There is no magic bullets

ORM mapping sounds easy and neat way of managing DB persistency in java. However, in reality it’s not dance with roses. Primarily problem comes from the fact that ORM attempts to hide details, which in reality are crusical for performant and scalable application. People are still writing straight JDBC Code? The Vietnam of Computer Science

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Back in business

After running every day for five years Antec 450P power supply gave up, and died completely. Appearently earlier it had been slowly starting to fail (causing occasional random system restarts). Thus power died far before manufacturer claimed MTFB (80 000h), but slightly after warranty time (5 vs. 3 years). Now, it’s replaced by Corsair VX550W,…

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Cache locality in java

Not new, but still quite interesting to read: Caching and the Java Virtual Machine References: Thread scheduling implications in Java Use stack variables whenever possible Java bytecode: Understanding bytecode makes you a better programmer The Final Word On the final Keyword Premature Optimization Java theory and practice: Managing volatility How fast is Java Volatile? or…

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Mobiililaajakaista

Mobiililaajakaista, 3G, mokkula, tuo onnen ja elämän autuus. Lupaukset operaattoreilla ovat suuria ja katteettomia. Elisa/Saunalahti: Mainostavat ”kattavinta” 3G verkkoa. No tämä katteeton väittämä perustuu siihen, että Elisa kävi lätkäisemässä antennin yhteen pohjoisen hiihtokeskukseen, ja väittää sen perusteella olevansa kattavin. Todellisuudessa Elisalla on vain 2100mhz antenneja lätkäistynä suurien kaupunkin keskukseein eli todellinen nopeus on lähes aina…

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E-du-ca-ti-on

Khan Academy The Khan Academy is a not-for-profit organization with the mission of providing a high quality education to anyone, anywhere.

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Mysteries of Nimbus

About defaults in Nimbus: Nimbus Defaults (originates from: Nimbus UIManager UIDefaults) Misc Textarea background issue Update: 10.7.2010 Skinning a Slider with Nimbus

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Beware of Antipatterns

Instead of having ”this proper way”, anti patterns tend to be even more useful by pointing out issues which are problematic. Java Anti-Patterns

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Converting String to UTF8?

Lets see what happens when trying to convert random string into UTF8 using different methods. [code lang=”java”] package org.kari.test.string; import java.io.IOException; import java.io.OutputStreamWriter; import java.nio.charset.Charset; import org.apache.log4j.Logger; import org.kari.log.LogUtil; import org.kari.util.DirectByteArrayOutputStream; /** * Test UTF8 conversion * * @author kari */ public class UTF8Test { public static final Logger LOG = LogUtil.getLogger(”utf8”); private static final…

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Interactive javascript shell

Naive, but functional interactive javascript shell with Java 6. [code lang=”java”] package org.kari.test.script; import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.io.PrintStream; import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; import javax.script.ScriptException; import org.apache.log4j.Logger; import org.kari.log.LogUtil; /** * Test interactive javascript shell * * @author kari */ public class ScriptShell { public static final Logger LOG = LogUtil.getLogger(”script.shell”); private final…

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Git Book

Quite usefull reference: Pro Git Update: 7.10.2010 What you need to know about your version control system

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