Reflection in Java is done by using using the java.lang.Class class. This class provides access to all the information within your own applications classes or even the regular java library classes. Let’s say you have a class in a package called com.tt.company.Employee then if you need the metadata of the Employee class you would have to first assign it to the Class as :

Class c = Class.forName(“com.tt.company.Employee”);

Accessing Fields, Methods and Constructors with Reflection

If you are not sure which fields and methods are declared in a class and you don’t have access to the source code then you can easily get this information by simple looping.

For example, if I wanted to access the fields and methods declared in the class Employee then its as simple as the below code.

Field[] fields = c.getFields();
 
Method[] methods = c.getMethods();
for (Field f : fields)
 
System.out.println("Field: " + f.getName());
 
for (Method m : methods)
 
System.out.println("Method:" + m.getName());

You might get some additional methods if you use the getMethods() method. This is because, the getMethods() definition also chooses those methods which are present in any of the super classes present. In this case, if Employee class does not have any super class, but still it is a subclass of Object. Hence methods defined in the Object class would also form a part of the output.

In order to avoid the methods defined in the super class you should use the getDeclaredMethods() instead.

Note: An important point worth mentioning over here is that, the loop would produce only those methods or fields which are marked public. If you don’t have a public field or method it won’t be considered. In order to loop over them, use the getDelcaredFields() or getDeclaredMethods()

Fun Things to do with Relection in Java

You can discover new techniques of programming once you feel the power of Reflection in your hands. The new techniques would include instantiation of objects dynamically, setting of values to fields and invoking methods without calling them explicitly.

Let’s take the case of a Singleton class into consideration for showing the true power of Reflection. For a Java novice, a singleton class is the one which has a private constructor. It isn’t practically true, but let’s assume that it is. Using reflection, this concept of singleton can be broken.

Here is an example of a Singleton class:

public class SingleCandidate {
 
private String name;
 
static int counter = 0;
private SingleCandidate() {
 
counter++;
 
System.out.println("Instance #" + counter);
 
}
public void showName() {
 
System.out.println(name);
 
}
 
}

A Singleton pattern dictates that only one instance of the object must be present at a given point of time in a JVM. So now, let’s take the above Singleton class for a ride with Reflection:

Class singleton = SingleCandidate.class;
 
Constructor privateConstructor =  singleton.getDeclaredConstructors()[0];
 
privateConstructor.setAccessible(true);
//This is scary
 
SingleCandidate obj = (SingleCandidate) privateConstructor.newInstance();
 
SingleCandidate obj2 = (SingleCandidate) privateConstructor.newInstance();

The code is self explanatory and you will realize that in this way you can easily create many instances of the possible candidate for a singleton class in the JVM. How fool proof was that?

Setting Values to Private Fields!

What did you learn in encapsulation? Was it making fields private and public so that private fields could be accessed only by the class in which they are declared?  Reflection can break this too.

//Even more scary
 
Field privateField = singleton.getDeclaredField("name");
 
privateField.setAccessible(true);
privateField.set(obj, "You are not a singleton anymore");
//Access private Constructor
 
System.out.println("Accessing private Constructor: " + privateConstructor.getName());//Get a private field value
 
System.out.println("Accessing private Field: " + privateField.get(obj));
//Invoke a method
 
Method method = singleton.getDeclaredMethod("showName");
 
method.invoke(obj);

Reflection with Generics

If you have tried out the above code in Eclipse you might see some warnings for the Class or Constructor usage. The warning message will be:

Class is a raw type. References to generic type Class<T> should be parameterized

Constructor is a raw type. References to generic type Constructor<T> should be parameterized

To suppress these warnings you will have to use the generic parameter “?” as follows:

Class<?> singleton = SingleCandidate.class;
 
Constructor<?> privateConstructor =  singleton.getDeclaredConstructors()[0];

The questions mark symbol is a wildcard type used in generics. This only applies only if you using Java 5 or higher versions.

Uses of reflection

Reflection is powerful technique when used appropriately. The major usage of reflection comes in when you are building your own framework, compilers or development tools in which you need access to the metadata of the classes created by end users. You surely might have already used the best products of Reflection without even knowing about it.

