db.java~6~

班级管理系统

package myproject;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.ResultSet;
public class DB {
    private Connection con;
    private Statement st;
    private ResultSet rs;
    public DB() {
        try {
            Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
            con=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost;DatabaseName=mianmu;","sa","");
            st=con.createStatement();
        } catch (ClassNotFoundException ex) {
        } catch (SQLException ex) {
            /** @todo Handle this exception */
        }
    }
    public boolean getblcc(String str) { //增 删 改 函数 return bl  通用
        Connection con = null;
        Statement st = null;
        int i = 0;
        try {
            st = con.createStatement();

            i = st.executeUpdate(str);
            //  System.out.println(i);
            if (i > 0) {
                return true;
            }
        } catch (Exception ex) {
            System.out.println(ex);
        } finally {
            try {
                if (st != null) {
                    st.close();
                }
                if (con != null) {
                    con.close();
                }
            } catch (Exception ex) {
                System.out.println(ex);
            }
        }

        return false;

    }
    public ResultSet Select(String str)
   {
       try {
           rs = st.executeQuery(str);
       } catch (SQLException ex) {
       }
       return rs;
   }
   public int Update(String str)
   {
       int x=0;
       try {
           x = st.executeUpdate(str);
       } catch (SQLException ex) {
       }
       return x;
   }
   public void Close()
   {
       if(rs!=null)
           try {
               rs.close();
           } catch (SQLException ex) {
           }
       if(st!=null)
           try {
               st.close();
           } catch (SQLException ex1) {
           }
       if(con!=null)
           try {
               con.close();
           } catch (SQLException ex2) {
           }
   }
}