The J2EE Struggle

bypassing Same Origin Policy in Chrome to allow debugging GWT

2010-09-03T01:56:00.000-07:00

Found myself creating a GWT application that should consume an existing web-service. The Same Origin Policy stopped the xmlHttpRequest with exception in chrome. When starting chrome with the command line argument --disable-web-security everything worked all fine. For some reason chrome 7.0.503.0.dev did not accept any command line switches, although the canary build 7.0.513.0.canary did.- keep on

Google Appengine and commons fileupload

2010-06-17T23:54:00.000-07:00

implemented a GWT form (multipart/form-data) uploading a file to the server. The server implementation in Appengine is a servlet using commons fileupload to upload the file. The file should be less than 100kb, first attempted this code// item is FileItemStream having (! item.isFormField)InputStream is = item.openStream();byte[] data = new byte[100*1024];int len = is.read(data);Which resulted in

GWT Locale, com.google.gwt.i18n.client.Constants

2010-05-21T00:07:00.000-07:00

Supprisingly when I tried my "old-style-I18N-way", I found that Resourcebundle definitely would not work in the GWT application. A little bit of googling left me with the choice of using the GWT I18N framework or googling more. The choice was the GWT I18N framework, and I tried using the Constants interface as described:Internationalization - ConstantsThe application would not load my 'no' locale

Seems to be longer and longer between posts....

2010-05-20T14:19:00.001-07:00

Well, it could be because my responsibilities at work has changed and I am now more of an architect of non-J2EE environments than I am a J2EE developer at work. Well, the need for developing applications obviously are bigger than the need for spare time so I have started a project on Google app engine, in java obviously. Mostly to learn more of the platform, but it might be a handy little

JDBC fetch size matters!

2009-01-20T11:13:00.000-08:00

wrote a little "old-style" plain JDBC application to report on some data now. The main query returned ~40.000 rows and the application took forever to display the data. The strange thing was that in TOAD the result set popped up immediately.So, I set the fetchSize to 1000 in the statement and the application speeded up alot.s = connection.createStatement();s.setFetchSize(1000);Has to read up on

Spam attack

2008-11-26T23:34:00.000-08:00

hi,had to go for comment moderation as the amount of spam comments are increasing. Tried the word verification option, but that does not seem to help.- keep on struggling

Oracle: count occurrences of string or character in string

2008-03-18T05:52:00.000-07:00

currently writing a combined isnumeric/to_number function and in the middle of it I needed a function to count occurrencec of a string in another string. No magic here, simply plain forward arithmetrics.If the second parameter is not provided the function will count the number of characters in the string. If the second parameter is provided, the function will count the occurrences of the search

Using inline views to avoid the ORA-01468 and outer join in all dates

2008-03-11T02:37:00.000-07:00

In my previous post I introduced the concept of inline views and said I somethimes used them go get around Oracles restrictions on outer joins. We also showed how the dual table could be used to retreive multiple rows without using the union operator. We will take this a bit further this time into something useful that I sometimes face when making select statements. The problem in this post

Oracle inline views and retreiving multiple rows from dual

2008-03-10T05:48:00.000-07:00

My oracle blogs are getting read quite a lot these days, thought I'd follow up with some more Oracle - struggles in my next few posts. We'll start of with a nice oracle construct called 'inline views'. I tend to like views in parts to make my sql statements more readable, in part to centralize and make reuse of difficult constructs possible.Inline views is something I tend to use when the sql

Querying hiearchies in sql, AKA Oracle connect by

2008-03-06T07:08:00.000-08:00

Or how to make a recursive query in Oracle.I faced the challenge of listing all members in a group hiearchy. I had heard mentioned usage of java recursion, temp tables and worse. This had to be possible in a SQL. A quick google gave me the solution, using the connect by operator in Oracle.The table (simplified) looked like thisTable: group_membershipcolumn: group_idcolumn: group_id_memberA sample

Search blog.thej2eestruggle.com

2008-02-26T06:06:00.001-08:00

It's a few posts here now, I use the site myself for solving my everyday struggles. I find my selv using the labelcloud often, missed a search box though. Well, now it's there - search for struggles in the sidebar.- keep on struggling -

newline, \n or even \r in PL/SQL

2008-02-22T03:43:00.000-08:00

In my PL/SQL procedure I had to add a text including newline (\n in java, ascii #10) in a text to be read by a java application. Tried with the codel_text := 'hello\nworld';This did not work, the \n character behaves clearly different in PL/SQL than in Java and only wrote '\n', probably the same as writing a String in Java using \\n. To add the newline character, I had to use chr(10), that

