Vanganhxinh's Weblog

Centralized unorderlist using CSS

vanganhxinh — Thu, 29 Jan 2009 09:06:29 +0000

I’ve recieved the order to centralize unorderlist using CSS & HTML as the image below:
It looks quite easy at the first time, does it? However, Takaji made a try first and he found out that it’s not as easy as it does. So, we tried again. If someone is looking for it, just take a look. Hope that it’s helpful!

Here’s the source code to be implemented:

1. css.css

@charset “utf-8″;
/* CentrelizedCSS using div by Tham Thi Van Anh 2009 */

.menucontainer {
width:30%; height:20%; margin: auto;
}

.mymenu {
margin: auto;
border-top: 2px solid #999999;
border-left: 2px solid #999999;
border-bottom: 1px solid #CCCCCC;
border-right: 1px solid #CCCCCC;
}

.mymenu: after {margin:0px; padding:0px;}
.mymenu ul {
list-style:none;
text-align:center;
margin-left:auto;
margin-right:auto;
padding:inherit;
padding-left: 10%; padding-right:10%;
}
.mymenu ul li { border: none; }
.mymenu ul li:hover {
border: 1px solid #99CC00;
background-color:#FFFF99;
}

2. .html code: import the code below into the body tag

Item 1

Item 2

Item 3

Item 4

Item 3

Item 4

P.S: If anyone’s got a better solution, please post!!!

Posted in how to

ISE – why!!!

vanganhxinh — Wed, 23 Jul 2008 13:04:48 +0000

Today, I joined to the next subject of this semester: Information System Engineering (ISE) and here is some points after nearly 3 hours class.
First of all, the name ISE, especially E (engineering), I was thinking of what is a very heavy subject (a lot of theory and techniques and so hard to start with it). Luckily, my teacher today made it become quite easier to come up.
Information system engineering mainly refers to the Information System. It means the differences between data and information. This is the first thing you should know when start studying this subject.
In the system, data is normally considered as the raw information, just the dummy thing – hasn’t been processed and also is the system’s input. Then, data will be processed and became information after that. Information has meaning itself, in some ways.

The next thing is the Information System Development cycle (ISD cycle) with some key words: PADIS. This stands for: Planning – Analyzing – Developing – Implementing – Supporting. This is the general cycle and I think it would be covered in some next classes.

Here has one question: what is this subject used for? uhmmm!!! It can be said that ISE is used in how to build a system from the start but mainly covers in methods and techniques. I looked through the text book and they (methods and techniques) are represented in almost chapters. After coming up with those method, techniques, blah blah blah, series of ISE will be posted.
So, releasing a new product (new system), what is the most concerning thing? It’s the quality. What is the good products? How many criterias needed to be marked? They are:

Product must fit with the requirements
Products must be on-time (in releasing)
Products also must be within budget

If your products meet 3 above, it can be considered as a good product. That’s it!!!
However, it’s very hard to reach to both of 3. And many many reports have showed that there are many many projects FALL, FALl, FAll, Fall, fall… WHY???
This was the most interesting part in our class today. All can be put in 2 categories: Human factors and organization factors. I’m not really interesting in business, so I cannot cover the organization factors too much and I need your help (if you could). The Human factors, ^_^ I take a summary after reading slides, listening to my teacher… and all are pointed to the communication problems such as:

Fall because of misunderstanding requirements
Fall because of cannot working by group
Fall because of having many IT’s professional (from developing, planning, managing, …). This is the most funny thing I’ve heard. They’re thinking of PRO themselves that make the project falls.

IT Project Management – first looking

vanganhxinh — Mon, 21 Jul 2008 11:20:55 +0000

This is the first subject that I’ve taken in this semester. Let’s take a look at what is the “Project Management” about!

Project Management = Managing a particular Project. So, here are 3 words needed to make clear:

Managing: can be known as handling or controlling
Particular: can be used as unique(this will be discus later)
Project: is defined as “a temporary endeavor undertaken to accomplish a unique product or service”. This definition shows the meaning of “particular” word above.

As everybody knows, a simple word as project contains many related areas such as: a project of building an accounting program is related not only to calculate numbers but also related to finance, tax, even though rules must follow.