• JSP gets converted to Servlets using Reflection.
• The Spring framework uses Reflection to administer the references which you declare in your spring-config.xml without you explicitly instantiating any object. The whole concept of Dependency Injection (Inversion of Control) is conveniently implemented with Reflection.
• Reflection also gave birth to the concept of aspect oriented programming.

Reflection is not limited just to this post and nor Reflection is used for the purpose of breaking security. This article was aimed at showing you a direction with which you can explore Reflection more and discover new principles and techniques to build better applications.

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public class LocalInnerClassTest {
	public void defineInnerClass() {
		class MyLocalInnerClass {
			public void doSomething() {				
			}
		}
 
	}
}

Now lets suppose we want to pass a variable in the defineInnerClass() and pass it to the doSomething() for some computation, then according to the specifications on local inner classes methods we must declare the variables as final or else it will result in a compile time error. So the resulting code must be something as follows:

public class LocalInnerClassTest {
	public void defineInnerClass(final int var) {
		class MyLocalInnerClass {
			public void doSomething() {
				System.out.println(var);
			}
		}
	}
}

where var is the variable that must be declared as final to be passed into the doSomething() method of MyLocalInnerClass. Now the mysterious question which I faced was why exactly such a specification has been outlined. Why can’t the inner class simply take the variable as it is and process further.

In order to understand this reason as to why local inner classes can access only final variables, we have to learn how exactly inner classes get translated to the byte code. The moment you come to know this, you can easily see the logic behind making the variables final.

How Are Inner Classes Translated to the Byte Code

Here is the secret. Inner classes as you must have known them from a long time are still mysterious to the JVM. Yes its true. Inner classes have been implemented only to the compiler level. When the classes are compiled which contain inner classes, the byte code which gets generated does not actually implement inner classes as a class within a class. The book on Core Java from makes this statement:

“Inner classes are translated into regular class files with $ (dollar signs) delimiting outer and inner class names and the virtual machine does not have any special knowledge about them”

That means when the above class file from the example is compiled it will generate two class files such as:

1. LocalInnerClassTest.class
2. LocalInnerClassTest$MyLocalInnerClass.class

Unfurling the mystery of final variables

If you apply logic to the above theory of inner class at the byte code level, you have the answer to the mystery of having final variables. For explanation purpose, lets take the same example.

First lets say we make a call to the defineInnerClass() by creating an instance of LocalInnerClassTest. At this point, the instance of MyLocalInnerClass is still not present because the JVM treats it as a separate class at the byte code level. So when the call to defineInnerClass() is made the JVM tries to instantiate an object of MyLocalInnerClass.

But here we run into a problem. The function doSomething() accesses the var variable which is passed down from the outer class method. If you can simply apply logic over here, you can see the problem. How should the JVM pass the variable which has been declared in one class file to the method in another class file?

In order to solve this big problem, the JVM acts smart. It makes a requirement for the developer to make the variable passed from the method of an outer class to be declared as final. How would this solve the problem, you may ask? When you declare the variable var as final the compiler does a trick. The trick being, it quietly places a hidden variable with the name val$var inside the 2nd compiled class file.

The variable val$var is assigned the same value which has been assigned to var since now the compiler knows that the value cannot be changed as it has been declared final. This is very clever, since final variable must always be assigned before compilation.

So there you go. Now, when you run the program from within an application the inner class already has the value which has been assigned to var through its inner hidden variable val$var and thus the mystery gets solved. Therefore you have the concept that local inner class methods can have access to only the final variables of the outer class.

Hey, Local Inner Classes can even access Outer Class member variables directly. How?

Ok, now that we have tackled the above mystery, this is more simpler. The below code gets perfectly compiled

public class LocalInnerClassTest {
     private int var2;
     public void defineInnerClass(final int var){
 	  class MyLocalInnerClass{
 		public void doSomething(){
 			System.out.println(var+var2);
 		}
     	  }
     }
}

You can notice that the local inner class has direct access to even the private variable var2 of its outer class. The reason behind the accessibility of outer member variables directly inside the local inner classes is that, once again the compiler cleverly places one more hidden variable named as this$0 which is a final instance variable of the outer class type. When the inner class object is instantiated the variable this$0 is given a reference to the outer variable with direct access privileges. Hence you can access the outer class member variables directly from within the inner class. Smart isn’t it?