Weird caracters in Oracle AKA setting NLS_LANG parameter

2008-02-21T00:20:00.000-08:00

I am a big fan of the Oracle instant client. Although being a unzip-type-of-installation it needs some tweeking. Living in norway, the norwegian special characters, Æ-Ø-Å tends to look somewhat strange. I am sure there are problems related to other languages as well. the solution is to set the NLS_LANG parameter. I set it in environment variables in windows, Control Panel -> System -> Advanced ->

Circular references is a bad idea, in servlets atleast

2008-02-08T01:16:00.001-08:00

Had a problem with a servlet wrapping an ajax response provider using the CBA framework, a lightweight Ajax framework. Due to a dual mode application both capable of running standalone and in servlet container I had to do some tricks to avoid duplication of code. The standalone application uses the NanoHTTPD with some modifications to simplify CBA development. The Response object of the NanoHTTPD

Building a tiny webserver for standalone apps

2008-01-24T03:29:00.000-08:00

Every now and then when I try out applications they have a built in weserver for misc. purposes. In my latest project I added a tiny webserver for ease during the testphase, however being a standalone application this should also prove valuable in production mode for monitoring and misc. maintenance.The webserver I used was not Springable so my decision now is to pause the BEA Content search

Opensymphony Quartz scheduler, Misfire not firing?

2008-01-22T05:32:00.000-08:00

Had the need for a scheduler in this little project of mine and the urge for using something a little less heavy than BEA WLI triggers seemed believe it or not like a good idea. As the project is wired up using Spring, Open Symphonys Quartz framework looked like just the thing for me. The code is something like this:public void checkAndDispatch(){ // look up DB for work // iterate over

Oracle PL/SQL NO_DATA_FOUND aka. ORA-01403

2008-01-17T00:54:00.000-08:00

I'm no PL/SQL expert, but from time to time I find my self writing procedures due to some requirement in the project I'm currently working on. Now I write this trigger which looks up data in some other table and does some work. All fine, although I thought this would workselect foo into bar from foobar where barfoo = 'foofoo';And the application logic something like thisif foobar is null then --

Removing multiple whitespace from string

2008-01-16T01:35:00.000-08:00

So in this application I needed a String tokenizer in PL/SQL, a quick search and I found one at a blog.However, my application had to handle the ecentuality that there came multiple delimiters at any point in the input string, example:' some_token another_token 'The tokenizer from the blog did not, and was not intended to support this either so I modified it a bit with a bit of code

Javascript hell - gotta "love" IE - not !

2008-01-10T13:48:00.001-08:00

been far to little work on the "privat projects" lately, including my lucene search application. Been struggling a bit though with a PHP/Ajax webapp for in-house use. I have a Synology diskstation, a really nice little appliance. The album sucks a bit though so I started writing my own. In Firefox everything looks nice, see a little sample below of parts of the screen.In IE all my hours of work

The search engine - crawler

2007-08-10T11:54:00.000-07:00

hi,long time since the last post, been on vacation without internet connection...We are probably not speaking of a crawler, more of a traverser actually as we will traverse a well known content repository. Traversing the content repository should be rather easy, but the peculiarities of the virtual content repository makes it kind of tricky though. And in BEA 9.2 which is our target platform here

Search engine for BEA content repository

2007-06-20T11:29:00.000-07:00

For a long time I have been looking for a good search engine for the BEA Virtual Content Repository without actually finding any solution that completely covers all my requirements. So, as of today I decided I will write my own search solution.No elaborate requirement specification, although a few important requirementsit should have a small footprintit should scale for larger repositoriesit

JBoss

2007-06-19T14:11:00.000-07:00

It's been a lot of BEA lately on this blog, just thought I'd write this post to let you know I've worked with other containers as well. Some time ago I was presented with a problem of a stand alone RMI application having extreme response times, up to several minutes.Basically we split the job in three steps,port the entire stand alone RMI "server" to JBosstune the SQL statementstune the

Crawling the web

2007-06-19T14:06:00.000-07:00

hi there,I have this little project in my nursery having urgent needs for web crawling capabilities. Java being an obvious requirement for the task I did a quick google search and found an interesting linkWriting a Web Crawler in the Java Programming Languageanyone having any experiences with this sample code? Any other good suggestions for crawling a website for images contained there?BTW: what

Clustrmap

2007-06-18T14:19:00.000-07:00

quite a long time now between posts, been kind of busy with all other things besides J2EE lately. I'm tracking my stats with google analytics and are quite satisified with that service. Thought i'd give clustrmap a try just to see if the numbers sums up. Will give the readers an opportunity to see the location of visitors as well.I will come with more J2EE struggles here soon.- keep on struggling

Struggling duplicate tags in a sequence

2007-05-01T11:03:00.000-07:00

In my previous post I pointed out two problems I encountered working with an XML document. First problem solved, now the problem of duplicate tags bugged me. This construct is present (somewhat scrambled with respect to contents and tagnames as compared to the original)Please note that the tag companyid is present two