DbVisualizer

DbVisualizer is a database tool for developers and database administrators, helping you with both the development and maintenance of your databases.

It is the perfect solution since the same tool can be used on all major operating systems accessing a wide range of databases.

http://www.minq.se/products/dbvis/download/install.jsp

Firefox Add-ons - Web Developer

Web Developer is the number one add-on for Firefox. It’s an essential for web developers and has a huge array of tools for making web development easier. We use it the most for on-the-fly validation of CSS and HTML as well as inspecting HTML and CSS.

https://addons.mozilla.org/en-US/firefox/addon/60

Wine

To get help about wine:

https://help.ubuntu.com/community/Wine

Creating simple web project using maven

we can use mvn archetype:generate command to generate java web appication using maven. Afterthat,
cd testweb
mvn idea:idea

useful link:
http://books.sonatype.com/maven-book/reference/web.html

JSF (JavaServer Faces)

JavaServer Faces technology simplifies building user interfaces for JavaServer applications.
JavaServer Faces technology includes:

* A set of APIs for representing UI components and managing their state, handling events and input validation, defining page navigation, and supporting internationalization and accessibility.
* A JavaServer Pages (JSP) custom tag library for expressing a JavaServer Faces interface within a JSP page.

Links:
http://java.sun.com/javaee/javaserverfaces/overview.html
http://en.wikipedia.org/wiki/JavaServer_Faces

log4j

This is the way of using log4j in java.

import org.apache.log4j.Logger;

private static Logger log = Logger.getLogger(ExternalAdvertiserAccountAssembler.class);

if (log.isDebugEnabled()) {
log.debug("User [id:"+ currentUser.getId() + "] is authorized to set the Trusted state.");
}

Links:
http://logging.apache.org/log4j/1.2/index.html

Reformat and Optimise code in IDEA

These are the shortcuts to reformat and optimize the code.

Alt+Ctrl+L / Alt+Ctrl+O

hessian binary web service protocol

The Hessian binary web service protocol makes web services usable without requiring a large framework, and without learning yet another alphabet soup of protocols. Because it is a binary protocol, it is well-suited to sending binary data without any need to extend the protocol with attachments.
http://hessian.caucho.com/#Java

In our project i needed to write a test client in C# to use Exposed java API methods.For that I used HessianC#. I added hessiancsharp.dll to the .NET project.
http://www.hessiancsharp.org/

in Java , its like this.
bean id="advertisementService" class="org.springframework.remoting.caucho.HessianProxyFactoryBean"
description Proxy for the user service using HTTP. /description
property name="serviceUrl" value="${admanager.url}remoting/secured/advertisementService"/
property name="serviceInterface" value="com.fastsearch.admomentum.admanager.advertisement.client.ExposedAdvertisementService"/
property name="serializerFactory" ref="hessianSerializer"/
property name="username" value="advertiser@test.com"/
property name="password" value="password"/
/bean

XSLT

XSL stands for EXtensible Stylesheet Language. The World Wide Web Consortium (W3C) started to develop XSL because there was a need for an XML-based style sheet language. XSLT stands for XSL Transformations. We can use XSLT to transform XML documents into other formats, like XHTML.
http://www.w3schools.com/xsl/default.asp
In my project i used it to transform xml document to csv file.
TransformBillingXmlToCsv.xml

xsl:template name="amount"
xsl:text " /xsl:text
xsl:value-of select="currencySymbol"/
xsl:text /xsl:text
xsl:choose
xsl:when test="currencySymbol = 'JPY'"
xsl:value-of select='format-number(value, "#.")'/
/xsl:when
xsl:otherwise
xsl:value-of select='format-number(value, "#.00")'/
/xsl:otherwise
/xsl:choose
xsl:text " /xsl:text
/xsl:template

(tag characters are removed from above sample code)
Here i had to use XSLT format-number() Function and XSLT Element.

http://www.w3schools.com/XSL/func_formatnumber.asp
http://www.w3schools.com/xsl/el_when.asp