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According to the research done by Chris for enterprise applications, here are some of the important points which the paper elaborates:

1. Make use of the POJO approach, with lightweight frameworks like Hibernate for ORM and Spring AOP for transactional activities.
2. EJB 3 makes it possible to have your business logic sit within your POJO and also make it run outside the container which makes it really usable.
3. Implementing 3 tiers for an application which commonly include
   1. Presentation tier
   2. Business Interfaces for encapsulation + Business tier logic in classes
   3. Persistence tier for handling transactions and concurrency
4. The design should involve,
   1. Modeling your business classes appropriately
   2. Code structuring principles for easier maintenance
      

While the above points are usually very well known amongst the developer community, it helps if you know which decisions should be taken when. Design patterns which have been established over the years play a key role in making such decisions. The white paper explains a few of the design patterns which are particularly mentioned when enterprise applications are into consideration.

I would like to enumerate here, some of the different design patterns which are highlighted in the paper, according to the decisions which fall into 3 main categories.

Decision #1 – Organizing Business Logic

When you have to implement the business logic it is very important to identify the scope and the scale of the application to decide one or the other approaches as stated below,

Transaction Script Pattern:

1. Does not follow the object oriented principles
2. Methods are mapped to application request from the presentation tier, which are called as Transaction Scripts
3. Follows the procedural approach which makes classes less important and methods more important
4. Simple to implement but difficult to understand and maintain the code
5. Mainly used when business application is small

Object Oriented Approach:

1. Maps the objects from real world to the application
2. Easier to understand the application logic
3. Behavior and state are encapsulated inside the mapped objects
4. Lightweight frameworks help to apply this approach to your application.

Table Module Pattern:

1. Involves mapping of database tables to business classes
2. An object of a table includes all rows of the table rather than a single object mapped to one row
3. It suffers from the problem of maintenance.

Decision #2 – Encapsulating of Business Logic

Well designed Business applications always encapsulate logic from the view. This helps in application scalability and security, at the same time providing loose coupling between the different tiers. The patterns which can be adhered to encapsulate business logic are:

Session Facade Pattern:

1. Promotes proper encapsulation of business level logic
2. Handles transactional behavior, security and presentation tier requests
3. Does caching of objects to prevent memory overloading in case of many requests
4. Delegates requests to proper business objects
5. Was earlier implemented by using EJB 2 Session Objects
6. It is heavy on memory and time consuming for testing and development

POJO Facade Pattern:

1. Business logic encapsulated within simple POJO’s
2. Easier to develop and test and can run outside the container
3. Transactions , security and state can be maintained through AOP
4. Spring framework uses this pattern
5. Light on memory
6. Makes use of Dependency Injection for wiring the business classes instead of using JNDI
   

Exposed Domain Model Pattern:

1. Used to avoid extra code for designing the facade
2. Presentation tier can directly access data objects
   
3. Makes use of AOP to access business objects without an intermediate facade layer
4. Drawbacks include the requirement of transactions and data handling by presentation tier
5. Risky since presentation tier can directly manipulate persistent data.

Decision #3 – Database Access

The decision of accessing data is of strategic importance since IO has a major impact on application performance. So apart from making a decision on the databases and normalization it is crucial to have the best approach for accessing it from other tiers in the application. The paper emphasizes that,

Direct JDBC has drawbacks such as:

1. Boiler plate code for handling connection and fetching of data
2. Database specific SQL reduces the portability of the application
3. Maintenance of low level SQL poses problems from schema changes
4. Can be of advantage when vendor specific features have to be accessed

To overcome the disadvantages of JDBC, using a framework like the iBATIS Framework can be advantageous since:

1. Direct SQL queries can be used
   
2. Provides mapping between resultsets and Java Beans through XML descriptor

The Advantages that Persistance Frameworks offer are:

1. Mapping of data to domain objects
2. No need to write SQL code
3. Flexibility offered by configuring XML descriptors for domain level objects and data
   
4. Loading & updating of database as and when required
5. Transactions and concurrency are handled by the framework

Enterprise applications should be modeled and designed properly from the early phases itself. Without following proper approaches from the ones mentioned above can be an invitation for trouble. I hope that these approaches help the developers to come up with good designs for enterprise applications.

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The theme for this article is “Definitive Search“. It means that, instead of beating around the bush for carrying out permutations and combinations of your search queries, why not carry out the search for exactly what we are looking for. By doing this, you would become more sure of getting the most relevant articles to your queries. Notice the ‘more’ here too!

