A developer diary

Spring3-Interceptor

admin — Tue, 19 Oct 2010 06:43:07 +0000

Spring 3 – Interceptor to push Attributes in the Model

When you have a lot of Controllers, you’ll come to the need of a general point to push attributes like locale, login-data, user information to your Model.
There are other ways to do this, but i’ll show the Spring way.

First of all you need this entry in your app-config.xml

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>
class="net.mycityscout.www.controller.AddGeneralModelInterceptor"/>
>

AddGeneralModelInterceptor is our custom interceptor class:

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public class AddGeneralModelInterceptor implements HandlerInterceptor {

protected UserDetailImpl getUser() {
Authentication auth = SecurityContextHolder.getContext()
.getAuthentication();
if (auth != null && auth.getPrincipal() instanceof UserDetailImpl) {
return (UserDetailImpl) auth.getPrincipal();
} else {
return null;
}
}

public boolean preHandle(HttpServletRequest request,
HttpServletResponse response, Object handler) throws Exception {
return true;
}

public void afterCompletion(HttpServletRequest request,
HttpServletResponse response, Object handler, Exception ex)
throws Exception {
}

public void postHandle(HttpServletRequest request,
HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {

if (modelAndView != null && getUser() != null) {
modelAndView.addObject("loggedUser", getUser());
}
}

}

That’s it.Now you can put your general attributes in the model on every Request. Spring will execute your interceptor before every Controller-instance.

Flot – a plotting library for jQuery

admin — Sat, 20 Feb 2010 15:25:57 +0000

After some research for a jquery library to present some charts on a website I found this one.It is very configurable and also looks good.
Just set your datapoints and fire Flot up.

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$(function () {
// a null signifies separate line segments
var d3 = [[0, 12], [7, 12], null, [7, 2.5], [12, 2.5]];

$.plot($("#placeholder"), [d3]);
});

Here is a shot of a sample graph:

You can get this great plugin at the Flot-Projectsite

UIActionSheet with dynamic entries

admin — Sat, 20 Feb 2010 14:11:28 +0000

Sometimes you want to present some options to the user that come from a dynamic datasource.In other cases you could use an UITableView, but if you need to show a modal dialog, you can just use UIActionSheet

Here comes the sample code to build it:

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UIActionSheet *viewSetMenu = [[UIActionSheet alloc]
initWithTitle: @"Select a news-page"
delegate:self
cancelButtonTitle:nil
destructiveButtonTitle:nil
otherButtonTitles:nil];

//dynamic build of buttons
//you could loop over an array
[viewSetMenu addButtonWithTitle:@"Google News"];
[viewSetMenu addButtonWithTitle:@"NTV"];
[viewSetMenu addButtonWithTitle:@"BBC"];
[viewSetMenu addButtonWithTitle:@"Cancel"];

//set index for destructive and cancel button (in the set of dynamic buttons)

[viewSetMenu setDestructiveButtonIndex:0];
[viewSetMenu setCancelButtonIndex:3];

//to avoid blocking at bottom from the tabbar,
//we should not add the sheet to a child of the tabbar

[viewSetMenu showInView:self.tabBarController.view];

thanks to Forward Echo for their hint in case you use a TabBar

Wordpress Post-Kalender mit Fullcalendar und jQuery

admin — Mon, 15 Feb 2010 15:54:25 +0000

Das Fullcalendar-Plugin für jQuery ist ein voll konfigurierbarer Kalender mit Schnittstellen für den Abruf von Daten von einem Server.
Ausserdem können Events von einem bstehenden Google-Kalender abgefragt werde.,
Im einem meiner letzten Projekte, habe ich nach einer Alternative zum WP Kalender-Widget gesucht.Dabei bin ich auf dieses Plugin gestossen.

Die Abfrage der Daten erfolgt im JSON-Format.
Hier der PHP-Teil um die Event-Objekte zu erstellen und an den Kalender zu schicken:

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/**
* wp-posts.php to deliver json objects
*/

$posts = get_posts('');
$eventArr = array();

foreach($posts as $post) {

//build event object
$event = new stdClass();
$event->id = $post->ID;
$event->title = $post->post_title;
$event->start = date("Y-m-d",strtotime($post->post_date));
$event->comments = $post->comment_count;
$event->url = get_permalink($post->ID);
$event->allDay = false;

$eventArr[] = $event;
}

echo json_encode($eventArr);

Der Code für die Anzeige im Browser ist sehr kurz und simpel:

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$(document).ready(function() {
$('#fullcalendar').fullCalendar({
editable: true,
aspectRatio: 2,
timeFormat: '',
events: "/wp-posts.php"
});
});

Bei Bedarf kann man natürlich auch weitere Datenquellen einbinden und z.B. eigene Veranstaltungen eintragen.

