getnum.java

jsp+javabean的一个在线考试系统的设计（包含教学文档）

package tom;


import java.sql.*;

public class Getnum{
	Connection con=null;
	Statement st=null;
	ResultSet rs=null;
	
	public Getnum(){
		try{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		}
		catch(ClassNotFoundException e){
		}

	}
    public int getC_amount(){
		int c_amount=0;
		try{
			con=DriverManager.getConnection("jdbc:odbc:grad","xiaoyan","");
			st=con.createStatement();
			String sql="SELECT * FROM choice";
			rs=st.executeQuery(sql);
			while(rs.next()){
				c_amount++;
			}
			con.close();
		}
		
		catch(SQLException e){
			c_amount=0;
		}
	    return c_amount;
	}
	
	public int getJ_amount(){
   	    int J_amount=0;
   	    try{
			con=DriverManager.getConnection("jdbc:odbc:grad","xiaoyan","");
			st=con.createStatement();
			String sql="SELECT * FROM judge";
			rs=st.executeQuery(sql);
			while(rs.next()){
				J_amount++;
			}
			con.close();
		}
		catch(SQLException e){
			J_amount=0;
		}
	    return J_amount;
   }
}