Subject: Re: DynaBeans, DynaClass, DynaMen From: "Vic C." <[EMAIL PROTECTED]> === Sorry, excited: I see: DynaProperty.getType() ; So based on it I can get the type, and create an "UPDATE TABLE SET X = Y WHERE Z=K" in a base class. Cool. I wonder about original values.... for a reset, etc.
Vic Vic C. wrote: > And... can we give it a datasource argument (instead of con) and use > RowSet instead of ResultSet? > > Vic > > Vic C. wrote: > >> Looks a bit like >> http://www.javaworld.com/javaworld/jw-02-2001/jw-0202-cachedrow.html >> listing #3 of disconnected row set. >> >> Can we get metaData out of it so I can write "auto" updates? >> So a DAO that has a Iterator of DynaBeans. >> Where is DynaBean? Commons? >> >> Vic >> >> Craig R. McClanahan wrote: >> >>> I implemented something a little more memory-efficient than this >>> (doesn't >>> require the entire result set to be in memory) in tonight's nightly >>> build >>> of commons-beanutils, which will therefore be available in the 20020713 >>> nightly build of Struts. You use it something like this: >>> >>> Connection conn = ...; >>> Statement stmt = conn.createStatement(); >>> ResultSet rs = stmt.executeQuery("select * from customers"); >>> Iterator rows = (new ResultSetDynaClass(rs)).iterator(); >>> while (rows.hasNext()) { >>> DynaBean row = (DynaBean) rows.next(); >>> System.out.println("Processing customer " + row.get("account_id")); >>> ... access this row as a DynaBean ... >>> } >>> rs.close(); >>> stmt.close(); >>> >>> I elected to avoid doing the type conversions, so the properties you get >>> back will correspond to their types in the database. >>> >>> Craig >>> >>> >>> On Fri, 12 Jul 2002 [EMAIL PROTECTED] wrote: >>> >>> >>>> Date: Fri, 12 Jul 2002 13:56:38 -0400 >>>> From: [EMAIL PROTECTED] >>>> Reply-To: Struts Users Mailing List <[EMAIL PROTECTED]> >>>> To: [EMAIL PROTECTED] >>>> Subject: RE: DynaBeans, DynaClass, DynaMen >>>> >>>> >>>> >>>> Here is what I am using... Very simple and only returns strings... >>>> >>>> >>>> /** >>>> * Converts a resultset into an ArrayList of DynaBeans >>>> * >>>> * @param resultSet SQL result set to be converted >>>> * @return ArrayList of DynaBeans with all columnnames converted to >>>> * lowercase >>>> * @throws SQLException DOCUMENT ME! >>>> */ >>>> private static ArrayList getDynaBeanArrayList(ResultSet resultSet) >>>> throws SQLException { >>>> >>>> ResultSetMetaData metaData = resultSet.getMetaData(); >>>> int cols = metaData.getColumnCount(); >>>> ArrayList list = new ArrayList(); >>>> DynaProperty[] props = new DynaProperty[cols]; >>>> BasicDynaClass dClass = null; >>>> >>>> for (int i = 1; i <= cols; i++) { >>>> props[i - 1] = new >>>> DynaProperty(metaData.getColumnName(i).toLowerCase()); >>>> } >>>> >>>> try { >>>> dClass = new BasicDynaClass("test", >>>> Class.forName( >>>> >>>> "org.apache.commons.beanutils.BasicDynaBean"), >>>> props); >>>> } catch (Exception e) { >>>> e.printStackTrace(); >>>> } >>>> >>>> while (resultSet.next()) { >>>> >>>> HashMap map = new HashMap(cols, 1); >>>> >>>> for (int i = 1; i <= cols; i++) { >>>> map.put(metaData.getColumnName(i).toLowerCase(), >>>> resultSet.getString(i)); >>>> } >>>> >>>> try { >>>> >>>> DynaBean dbean = dClass.newInstance(); >>>> BeanUtils.populate(dbean, map); >>>> list.add(dbean); >>>> } catch (Exception e) { >>>> e.printStackTrace(); >>>> throw new SQLException("RequestUtils.getArrayList: " >>>> + e.toString()); >>>> } >>>> } // End While >>>> >>>> return (list); >>>> } >>>> >>>> >>>> -----Original Message----- >>>> From: craigmcc [mailto:[EMAIL PROTECTED]] >>>> Sent: Friday, July 12, 2002 12:07 PM >>>> To: struts-user >>>> Subject: Re: DynaBeans, DynaClass, DynaMen >>>> >>>> >>>> >>>> >>>> On Fri, 12 Jul 2002, Thorbjoern Ravn Andersen wrote: >>>> >>>> >>>>> Date: Fri, 12 Jul 2002 07:02:57 +0200 >>>>> From: Thorbjoern Ravn Andersen <[EMAIL PROTECTED]> >>>>> Reply-To: Struts Users Mailing List <[EMAIL PROTECTED]> >>>>> To: Struts Users Mailing List <[EMAIL PROTECTED]> >>>>> Subject: Re: DynaBeans, DynaClass, DynaMen >>>>> >>>>> [EMAIL PROTECTED] skrev: >>>>> >>>>> >>>>>> ...anyone remember DynaMen? >>>>>> >>>>>> Anyhow... I got a Dynabean mechanism working that builds a DynaBean >>>>>> based on the metadata of a SQL result set, populates and array of the >>>>>> little buggers and passes it back to me. For displaying I have a tag >>>>>> library that does not like a call to get('name') as the field name. >>>>>> What is the best way to get around this? >>>>>> >>>>> >>>>> I wrote an AnonyBeans package which uses BCEL to generate beans on the >>>>> fly based on a ResultSet. It is alpha code but works for me, and is >>>>> usable anywhere where you need a real traditional bean, but where you >>>> >>>> >>>> >>>> do >>>> >>>>> not want to serialize it or use its type in Java source. >>>>> >>>>> Is this interesting? >>>>> >>>> >>>> I think it would be interestesting, even though it might not be >>>> universally useful (some containers won't let you introduce new classes >>>> at >>>> runtime). >>>> >>>> I'd also be interested in a mechanism that converted a ResultSet into a >>>> custom DynaClass, with a corresponding DynaBean for each row. This >>>> would >>>> be trivially simple to do -- so simple that it probably makes a >>>> worthwhile >>>> addition to commons-beanutils itself if someone wanted to take this on. >>>> >>>> This wouldn't help you create dynamic input forms, but it would make a >>>> completely flexible bean-like wrapper around a result set so you can >>>> use >>>> Struts tags to display stuff. >>>> >>>> >>>>> -- >>>>> Thorbjørn Ravn Andersen http://biobase.dk/~tra >>>> >>>> >>>> >>>> Craig >>>> >>>> >>>> -- >>>> To unsubscribe, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> For additional commands, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> >>>> >>>> >>>> -- >>>> To unsubscribe, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> For additional commands, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> >>>> >>> >>> >>> -- >>> To unsubscribe, e-mail: >>> <mailto:[EMAIL PROTECTED]> >>> For additional commands, e-mail: >>> <mailto:[EMAIL PROTECTED]> >>> >> > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
