Comlexity In Simplicity

Saturday, June 6, 2015

Ucuz Elektrik

Türkiye'de elektrik tarifeleri 3 zamanlı olarak ücretlendirilmekteler. Bu zaman (tarife) dilimleri aşağıda listelenmiştir.

Gündüz (T1) : 06:00 – 17:00

Puant (T2) : 17:00 – 22:00

Gece (T3) : 22:00 – 06:00

En ucuz elektrik 22.00 - 06.00 arasında satılırken en pahalı elektril 17.00 - 22.00 saatleri arasında satılmakta. Hali hazırda geçerli olan ücret tarifelerine göre "Mesken" tipi abonelerin tarifeleri aşağıda listelenmiştir.

Mesken:

Gündüz: 19,7183

Puant: 35,8753

Gece: 8,0527

Görüldüğü gibi en ucuz zaman dilimi GECE tarifesi olmaktadır. Eğer enerji tüketimimizin tamamını gece tarifesi üzerinden yaparsak harcadığımız aynı enerji miktarı için 3 kat daha az ödüyoruz. Basit bir örnek verir ise ortalama enerji faturamız aylık 60 lira ise ödeyeceğimiz rakam 20 liraya düşüyor. 1 sene içerisinde yapacağımız tasarruf miktarı 40 x 12 = 480 lira. Az bir rakam değil.

Peki enerji tüketimimizin tamamını GECE tarifesi üzerinden yapmak mümkün mü ? Eğer enerjiyi depolayabilir isek evet mümkün. Büyükçe şarj edilebilir bir pilimiz olduğunu düşünün, Tarifenin en ucuz olduğu zaman diliminde kendi kendisini otomatik şarj ediyor ve diğer zaman dilimlerinde ise bu pildeki enerjiyi evimizde kullanıyoruz harcadığımız elektrik miktarını kısmadan ciddi miktarda tasarruf sağladık.

İşte bu şekilde şarj edilebilir bir pil artık var. Elektrikli araçları ile ünlü Amerikan "Tesla" şirketi Power Wall adlı ürün ile karşımızda. Power Wall evinizin duvarına monte ettirebileceğiniz oldukça şık bir ürün. Ancak ürünün fiyatı biraz yüksek 3000$ ve 3500$ fiyat etiketine sahip ki Türkiye standartları için bu ciddi bir rakam. Ancak bu ürünlerin muadilleri daha uygun fiyat etiketi ile çok kısa sürede pazara sürülecektir. Bu durumda daha satın alınabilir bir etiket ile elektrik faturalarımızı ciddi miktarda düşürebilir olacağız.

Monday, May 11, 2015

Latitude Longitude Boundaries on World Map

You might have encountered situations where you wanted to get the latitude and longitude boundaries of an rectangular area on world map, I have put together a simple js application using leaflet js and leaflet.draw plugin to provide the functionality.

You can access the hosted application from here.
You can access the sources from here.

Enjoy and please comment if you encounter any issues.

Figure 1 - Boundary Application

Wednesday, May 6, 2015

How to kill multiple processes from terminal with single line

You might encounter situations where you need to kill group of processes, such as when google-chrome is running. Chrome spawns multiple processes and you might want to shut it down from terminal.

[rozaydin@RO ~]$ ps -e | grep chrome
5017 ?        00:00:01 chrome
5027 ?        00:00:00 chrome-sandbox
5028 ?        00:00:00 chrome
5033 ?        00:00:00 chrome-sandbox
5036 ?        00:00:00 chrome
5055 ?        00:00:00 chrome
5083 ?        00:00:00 chrome
5091 ?        00:00:00 chrome
5107 ?        00:00:00 chrome
5111 ?        00:00:00 chrome
5115 ?        00:00:00 chrome
5123 ?        00:00:00 chrome
5131 ?        00:00:00 chrome
5139 ?        00:00:00 chrome
5142 ?        00:00:00 chrome
5154 ?        00:00:00 chrome
5160 ?        00:00:00 chrome
[rozaydin@RO ~]$

