import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

/**
 * @author Kroda
 *
 */
public class DBHelper {
    private Connection conn;
    public Connection getConn()
    {        
        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
            conn=DriverManager.getConnection("jdbc:sqlserver://localhost;user=sa;password=;databaseName=master");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            conn=null;
        } 
        return conn;

    }
    
    public boolean ExecuSQL(String sql,PreparedStatement pstmt)
    {
        
        try {
            conn=getConn();            
            pstmt=conn.prepareStatement(sql);
            int i=pstmt.executeUpdate();
            if(i<1)return false;
            
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return false;
        }finally
        {
            if(conn!=null)
            {
                try {
                    conn.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }                
            }
        }
        return true;        
    }
}

mport java.sql.PreparedStatement;
import VO.UserVo;
public class UserDAO {
    private PreparedStatement pstmt;
    public boolean InsertUser(UserVo user)
    {
        String strSQL="insert into test values(?,?,?)";
        pstmt =new PreparedStatement();//会出错，其实我真的很想这么写，不好意思我从C#转过来的
        pstmt.setString(1, user.getUsername());
        pstmt.setString(2, user.getUsername());
        pstmt.setString(3, user.getUsername());
        new DBHelper().ExecuSQL(strSQL, pstmt);
        
    }
    
}