使用BeanUtils类简化request和resultset转换

转：http://xdwangiflytek.iteye.com/blog/1358275

 

当提交表单时，如果没有使用Struts等框架的话，你的代码可能是这样

 

User user=new User();
user.setUsername(request.getParameter("username"));
user.setPassword(request.getParameter("password"));
user.setEmail(request.getParameter("email"));

   User user=new User();
   user.setUsername(request.getParameter("username"));
   user.setPassword(request.getParameter("password"));
   user.setEmail(request.getParameter("email"));

 如果表单项比较多，每次都要这样写是不是很烦？

 

OK，使用commons-beanutils吧。你只需要这样写

 

try {
    Map params=request.getParameterMap();
    BeanUtils.populate(user , params);
   } catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }

try {
    Map params=request.getParameterMap();
    BeanUtils.populate(user , params);
   } catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }

 

那么处理ResultSet时，如果没有Hibernate等框架，你的代码可能是这样

 

if (rs.next()) {
    User user = new User();
    user.setId(rs.getLong("id"));
    user.setUsercode(rs.getString("usercode"));
    user.setSex(rs.getString("sex"));
    user.setPassword(rs.getString("password"));
    user.setPhone(rs.getString("phone"));
    user.setEmail(rs.getString("email"));
   users.add(user);
}

if (rs.next()) {
    User user = new User();
    user.setId(rs.getLong("id"));
    user.setUsercode(rs.getString("usercode"));
    user.setSex(rs.getString("sex"));
    user.setPassword(rs.getString("password"));
    user.setPhone(rs.getString("phone"));
    user.setEmail(rs.getString("email"));
   users.add(user);
}

 

 是不是也有点烦？OK，这样来写吧

 

ResultSetDynaClass rsdc = new ResultSetDynaClass(rs);
Iterator rows = rsdc.iterator();
ArrayList lists = new ArrayList();
while (rows.hasNext()) {
     User user = new User();
     DynaBean row = (DynaBean) rows.next();
     BeanUtils.copyProperties(user, row);
     lists.add(user)
}

ResultSetDynaClass rsdc = new ResultSetDynaClass(rs);
Iterator rows = rsdc.iterator();
ArrayList lists = new ArrayList();
while (rows.hasNext()) {
     User user = new User();
     DynaBean row = (DynaBean) rows.next();
     BeanUtils.copyProperties(user, row);
     lists.add(user)
}