Credit card numbers

I had to work with wrong credit numbers but valid numbers for testing purpose. These are two links which was useful for me.

http://www.darkcoding.net/credit-card-numbers/
http://www.auricsystems.com/support-center/sample-credit-card-numbers

Joda Time

Joda-Time provides a quality replacement for the Java date and time classes. The design allows for multiple calendar systems, while still providing a simple API. The 'default' calendar is the ISO8601 standard which is used by XML. The Gregorian, Julian, Buddhist, Coptic, Ethiopic and Islamic systems are also included, and are welcomed further additions. Supporting classes include time zone, duration, format and parsing.

http://joda-time.sourceforge.net/
http://apidoc.org/docset/62
http://apidoc.org/view/35865

Common Era (also known as Christian Era and Current Era; abbreviated CE)is a designation for the period of time beginning with year 1 of the proleptic Gregorian calendar.

http://en.wikipedia.org/wiki/BCE

Speed up the cargo start

To speed up the cargo start, I added these text to setenv.sh ,source it and put apache-tomcat-5.5.25.zip file to relevant path mentioned here.

export MAVEN_OPTS="-Djava.net.preferIPv4Stack=true -Djava.rmi.server.ignoreStubClasses=true -Dtomcat.installer.url=file:///home/chanaka/admo/bin-3.x/apache-tomcat-5.5.25.zip -Dtomcat.alternate.installer.url=file:///home/chanaka/admo/bin-3.x/apache-tomcat-5.5.25.zip $ADMO_OPTS"

Remotely debug your app in Eclipse or Idea

When i needed to debug the app remotely, i needed to put
-Xdebug -Xrunjdwp:transport=dt_socket,address=5005,server=y,suspend=y
in cargo.jvmArguments -Xmx512M -XX:MaxPermSize=128m -Xdebug -Xrunjdwp:transport=dt_socket,address=5005,server=y,suspend=y /cargo.jvmArguments
line in pom.xml. (I'm using InteliJIdea).

useful links:
http://raibledesigns.com/rd/entry/remotely_debug_your_app_in
http://java.sun.com/j2se/1.4.2/docs/guide/jpda/conninv.html
http://lists.nuxeo.com/pipermail/ecm-checkins/2006-December/002644.html

JSTL

I had to format a date to dispaly in the jsp page. For that, i used JSTL. The JavaServer Pages Standard Tag Library (JSTL) encapsulates as simple tags the core functionality common to many Web applications. JSTL has support for common, structural tasks such as iteration and conditionals, tags for manipulating XML documents, internationalization tags, and SQL tags. It also provides a framework for integrating existing custom tags with JSTL tags.

http://java.sun.com/products/jsp/jstl/

I used JSTL Format Library — Tag. This tag has pattern attribute.

http://download-west.oracle.com/otn_hosted_doc/jdeveloper/905/working_with_html_pages/f1_html_xsql_jsp/f1_jspfmtformatdate.html

For that patten, we can give the pattern we need.

http://java.sun.com/j2se/1.4.2/docs/api/java/text/SimpleDateFormat.html

eg:
fmt:formatDate timeZone="${definedTimeZone}" value="${value}" pattern="EEE MMM dd HH:mm:ss z yyyy"

Skip execution of method in specific time of day

/* this test fails if the current time is between 12:00am and 3:00am*/

Calendar now = Calendar.getInstance();
int hour = now.get(Calendar.HOUR_OF_DAY);
String timeCheck = "Current time not between 12:00am and 3:00am";
String timeDescription = "Current time" + ((hour < 3) ? "" : " not") + " between 12:00am and 3:00am";
Assume.assumeThat(timeDescription, equalTo(timeCheck));

Assume is package org.junit;(public class Assume )

ANTLR

Today i worked with some text character parsing. In our project, they have used ANTLR parser. ANTLR, ANother Tool for Language Recognition, is a language tool that provides a framework for constructing recognizers, interpreters, compilers, and translators from grammatical descriptions containing actions in a variety of target languages. ANTLR provides excellent support for tree construction, tree walking, translation, error recovery, and error reporting.

