How to backup ElasticSearch with rsync

Although there is a gateway feature implemented in ElasticSearch which basically recovers your index on start if it is corrupted or similar it is wise to create backups if there are bugs in Lucene or ElasticSearch (assuming you have set the fs gateway). The backup script looks as follows and uses the possibility to enable … Continue reading »

ElasticSearch vs. Solr #lucene

GraphHopper – A Java routing engine karussell ads I prepared a small presentation of ‘Why one should use ElasticSearch over Solr’ ** There is also a German article available in the iX magazine which introduces you to ElasticSearch and takes several aspects to compare Apache Solr and ElasticSearch. ** This slide is based on my … Continue reading »

Longest Common Substring Algorithm in Java

For jetwick I needed yet another string algorithm and stumbled over this cool and common problem: trying to find the longest substring of two strings. Be sure that you understand the difference to the LC sequence problem. For example if we have two strings: Please, peter go swimming! and I’m peter goliswi The algorithm should … Continue reading »

Viewing hprof from android with jvisualvm

Add an additional permission to your app <uses-permission android:name=”android.permission.WRITE_EXTERNAL_STORAGE” /> to your manifest Create hprof protected void onDestroy() { super.onDestroy(); try { Debug.dumpHprofData(“/sdcard/data.hprof”); } catch (Exception e) { Log.e(“xy”, “couldn’t dump hprof”); } } or alternatively create a hprof file with: adb shell ps | grep yourpackage; adb shell kill -10 pid Get the hprof … Continue reading »

3D Rotation in Gimp

Erstelle eine zusätzliche transparente Ebene Selektiere nun die Ebene die 3D rotiert werden soll Gehe zu Filter->Abbilden->Auf Objekt Abbilden Wähle auf Quader abbilden Klicke ‘transparenter Hintergrund’ Gehe zu Tab ‘Quader’. Eine Seite bekommt Ebene aus dem 1. Schritt. Alle anderen bekommen die Ebene aus dem 2. Schritt. Gehe zu Ausrichtung->Rotation und verändere wie gewünscht  

Time Traveling with Twitter

Via jetwick the following tweet got my attention: goodnight twitter— Daniel Johansen (@MeisterDaniel) April 02, 2011 The tweet is dated on 04:26 2011-04-02 but I could link to it approx. 6 hours earlier: Yet another tweet via @jetwick from future: http://ow.ly/4rxXh I predict that we will see the correct date 04:26 2011-04-02 tomorrow— Karussell (@timetabling) … Continue reading »

Twitter API and Me

I have a love hate relationship with Twitter. As a user I see the benefits of Twitter, when looking at it without the spam, duplicates and senseless tweets e.g. through jetwick. But as a developer the Twitter API is very ‘heuristic’ and handwaving in a lot areas and makes it complicated to use. I would … Continue reading »

Da Guttenberg Button!

Da Jetwick ja eine Weile aus technischen Gründen ohne den Duplikaterkennungs-Button auskommen musste, packte ich gestern die Gelegenheit beim Schopfe und erweckte den Button im neuem Lichte. Der Button ist besonders bei eigenen Tweets oder bei Tweet mit vielen Retweets interessant: Das erschütternde Ergebnis: nicht alle Twitteraner haben Reuters zitiert!