstring)
    {try{
    	sql.executeUpdate(sqlstring);
    	}
     catch(SQLException f3)  {message="error";}
    	
    }
    public String getMessage()
    {
    	return message;
    }
    public int getRowcount()
    {
    	try{rs.last();
    	rowcount=rs.getRow();
    	rs.beforeFirst();
    	}
    	catch(SQLException f6)  {System.err.println("Dbconnection.getRowcount():"+f6.getMessage());}
    	return rowcount; 
    }
   
}