http://www.antlr.org/

We have used both Class LLkParser and Class Parser.Alos one important interface that provides is Interface AST in antlr.collections.

http://www.antlr2.org/javadoc/antlr/LLkParser.html
http://www.antlr2.org/javadoc/antlr/Parser.html#LA(int)
http://www.antlr2.org/javadoc/antlr/collections/AST.html

Payment gateway

A payment gateway is an e-commerce application service provider service that authorizes payments for e-businesses, online retailers, bricks and clicks, or traditional brick and mortar. Paypal and SecurePay are two common payment gateways. Following are the list of gateways.

http://www.paymentgatewaydirectory.com/

In our project we use saferpay payment gateway. In billing-services.xml,
< bean id="billing.paymentService"
class="com.fastsearch.admomentum.billing.service.DefaultPaymentService">
. . .
< !-- this bean is defined in fast-admomentum-paymentgateway.jar -->
< property name="paymentGateway" ref="saferpayPaymentGateway" />
. . .
< /bean>

and in base-configuration.properties, there are lots of configurations.
one of them are,

# The merchant account id with Saferpay
com.fastsearch.admomentum.paymentgateway.saferpay.accountId=XXXXX-XXXXXXXXX

Java Unit testing

This is a simple test class i wrote to test following method.

package com.fastsearch.admomentum.common.time;

import java.io.Serializable;
import java.util.Calendar;
........

public class DateRange implements Serializable {

.....

public boolean isBetween(Calendar date) {
if (getEnd() != null) {
return (date.after(getStart()) && date.before(getEnd()))
|| date.equals(getStart()) || date.equals(getEnd());
} else {
return date.after(getStart()) || date.equals(getStart());
}
}
}

----------------------------------------------

package com.fastsearch.admomentum.common.time;

import junit.framework.TestCase;
import java.util.Calendar;


public class DateRangeUnitTest extends TestCase {

private DateRange dateRange;

public void testIsBetween()
{
assertFalse(isBetweenOutOfBoundTest());
}

private boolean isBetweenOutOfBoundTest()
{
Calendar testDate = Calendar.getInstance();
testDate.clear();
testDate.set(Calendar.YEAR,2007);
testDate.set(Calendar.MONTH,4);
testDate.set(Calendar.DATE,1);

Calendar startDate = Calendar.getInstance();
startDate.clear();
startDate.set(Calendar.YEAR,2007);
startDate.set(Calendar.MONTH,5);
startDate.set(Calendar.DATE,1);

Calendar endDate = Calendar.getInstance();
endDate.clear();
endDate.set(Calendar.YEAR,2007);
endDate.set(Calendar.MONTH,7);
endDate.set(Calendar.DATE,1);

dateRange = new DateRange(startDate, endDate);
return dateRange.isBetween(testDate);
}
}

mvn commands

- clean
mvn clean

- build
mvn install

- skip all the test
mvn install -P test-unit -Dmaven.test.skip=true
mvn install -o -P test-unit -Dmaven.test.skip=true

- run all the tests including selenium tests
mvn -Ptest-all install

- run specific tests (unit test or selenium test)
mvn install -Ptest-all -Dtest=com.fastsearch.admomentum..ClassName
mvn install -P test-all -Dtest=AdvertisementSeleniumTest
mvn install -Dtest=com.fastsearch.admomentum.common.time.DateRangeUnitTest -o -Ptest-all

- run specific tests (unit test or selenium test) with degugging
mvn install -Dtest=com.fastsearch.admomentum.admanager.webapp.selenium.campaign.CampaignSeleniumTest -o -Dmaven.surefire.debug -Ptest-all
mvn install -Dtest=com.fastsearch.admomentum.admanager.reporting.DefaultReportingServiceUnitTest -o -Dmaven.surefire.debug -Ptest-all

Cargo

Cargo is a thin wrapper around existing containers (e.g. J2EE containers). It provides different APIs to easily manipulate containers.

