Some Dec/2013 Notes

1) Some useful JVM params
http://blog.joda.org/2011/08/printcompilation-jvm-flag.html
https://wikis.oracle.com/display/HotSpotInternals/PrintAssembly
http://classparser.blogspot.sg/2010/03/hsdis-i386dll.html

2) UEditor from baidu

http://ueditor.baidu.com

Some other tools from them: http://fex.baidu.com

3) How to check if it’s a postback in jsf 1 & 2:

http://stackoverflow.com/a/5266472/382180

4) A nice timeline javascript library:

http://timeline.knightlab.com/

5) Oracle autonomous_transaction (difference with nested transaction; autonomous proecedure/function/trigger etc):

http://docs.oracle.com/cd/B19306_01/appdev.102/b14261/autonotransaction_pragma.htm

Useful for logging, shadow table etc.

6) Oracle database never block a read on rows even if the rows is/are locked by another session; the resultset will be a fixed snapshot, the rows are fixed (multi-version):

eg: one session opened a cursor to read selection result on a table, during which all rows are deleted and committed in another session, the first session could continue reading the rows using that cursor.

I guess this is one of the reasons Oracle database are sensitive to session/cursor leakage

7) Some developer tools collection, could check this list first whenever one needs a tool:

http://www.hanselman.com/blog/ScottHanselmans2014UltimateDeveloperAndPowerUsersToolListForWindows.aspx

8) Guava v15.0 couldn’t be deployed to Weblogic 12c:

http://stackoverflow.com/a/19627096/382180

9) Java XML Parser error: “Exception in thread “main” java.lang.UnsupportedOperationException: This parser does not support specification “null” version “null”

Solution one, add following jvm setting:

-Djavax.xml.parsers.SAXParserFactory=com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl

Other solutions:

http://www.jroller.com/navanee/entry/unsupportedoperationexception_this_parser_does_not

http://colorcoding.wordpress.com/2010/02/17/unsupportedoperationexception-and-xml-parser-versions/

10) BTrace Project, it enables us change running jvm’s classes:

https://kenai.com/projects/btrace/pages/Home

This is similar to JRebel (?)

11) Workaround for Lov bug: selected invalid Lov value in a <af:table> but validation error message is shown when user moves to the next row of <af:table>.

Workaround is: set ExceptionMode of the data control to “immediate” in DataBinding.cpx file.

http://andrejusb.blogspot.sg/2013/12/workaround-for-infamous-bug-13626875.html

12) Git revert local changes:

http://stackoverflow.com/questions/52704/how-do-you-discard-unstaged-changes-in-git

Quick workaround is:


git stash save --keep-index

git stash drop

13) af:tree af:treeTable get node depth:
https://community.oracle.com/thread/2154226


<af:outputText value="#{bindings.Employees.treeModel.depth}"/>

14) af:fileDownloadActionListener or af:exportCollectionActionListener not working (the bean method is not called)
https://community.oracle.com/message/10902026
I think I encounter same problem of this post, workaround is disable ppr in adf-config.xml
but one need to revisit existing functions if it’s relying on the ppr feature.

Env: jdev11.1.2.4