According to definitions and one simple example, these are attributes of a project:

Unique: 1 project is for unique purpose
Temporary: 1 project is only taken in a range of time
Require resources: 1 project is not only inside a bound of an area but also relates to and needs other resources in related areas.
Sponsor/Customer: who is the one will use product/service after project
Uncertainty: as unpredictability (not sure)

Every project is constrains itself by 3 factors: scope, time & cost. These factors build the Triple Constraint. This means each project that is considered as successful needs to achieve 3 goals

Scope: what is the project going to solve
Time: How long will it take to complete
Cost: How many $$ does it take?

Here has a small (not really small) problem occurs when all of those 3 goals is achieved but the client (customer) is not satisfy? So, the last but also the very important factor is quality of the project. A successful project must gain the satisfaction of the customer. Then, the Triple constrains should become the “quadruple constraint”. So the good project management should include more than triple constraint.

Project management is defined as “the application of knowledge, skills, tools and techniques to project activities in order to meet project requirement”.

The framework of project management shows all the factors need to control while managing a project. They are:

Stakeholders: these are people involved or affected by activities of a project. They can be anyone related such as: customers, sponsors, suppliers, staffs and also competitors
Knowledge areas: this describes the available key factors (competences) that project manager must develop. It’s divided into 3 parts. The upper part is the quadruple constraint. The below part contains: HR (human resources) management, communication management, risk management and procurement management. 2 parts will meet at the central part called “project integration management”
Tools & techniques assist project manager.
Project Portfolio (like the group of investments)

So, becoming an IT project management is good or not?

IT PM (Project Management) is one of top-ten most in demand IT skill and is the no.2 of high salary IT job, so fantastic, isn’t it?
Getting certificate: this is needed. You can search for PMP (Project Management Professional) certificate.
PM can apply to other areas, not only in IT.

How to establish the connection to the MySQL database?

vanganhxinh — Sun, 22 Jun 2008 16:54:39 +0000

Welcome back,
A very good news was announced in Jan 16, 2008 from Sun about the agreement to acquire MySQL is still interesting news to developers. And this article is about them, how to establish the connection to the MySQL database
(Sun’s announcement can be read at: http://www.sun.com/aboutsun/pr/2008-01/sunflash.20080116.1.xml)
What you need are:
- Java
- MySQL (of course)

Here’s some notes:
1. The versions are using:
- Java 1.6
- MySQL 5.0 (can be downloaded at: http://dev.mysql.com/downloads/mysql/5.0.html
(Additional: MySQL GUI tools – the GUI without installer, can be downloaded at: http://dev.mysql.com/downloads/gui-tools/5.0.html)

2. Java installation: see previous article at http://vanganhxinh.wordpress.com/2008/02/25/setup-your-java-working-space/

3. MySQL server installation: just follow the installations (next, next…). However, take note the parameters about: user, password, port (default value are: root, pass: you choose, port: 3306)
After installation, there’s a database(schema) named: test. We will use this database later to test the connection using java.

4. Download the MySQL GUI tool without installer, unzip and place into the folder that you place all the java installation. Then it will look like:
C:\appl\mysql\ <– this is the root folder for the mysql GUI tool you unziped.

5. Setting the CLASSPATH variable
- Right-click to the My Computer icon, choose Properties >> Advanced system settings >> Environment Variables.
- At the System variables space, find the variable named: CLASSPATH, if it’s not existed, create a new one. If it’s already there, click to edit the value.
- Back to the mysql folder that you unziped and look for the file that its name looks like: mysql-connector, the extension of this file is: .jar
- Copy the path, with that full file name .jar
- Paste to the value textbox
- Note:
+ If the CLASSPATH is the new one: remember place the .; before the path. This will be: .;C:\appl\mysql\java\lib\mysql-connector-java-5.0.4-bin.jar
+ If edit the existance variable, place the ; before the path. This will be: .;[existance value];C:\appl\mysql\java\lib\mysql-connector-java-5.0.4-bin.jar
- Then Click OK, Ok >> finish

6. Test the connection: Create java class to test the connection
Create 2 java files as the following (place at the same folder):

MySQLConnection.java

import java.sql.Connection;
import java.sql.DriverManager;
import javax.sql.*;public class MySQLConnection {

Connection conn = null;

public MySQLConnection(){}

public void createConnection(){

String driver = “com.mysql.jdbc.Driver”;

String serverName = “localhost:3306″;
String dbName = “test”;
String url = “jdbc:mysql://” + serverName + “/” + dbName;