Cargo provides the following APIs:

* A Java API to start/stop/configure Java Containers and deploy modules into them. Also Ant tasks, Maven 1, Maven 2 plugins. Intellij IDEA and Netbeans plugins are offered.
* A Java API to parse/create/merge J2EE Modules

Following are some containers.

* Geronimo 1.x
* JBoss 3.x
* JBoss 4.x
* Jetty 4.x
* Jetty 5.x
* Jetty 6.x
* jo 1.x
* Oc4J 9.x
* Orion 1.x
* Orion 2.x
* Resin 2.x
* Resin 3.x
* Tomcat 3.x
* Tomcat 4.x
* Tomcat 5.x
* WebLogic 8.x

Difference between 'vi' and 'vim' editors

vim is 'vi improved'
More powerful, etc

http://www.dc.turkuamk.fi/docs/soft/vim/vim_diff.html

Job scheduling with Quartz

Quartz is an open source job scheduling framework that provides simple but powerful mechanisms for job scheduling in Java applications. Quartz allows developers to schedule jobs by time interval or by time of day. The two fundamental units of Quartz's scheduling package are jobs and triggers. A job is an executable task that can be scheduled, while a trigger provides a schedule for a job.
Also, any singular job can have many triggers associated with it.

A CronTrigger allows for more specific scheduling than a SimpleTrigger and is still not very complex. Based on cron expressions, CronTriggers allow for calendar-like repeat intervals rather than uniform repeat intervals -- a major improvement over SimpleTriggers.
A "Cron-Expression" is a string comprised of 6 or 7 fields separated by white space. There are 6 mandatory and 1 optional fields.

Field Name
Seconds
Minutes
Hours
Day-of-month
Month
Day-of-Week
Year (Optional)

Expression Meaning
"0 0 12 * * ?" Fire at 12pm (noon) every day

useful links:
http://www-128.ibm.com/developerworks/java/library/j-quartz/

http://quartz.sourceforge.net/javadoc/org/quartz/CronTrigger.html

Daylight saving time

Daylight saving time (DST; also summer time in British English; see Terminology) is the convention of advancing clocks so that afternoons have more daylight and mornings have less. Typically clocks are adjusted forward one hour near the start of spring and are adjusted backward in autumn.

http://en.wikipedia.org/wiki/Daylight_saving_time

In Java, there are two ways to create days. One method is using Calender object.

Calendar c = Calendar.getInstance();
c.clear();
c.set(Calendar.YEAR,2007);
c.set(Calendar.MONTH,9);
c.set(Calendar.DATE,31);
System.out.println(c.getTime());
c.add(Calendar.DATE,1);
System.out.println(c.getTime());

private List calculateIntervals(DateRange dateRange) {
Date date = dateRange.getStart().getTime();
Calendar c = Calendar.getInstance();
c.clear();
c.setTimeZone(dateRange.getStart().getTimeZone());
c.setTime(dateRange.getStart().getTime());
List dates = new ArrayList();
while (c.getTime().compareTo(dateRange.getEnd().getTime()) <= 0) {
dates.add(c.getTime());
Calendar nextDate = (Calendar) c.clone();
nextDate.add(Calendar.DATE,1);
c = nextDate;
}
return dates;
}

This timezone don't work with daylight saving time. The other way is using Date object.

private List calculateIntervals(DateRange dateRange) {
Date date = dateRange.getStart().getTime();
List dates = new ArrayList();
while (date.compareTo(dateRange.getEnd().getTime()) <= 0) {
dates.add(date);
Date nextDate = (Date) date.clone();
nextDate = DateUtils.addDays(nextDate, 1);
date = nextDate;
}
return dates;
}

This Date object time zone cater with daylight-saving time. In date object->cdate->daylightSaving parameter contains the time in milisecond that should add to the date for daylight-saving changes.