Das Ergebnis sieht man hier: http://www.es-dev.de/wp-cal.php

Das Modul gibt es hier:

http://arshaw.com/fullcalendar/

X11 forwarding on SSH after su

admin — Tue, 05 Aug 2008 17:46:05 +0000

before you become su,get your MIT-MAGIC-Cookie

xauth list $DISPLAY

you’ll see an output like
myhost.mydomain:21 mit-magic-cookie-1 4d22408a71a55b41ccd1657d377923ae

switch to root (’su’)

add your cookie to the session
xauth add myhost.mydomain:21 mit-magic-cookie-1 4d22408a71a55b41ccd1657d377923ae

that’s it, now you can start your forwarded X11-Application

sometimes you have to set your $DISPLAY variable,so copy the value from ‘echo $DISPLAY’ before su and set export $DISPLAY=”myhost:XY” when you’re root

The find fiasco

admin — Tue, 05 Aug 2008 17:37:44 +0000

If you want to be sure you don’t delete files you wanted to keep (like root-directory)

never use: find /my/directory * -mindepth 1 -exec rm -r {} \; (VERY BAD)

if it doesn’t find any files in your given path it will try to delete the filenames expanded by ‘*’ AFTER your given path

better use: find /my/directory -name ‘*’ -mindepth 1 -exec rm -r {} \;

metaMatic beta-Release

admin — Sun, 29 Jun 2008 15:47:39 +0000

metaMatic ist a small piece of software to help you managing your music metadata and artwork.

because it’s written in pure java you can use it on every OS with an installed runtime > 1.5, on OS X you’ll need Leopard and Java 1.6.

Start:

usually you can double-click on metamatic.jar, if that doesn’t work you have to type ‘java -jar metamatic.jar’ in the dist-directory

Usage:

Just drag’n drop your music directories in upper left area.You’ll see your tracks and their metafields.

You can mark all tracks to see if they’ve all the same album & artist set.If not you’ll see ‘multiple’,just click in the field and edit the value.

To set an artwork for you album just click on one of the images in the bottom-panel,if it’s empty check your artist/album fields.

implemented features:

- recursive loading of album-directories

- read & display common metafields & artwork

- edit common metafields & multiple edit for album/artist

- auto query artwork-provider for selected album

- load multiple artworks on multiple album-entries in one directory

- write all changes to filesystem after editing is done

upcoming features:

- progress & loading bars

- ogg & mp4/aac artwork-support

- gui design and better element descriptions

- selection for used artwork-provider

- dynamic load of artwork providers (reflection or config-file)

used libraries:

- commons-codec

- commons-httpclient

- commons-io

- commons-logging

- jaudiotagger

For feedbacks and feature ideas contact me under es@es-dev.de

Download: download metaMatic

dynamic Hibernate criteria query

admin — Fri, 23 May 2008 19:50:00 +0000

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Criteria criteria = new GenericDAO(entityManager, utx).getHibernateSession().createCriteria(DateEntry.class)
.createAlias("user", "user")
.createAlias("employee", "employee");

if (employee != null) {
criteria.add(Expression.eq(“employee”, employee));
}
if (customer != null) {
criteria.add(Expression.eq(“user”, customer));
}
if (category != null) {
criteria.createAlias(“categories”, “category”).add(
Expression.eq(“category.id”, category.getId()));
}
if (pending != null && closed != null) {
criteria.add(Expression.eq(“pending”, pending));
criteria.add(Expression.eq(“closed”, closed));
}
if (date != null && dateTo != null) {
criteria.add(Expression.between(“time”, date, dateTo));
}

if (orderParam != null) {
String orderParams[] = orderParam.split(“,”);

for (String orderParamEntry : orderParams) {

if (orderAscending) {
criteria.addOrder(Order.asc(orderParamEntry));
} else {
criteria.addOrder(Order.desc(orderParamEntry));
}
}
} else {
if (orderAscending) {
criteria.addOrder(Order.asc(“time”));
} else {
criteria.addOrder(Order.desc(“time”));
}
}

To avoid double-entries, use this code:

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filter.add(Restrictions.eq("user", user));
filter.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
List<DateEntry> results = filter.list();