Killing these processes one by one is a tedious task instead you can use below command the kill them with one single line. (Bird massacre with single stone)

ps -e | grep <processname> | awk '{system("kill -9 "$1)}'

[rozaydin@RO ~]$ ps -e | grep chrome | awk '{system("kill -9 "$1)}'
sh: line 0: kill: (5033) - No such process
sh: line 0: kill: (5036) - No such process
sh: line 0: kill: (5055) - No such process
sh: line 0: kill: (5083) - No such process
sh: line 0: kill: (5107) - No such process
sh: line 0: kill: (5111) - No such process
sh: line 0: kill: (5115) - No such process
sh: line 0: kill: (5123) - No such process
sh: line 0: kill: (5131) - No such process
sh: line 0: kill: (5139) - No such process
sh: line 0: kill: (5142) - No such process
sh: line 0: kill: (5154) - No such process
sh: line 0: kill: (5160) - No such process
[rozaydin@RO ~]$
[rozaydin@RO ~]$ ps -e | grep chrome
[rozaydin@RO ~]$

Tuesday, March 24, 2015

How to list rpm dependencies

You can easily list the dependencies the rpm file requires prior installation, this is particularly useful when you are shipping your rpms in a removable media this way you can ensure you have provided all the dependencies.

Open a terminal and type below command,

rpm -qpR name_of_rpm

You will see output like below;

/bin/sh

rpmlib(CompressedFileNames) <= 3.0.4-1

rpmlib(PayloadFilesHavePrefix) <= 4.0-1

...

Wednesday, March 4, 2015

Building Berkeley DB XML for CentOS systems

Go to this link and download Berkeley DB XML. Version used in this guide is "6.0.17". Once the download complete, unzip the file.

[rozaydin@RO Tutorials]$ ls

dbxml-6.0.17.tar.gz

[rozaydin@RO Tutorials]$ tar -xzf dbxml-6.0.17.tar.gz

[rozaydin@RO Tutorials]$ ls

dbxml-6.0.17 dbxml-6.0.17.tar.gz

[rozaydin@RO Tutorials]$ cd dbxml-6.0.17/

[rozaydin@RO dbxml-6.0.17]$ ls

buildall.sh db-6.1.19 dbxml README xerces-c-src xqilla

[rozaydin@RO dbxml-6.0.17]$

DB XML uses XQilla which is an XQuery and XPath 2 library implemented on top of the Xerces-C. DB XML requires Berkeley DB as well. So before using it we need to install each of the following dependencies in the following order;

Build and install Berkeley-DB

Build and install Xerces

Build and install XQuilla

Build and install XML-DB

DB XML compilation failed to compile with java 8 switching to java version "1.7.0_72" compilation completed with no errors. Open a terminal switch to root user and set JAVA variables. (PLEASE note you need to use this same terminal for all commands listed below)

[rozaydin@RO dbxml-6.0.17]$ pwd

/home/rozaydin/Desktop/Tutorials/dbxml-6.0.17

[rozaydin@RO dbxml-6.0.17]$ su -

Password:

Last login: Wed Mar 4 12:19:38 EET 2015 on pts/0

[root@RO ~]# export JAVA_HOME=/usr/java/jdk1.7.0_72

[root@RO ~]# export PATH=$JAVA_HOME/bin:$PATH

[root@RO ~]# cd /home/rozaydin/Desktop/Tutorials/dbxml-6.0.17

[root@RO dbxml-6.0.17]#

Now proceed with building Berkeley DB with configure, make, make install use following commands;

[root@RO dbxml-6.0.17]# ls

buildall.sh db-6.1.19 dbxml README xerces-c-src xqilla

[root@RO dbxml-6.0.17]# cd db-6.1.19/

[root@RO db-6.1.19]# ls

build_android build_vxworks build_windows docs lang README test

build_unix build_wince dist examples LICENSE src util

[root@RO db-6.1.19]# cd build_unix/

[root@RO build_unix]# ../dist/configure --enable-cxx --enable-java

[root@RO build_unix]# make

[root@RO build_unix]# make install

When operation completes this will install Berkeley DB to /usr/local/BerkeleyDB.6.1 directory. Change directory back to where you unzipped XML DB.