Generics

Generics allow you to abstract over types. The most common examples are container types, such as those in the Collection hierarchy.

When you take an element out of a Collection, you must cast it to the type of element that is stored in the collection. Besides being inconvenient, this is unsafe. The compiler does not check that your cast is the same as the collection's type, so the cast can fail at run time.

Generics provides a way for you to communicate the type of a collection to the compiler, so that it can be checked. Once the compiler knows the element type of the collection, the compiler can check that you have used the collection consistently and can insert the correct casts on values being taken out of the collection.

Here is a simple example taken from the existing Collections tutorial:

// Removes 4-letter words from c. Elements must be strings
static void expurgate(Collection c) {
for (Iterator i = c.iterator(); i.hasNext(); )
if (((String) i.next()).length() == 4)
i.remove();
}

Here is the same example modified to use generics:

// Removes the 4-letter words from c
static void expurgate(Collection c) {
for (Iterator i = c.iterator(); i.hasNext(); )
if (i.next().length() == 4)
i.remove();
}

Firefox Add-ons - Fire bug

Firebug integrates with Firefox to put a wealth of development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page...
Firebug 1.2 requires Firefox 3. Firefox 2 users should install the older 1.05 version of Firebug.

https://addons.mozilla.org/en-US/firefox/addon/1843

Linux BASH command line

These are several useful Linux commands.

df ----Display free disk space
gzip ----Compress or decompress named file(s)
history ----Command History
ifconfig ----See the ip address of the machine

This is the url:
http://www.ss64.com/bash/

Selenium IDE

Selenium is a test tool for web applications. Selenium tests run directly in a browser, just like real users do. It runs in Internet Explorer, Mozilla and Firefox on Windows, Linux, and Macintosh, Safari on the Mac.I tested it in Firefox on Linux.The quickest way to learn Selenium is via a Firefox plugin called Selenium IDE.
http://selenium.openqa.org/

We can download it from
http://selenium-ide.openqa.org/download.jsp
I used Version 0.8.7

This is a good link for learning about selenium.
http://blog.taragana.com/index.php/archive/5-minute-guide-to-selenium-ide-and-selenium-rc-test-tools/

Our project(Admomentum) uses Selenium Remote Control rather than Selenium IDE. The Selenium Remote Control allows you to develop test cases and test suites in Java (supports JUnit & NGUnit), PHP, Ruby, Python, Perl and even .NET. It is the most flexible setup but requires some development knowledge to set up and use.

How To Raise a "File Download" Dialog Box

When you serve a document from a Web server, you might want to immediately prompt the user to save the file directly to the user's disk, without opening it in the browser. However, for known MIME (Multipurpose Internet Mail Extensions) types such as Microsoft Word ("application/ms-word"), the default behavior is to open the document in Internet Explorer.You can use the content-disposition header to override this default behavior. Its format is:

Content-disposition: attachment; filename=fname.ext

Content-disposition is an extension to the MIME protocol that instructs a MIME user agent on how it should display an attached file.When Internet Explorer receives the header, It raises a File Download dialog box whose file name box is automatically populated with the file name that is specified in the header.

To apply the header dynamically, create an Active Server Pages (ASP) file that writes the document out to the browser. Use the Response.AddHeader method to add the content-disposition header. For example:

Response.AddHeader "content-disposition","attachment; filename=fname.ext"

in Java
response.addHeader(CONTENT_DISPOSITION, conditionalParse(contentDisposition, invocation));

UTF-8 and shift-jis

UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is able to represent any character in the Unicode standard, yet the initial encoding of byte codes and character assignments for UTF-8 is backwards compatible with ASCII. For these reasons, it is steadily becoming the preferred encoding for e-mail, web pages.

Shift JIS is a character encoding for the Japanese language.