String username = “root”;
String password = “admin”;

try {
Class.forName(driver);
conn = DriverManager.getConnection( url, username, password);
System.out.println(“Connected to the database”);
}
catch(Exception e){
e.printStackTrace();
}
}

public void closeConnection(){
try {
conn.close();
System.out.println(“Disconnected from database”);
}
catch(Exception e){
e.printStackTrace();
}
}

}

mysqlRun.java

public class mysqlRun {
public static void main(String[] args){
MySQLConnection mysqlConn = new MySQLConnection();
System.out.println(“1″);mysqlConn.createConnection();
System.out.println(“created”);

mysqlConn.closeConnection();
System.out.println(“closed”);
}
}

7. Run the command promt, change to the folder contains 2 java files and complile the MySQLConnection.java before the mysqlRun.java: type
javac MySQLConnection.java
javac mysqlRun.java

Then run the mysqlRun: java mysqlRun

8. Take note while create the connection:
- The driver is: com.mysql.jdbc.Driver <– this’s different with the driver to connect to other database.
- The parameters of getConnection() method are: url, username, password
+ the url has the prototype as: jdbc:mysql://[servername]/[database_name]
+ username: root as default value while installing mysql server
+ password: is your password you choose for the root user while installing mysql server.

These steps above is using as manual. If you are using netbeans and you want to establish the connection to mysql database, just following:
- Expand the Drivers node in the Database Explorer, right click the MySQL(Connector/J driver), choose Connect Using
- replace the default :/ by the: jdbc:mysql:///.
- enter the username (root) and password
- Click Ok to finish.
You can also read the full text at: http://www.netbeans.org/kb/60/ide/mysql.html

9. Take note about MySQL ver 5.0
The database you created sometimes now can be called as schema. Schema and database are using as the same meaning.

Last one:

If you wish to use netbeans to deploy your application, u would make a copy the file: mysql-connector-java-5.0.4-bin.jar to these folders:

- \jre\lib\

- \jre\lib\ext\

Additional code:

File name: MySQLConnection.java

import java.sql.*;

/**
* 23 Jul 2008
* @author Vanganh
*/
public class MySQLConnection {

public MySQLConnection(){}

/**
* create the connection to mySQL db
* @param conn
* @return conn if successfully connect to mySQL db or null if cannot create connection
*/
public static Connection createConnection(){

String serverName = “localhost:3306″;
String dbName = “test”;

String url = “jdbc:mysql://” + serverName + “/” + dbName;
String username = “root”;
String password = “admin”;

try {
Class.forName(“com.mysql.jdbc.Driver”);
Connection conn = DriverManager.getConnection(url, username, password);
System.out.println(“Connected to the database”);
return conn;
}
catch (ClassNotFoundException cnfe)
{
System.out.println(“Fail to load JDBC-ODBC Driver”);
cnfe.printStackTrace();
System.exit(0);
}
catch (SQLException sqle)
{
System.out.println(“Unable to connect to DB”);
System.err.println (“Error message: ” + sqle.getMessage ());
System.err.println (“Error number: ” + sqle.getErrorCode ());
sqle.printStackTrace();
System.exit(0);
}
return null;
}

/**
* shutdown the connection from mySQL db
*/
public static void shutdownConnection(Connection conn){
if(conn == null || conn.toString().isEmpty()) {
System.out.println(“No connection exists to shutdown!!!”);
}
else {
try {
conn.close();
System.out.println(“Disconnected from database”);
}
catch(Exception e){
e.printStackTrace();
}
}
}
}

Database(DB) – DB environment summaries (P2)

vanganhxinh — Fri, 29 Feb 2008 08:10:37 +0000

2. Relational Data Model:

- What is Relational Data Model?

>> It aims to get how data make their relationship by representing the logically structure within tables (relations)

- What are the objectives of Relational Data Model?

>> Allowing high degree of data independence.
>> Giving the substancial (important, real) grounds for dealing with any problems within database.
>> Enable expandsion of set-oriented data.

- Relational Data Structure: see this picture below

A whole table with colums & rows = Relation
An Attribute = A column’s name
A Tuple = A row
A Domain = all the allowable values for 1 or more attributes

Degree = the number of attribute(s)
Cardinality = the number of tuple(s)

Relational Database = collection of Relations with distince relation names.