[root@RO build_unix]# cd /usr/local/BerkeleyDB.6.1

[root@RO BerkeleyDB.6.1]# ls

bin docs include lib

[root@RO BerkeleyDB.6.1]# cd /home/rozaydin/Desktop/Tutorials/dbxml-6.0.17/

[root@RO dbxml-6.0.17]# pwd

/home/rozaydin/Desktop/Tutorials/dbxml-6.0.17

After this step proceed with building XERCES library.

[root@RO dbxml-6.0.17]# cd xerces-c-src/

[root@RO xerces-c-src]# ls

config CREDITS LICENSE NOTICE samples version.incl

config.h.in doc m4 projects scripts xerces-c.pc.in

configure INSTALL Makefile.am README src xerces-c.spec

configure.ac KEYS Makefile.in reconf tests

[root@RO xerces-c-src]# ./configure

[root@RO xerces-c-src]# make

[root@RO xerces-c-src]# make install

When operation completes this will install XERCES library to /usr/local/bin directory. You should see similar output as below:

test -z "/usr/local/bin" || /bin/mkdir -p "/usr/local/bin"

/bin/sh ../libtool --mode=install /bin/install -c CreateDOMDocument DOMCount DOMPrint EnumVal MemParse PParse PSVIWriter Redirect SAX2Count SAX2Print SAXCount SAXPrint SCMPrint SEnumVal StdInParse XInclude '/usr/local/bin'

libtool: install: /bin/install -c .libs/CreateDOMDocument /usr/local/bin/CreateDOMDocument

libtool: install: /bin/install -c .libs/DOMCount /usr/local/bin/DOMCount

libtool: install: /bin/install -c .libs/DOMPrint /usr/local/bin/DOMPrint

libtool: install: /bin/install -c .libs/EnumVal /usr/local/bin/EnumVal

libtool: install: /bin/install -c .libs/MemParse /usr/local/bin/MemParse

libtool: install: /bin/install -c .libs/PParse /usr/local/bin/PParse

libtool: install: /bin/install -c .libs/PSVIWriter /usr/local/bin/PSVIWriter

libtool: install: /bin/install -c .libs/Redirect /usr/local/bin/Redirect

libtool: install: /bin/install -c .libs/SAX2Count /usr/local/bin/SAX2Count

libtool: install: /bin/install -c .libs/SAX2Print /usr/local/bin/SAX2Print

libtool: install: /bin/install -c .libs/SAXCount /usr/local/bin/SAXCount

libtool: install: /bin/install -c .libs/SAXPrint /usr/local/bin/SAXPrint

libtool: install: /bin/install -c .libs/SCMPrint /usr/local/bin/SCMPrint

libtool: install: /bin/install -c .libs/SEnumVal /usr/local/bin/SEnumVal

libtool: install: /bin/install -c .libs/StdInParse /usr/local/bin/StdInParse

libtool: install: /bin/install -c .libs/XInclude /usr/local/bin/XInclude

After this step proceed building XQuilla library (PLEASE note that you need to provide the xerces-c-src directory using ABSOLUTE path not doing so will fail the compilation)

[root@RO xqilla]# ./configure --with-xerces=/home/rozaydin/Desktop/Tutorials/dbxml-6.0.17/xerces-c-src

[root@RO xqilla]# make

[root@RO xqilla]# make install

When operation completes this will install XQuilla library to /usr/local/lib directory.