Most of the Definitive Search tricks are obtained by using the Google Advanced Operators. I would like to specify in this article as to where the operators can be utilized ‘more’ efficiently. I was myself thrilled when I tried using these operators which lead me into writing this article.

For this article I am taking a particular case study for search query optimization. So here we go…

Let us take the current situation of the Oracle BEA acquisition. One would be interested in which stories are doing rounds of it on the web. Even if you put the phrase Oracle BEA acquisition in Google you would obviously get a lot of links. Try it:

• Oracle BEA acquisition

But can you tell for sure which of the links are actually speaking specifically about this story? The answer is NO. This is because Google only searches for those articles which have these 3 words viz Oracle or BEA or acquisition.

1. Most common trick – Using Quotes

To circumvent the above analogy lets try one of the most common trick, using “” (quotes) around this phrase, since using them restricts the results to include all the above 3 words and match the articles which have them. Try it:

• “Oracle BEA acquisition”

This time the results look good since all the returned results have the 3 words either in content or their titles. But you still cannot say that the links would have some content surrounding the story. The reason is, if you consider this article itself, the 3 words are mentioned right here above. This means that even this article might get displayed in the results simply because I have used all the 3 words with the exact sequence. But there is no story about the acquisition. Get it?

2. Power of All – Using the operator allintitle

The time has come for using the powerful Google operator allintitle: This operator is used in a situation as above. Now considering the above situation, one would be urged to click on any article which has the 3 words in the title, the reason being articles with such titles are bound to be related exactly to what the title mentions. This is meaning of being definitive. The operator makes it a point to help you search the articles on the web which have the 3 words in their title. Try it:

• allintitle:Oracle BEA acquisition

3. Power of One – Using the operator intitle

Similar to the allintitle you also can use just intitle which searches for articles which have either “Oracle” or “BEA” or “Acquisition” in their content and not all the three in the title. It is good for single word searches which come in title. Let’s say that you just wanted to find some articles which mentioned all the acquisitions made by Oracle but you are not sure of them. The trick would be to use:

• intitle:Oracle acquisition

3. Digging deeper – Using the operator inURL

This one is my favorite trick. I am always looking out for current topics. The web on the other hand has got overloaded with redundant information. The problem lies here. If I search for something I won’t be so sure whether the links in the results are recent or old. Blogs help me the most is using this trick to my advantage. If you are frequent visitor of blogs then you might have noticed that they have the date of publishing right there in the URL. If you notice this blog too then the URL will have the date. Are you thinking what I am thinking?

If you have not understood then lets take the same above example. If you take the 1st example then you would notice that the search results also include old articles. In this case it also lists out BEA’s denial of Oracle merger in 2007. What we are interested is not this, but the news of the acquisition in 2008! So to try out a simple hack to this is to use the inURL operator. Try this:

• “Oracle BEA acquisition” inurl:2008

The usage of inurl:2008 lists out only those links which have been published in 2008, thus furthering making your search definitive.

4. The Perfect Match – Using the operator allinurl

This is the most definitive of all the combinations which I have mentioned above and the most efficient too. But it may not always work because having multiple words all together in an URL is rare. But still if we try this in our example:

• allinurl:Oracle BEA acquisition 2008

This is a huge filtering operator. You can judge it by the results themselves. It gives only a handful of results! Isn’t that brilliant? However, with this operator you cannot judge the quality of the returned results since it all depends on the URL is framed and not on the content! But many a times, I find it exact and helpful. Remember, you don’t have to put slashes (/) in here, just the words which you think might appear in the URL.

5. Look who is spying – Using the operator site

I use this operator sometimes for my amusement. With this operator you can search for keywords only from particular sites. For example:

• Oracle BEA acquisition site:techtracer.com

will search for the articles in this site only! It isn’t helpful much since many sites have inbuilt search feature, including Techtracer. But you can use it for finding comments which you might have made in some site! Sounds like fun!

I remember I had made a comment in DailySeoBlog a few days ago. But hey, I don’t remember which article I had made the comment on. So here is my hack for using the site operator. Just type which name you had entered while commenting. I had used my first name “nitin”. So check this out:

• nitin site:dailyseoblog.com

Amazing isn’t it? Now I know which all articles I had commented upon in the blog. So now I can easily see what people or the author has responded to my comments.