This is a sample example of using encoding in Java.

filename = new StringBuilder();
private static final String DEFAULT_CHARSET = "ISO-8859-1";

try {
filename.append(new String(getText("campaign.download.filename.prefix").getBytes("UTF-8"), DEFAULT_CHARSET))
.append("-")
.append(sdf.format(now))
.append("-")
.append(new String(getCampaign().getName().toLowerCase().replace(" ", "-").getBytes("UTF-8"), DEFAULT_CHARSET))
.append(".csv");
} catch (UnsupportedEncodingException e) {
addActionError(getText("error.advertisementCsv.failedToDownload"));
return INPUT;
}

CSS float Property

The float property allows two div elements to display in same line.The float property sets where an image or a text will appear in another element.Note: If there is too little space on a line for the floating element, it will jump down on the next line, and continue until a line has enough space.

img
{
float: left
}

Remote Access in PostgreSQL databases

When we need to allow to someone to access our PostgreSQL database in our machine, we need to put following code in our pg_hba.conf file.

# Allow a user from host 192.168.12.10 to connect to database
# "postgres" if the user's password is correctly supplied.
#
# TYPE DATABASE USER CIDR-ADDRESS METHOD
host postgres all 192.168.12.10/32 md5

This is a useful site regarding that.

http://developer.postgresql.org/pgdocs/postgres/auth-pg-hba-conf.html

Remote login in Ubuntu

When you need to remote login to a another machine, first you need to change the remote desktop preferences of the machine which you need to connect and then run following command withing your machine.

vncviewer 172.23.69.90
or
vncviewer -fullscreen 172.23.69.90

change the ip address as u need. This is remote login with user interface.

The command for remote login in command pront is:
eg:
ssh silsaj@cmb1u119.cmb1.fast.no

md5sum in Linux

A checksum is a form of redundancy check, a simple way to protect the integrity of data by detecting errors in data that are sent through space (telecommunications) or time (storage). It works by adding up the basic components of a message, typically the assorted bits, and storing the resulting value.
These types of redundancy check are useful in detecting accidental modification such as corruption to stored data or errors in a communication channel. However, they provide no security against a malicious agent as their simple mathematical structure makes them trivial to circumvent. To provide this level of integrity, the use of a cryptographic hash function, such as SHA-256,MD5 is necessary. In cryptography, MD5 (Message-Digest algorithm 5) is a widely used, partially insecure cryptographic hash function with a 128-bit hash value.

md5sum is a computer program that calculates and verifies 128-bit MD5 hashes, as described in RFC 1321. The MD5 hash (or checksum) functions as a compact digital fingerprint of a file. It is extremely unlikely that any two non-identical files existing in the real world will have the same MD5 hash (although as with all such hashing algorithms, in theory there is an unlimited number of files that will have any given MD5 hash).

In Linux, we use following command to check the checksum of a file.
md5sum -b ojdbc14.jar

Regular Expression

This is a simple java application for using regular expressions in Java.

import java.util.regex.*;

public class Regex {

public static void main(String[] args) throws Exception {

Pattern p = Pattern.compile("[,\\s]+");
String[] result = p.split("one,two, three four , five");
for (int i=0; i System.out.println(result[i]);



String textSubject = "aasasa2323";
Pattern brackets = Pattern.compile(".*\\{[h][e][l][l][o]\\}.*");
Matcher fit = brackets.matcher(textSubject);
if (fit.find()) {
System.out.println ("Found");
} else {
System.out.println ("Not found");
}

}

}

Download accelerator for Ubuntu

I'm using Ubuntu 7.10 (Gutsy Gibbon) in the working place. This link was useful for me to find details about it.

http://ubuntuguide.org/wiki/Ubuntu:Gutsy

Axel is a lightweight command line download accelerator for ubuntu. This link provides the procedure to use it.

http://blog.codefront.net/2007/04/29/axel-lightweight-command-line-download-accelerator/


Web developer 1.1.6 is an add-on to Firefox which is a very useful tool for web developers. This is the url:
https://addons.mozilla.org/en-US/firefox/addon/60

Today when I'm giving permissions to files and folders, this article was useful for me.
http://www.freeos.com/articles/4440/