The last step involves building XML DB in dbxml directory type below commands:

[root@RO dbxml]# pwd

/home/rozaydin/Desktop/Tutorials/dbxml-6.0.17/dbxml

[root@RO dbxml]# cd build_unix/

[root@RO build_unix]# ../configure --enable-java --with-berkeleydb=/usr/local/BerkeleyDB.6.1 --with-xqilla=/usr/local/lib

[root@RO build_unix]# make

[root@RO build_unix]# make install

When operation completes this will install XML DB to /usr/local/BerkeleyDBXML.6.0/ directory. Verify the installation by typing below commands

[root@RO build_unix]# cd /usr/local/BerkeleyDBXML.6.0/

[root@RO BerkeleyDBXML.6.0]# ls

bin include lib

[root@RO BerkeleyDBXML.6.0]# cd bin

[root@RO bin]# ls

dbxml dbxml_dump dbxml_load dbxml_load_container

[root@RO bin]# dbxml

bash: dbxml: command not found...

[root@RO bin]# ./dbxml

dbxml>

if you see the prompt you are good :)

Sunday, February 8, 2015

sample pom.xml file for javaee rest application

here is the sample pom file i most of the time use to form the basis of my java web application projects. I use slf4j with logback for logging, mockito, junit and jersey test framework for testing and google gson for json conversion.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.demo</groupId>
    <artifactId>demo</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>demo application</name>

    <properties>
        <endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    
    <dependencies>
        
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-web-api</artifactId>
            <version>7.0</version>
            <scope>provided</scope>
        </dependency>
        
        <dependency>
            <groupId>javax.ws.rs</groupId>
            <artifactId>javax.ws.rs-api</artifactId>
            <version>2.0.1</version>
            <scope>provided</scope>
        </dependency>       
        
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>            
            <version>2.3.1</version>
        </dependency> 
        
        <!-- Logging -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.10</version>
        </dependency> 

        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.1.2</version>
        </dependency> 

        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
            <version>1.1.2</version>
        </dependency>
        
        <!-- Test -->
        <!-- https://jersey.java.net/documentation/latest/user-guide.html#d0e15523 -->
        <dependency>
            <groupId>org.glassfish.jersey.test-framework.providers</groupId>
            <artifactId>jersey-test-framework-provider-grizzly2</artifactId>
            <version>2.15</version>
            <scope>test</scope>
        </dependency>
        
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        
        <dependency>            
            <groupId>org.mockito</groupId>
            <artifactId>mockito-all</artifactId>
            <version>1.10.19</version>  
            <scope>test</scope>          
        </dependency>
                        
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <compilerArguments>
                        <endorseddirs>${endorsed.dir}</endorseddirs>
                    </compilerArguments>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.3</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.6</version>
                <executions>
                    <execution>
                        <phase>validate</phase>
                        <goals>
                            <goal>copy</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${endorsed.dir}</outputDirectory>
                            <silent>true</silent>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>javax</groupId>
                                    <artifactId>javaee-endorsed-api</artifactId>
                                    <version>7.0</version>
                                    <type>jar</type>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

Thursday, October 2, 2014

Compiling Open Splice Community Edition on CentOS 6.5

OpenSplice DDS is a high-performance messaging technology, and DDS stands for Data Distribution Service for Real-Time Systems (DDS). To be honest i dont know much actually i know very little at all. It seems to be a middleware (a data bus) that is supposed to make your applications to communicate. I had been involved in an m2m project for automatic meter reading (AMR) in the past. The protocol we used was MQTT based. MQTT was easy to understand easy to use and a pleasure to work with however my experience with dds so far not so pleasant it is not easy to understand not easy to use and not pleasant to work with (my personal opinions these are free to not to agree you are). DDS promises a de-centralized structure compared to one server multiple client approach. Anyway the compile steps for open splice is described step by step at the opensplice web site but there is a catch which is not documented you need to have MPC (Make Project Creator) installed and you need MPC_ROOT environment variable set properly (pointing to directory where you installed MPC). Und you should not be using the MPC from its official web site you need to download modified MPC from PrismTech source repo at git hub. which is A fork of OCI's MakeProjectCreator with some tweaks required to support working with OpenSplice and this piece of information is not documented anywhere (at least not anywhere i can find they should have listed these requirement on their web site again this is my opinion free you are to not to agree) not using the proper MPC causes opensplice compile to fail und lots of headaches. hope someone finds this info valuable and saves some time trying to compile the code.