Gimme ‘more’

Using definitive tricks you can now be sure fire way of finding out exactly what you are looking for. But in the end knowing all the tricks will just won’t be helpful if you don’t apply the right tricks at the right time. It comes with habit of constantly searching for ‘more’ information. I will be continuing writing about how to improve your search queries. Many ‘more’ interesting tricks are about to come. So keep yourself subscribed to Techtracer.

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The fact is that, people miss out on these tricks since they are busy finding the keywords! In order to make them aware I will be trying to put up different tricks and their usage as per the requirement so that it becomes easier for you to get the required information in an instant.

This article is specially for the movie lovers since I am one of them. I am not “crazy” about movies but when I am keen to watch a movie I make it sure that the money is well worth spent. This is the place where Google helps me to make most of the decisions quickly. Some of these decisions include finding:

• Release date
• Cast of the movie
• Reviews of the movie
• Theatres where the movie is being aired
• Checking the schedule
• Trailers

So let me reveal the 5 most fantastic Google Movie Search tricks that I frequently use:

1. Movie Reviews

Google provides a meta parameter “movie” for finding details of movies. For example, if you want to search for the details of the movie “The Matrix” then you would have to use,

• movie: The Matrix

This would give you the information on the release year of the movie and also would show you the ratings which the movie has got from well knowns critic web sites. The interesting part of these reviews is that it even shows the number of positive reviews, neutral reviews and negative reviews, sorting by relevance, date and rating.

If you want to stop your friend from pestering you to watch a movie then make sure to check out those negative reviews! If you want to find out the details of a certain character from the view, check out links of the characters in “Frequently mentioned terms”.

2. Discover Movies

If you are left pale from you routine and want to catch up with the new releases then instead of reaching out for the different movie sites just go to,

• http://www.google.com/movies

This will of course give out the American movies. But what if you like to watch movies from your country. Of course, Google must have done something about it! And it does this, in the form of a simple domain change in the URL. For example if you want to find out Indian movies then change the domain in the URL to .co.in Here you go,

• http://www.google.co.in/movies

If this page appears blank to you then it is because of the requirement of the city name you want to see the movie in. If you are from US, just enter the zip code. This is the fantastic feature of the Google Movie search. Enter the city name in the box and watch the results. The results will show you all the theaters of the city with the list of movies which are currently being aired.

Some links worth checking out of this page are the schedules and the consolidated display of movies and theatres.

3. Movie Details

Let’s say that at this instance, you are feeling about watching any romantic movie. The first thing you would do is either ask your friend about a recommendation or walk into a shop to ask which movies are worth watching. You would not need to do this with Google Movie Search in place. All you need is to know what you are looking for. So your keywords in this case would be “romantic movies” . If you want recent ones just sort them by date.

• romantic movies

As with our earlier trick of changing domain, for searching movie by country, you would be short of luck over here. Because the results always would display english movies regardless of the domain of search. But hey, I have a trick for that too. Just a little change in the query,

• romantic hindi movies
• romantic indian movies
• action hindi movies

4. Movie Anatomy

Sometimes it happens so, that you remember a movie but fail to remember the cast of it, even who was the director of it. Google can help you quick fix these thoughts without much waste of time. You don’t have to open any website nor find the specific keywords if you don’t know whom you are searching for. For instance try this,

• director: The Incredibles
• director: Gladiator

The first line highlighted in bold spells out the directly the required answer. Fantastic, isn’t it? Similarly you can find about the entire cast of the film by just doing something similar to this,

• cast: The Incredibles
• cast: Gladiator

Remember that this might not work out in any movie. But for most of the popular movies you would be able to do the above tricks.

5. Trailers

Finally after you have done a hard work of finding the movie details, you would not want to suppress your excitement to go and actually watch the movie. If you cannot wait for long then why not add something more to it. And that is, watching the trailers!

For finding a trailer, you don’t have to visit the official movie website nor search the video sites. Just use the keywords “youtube” and “trailer” with the movie title in between. For example,

• youtube “The Matrix” trailer
• youtube “Gladiator” trailer
• youtube “The Incredibles” trailer

These searches would display two videos from youtube which have been named as trailers. These won’t necessarily be official trailers but they just the right videos which you would like to watch. Even if you don’t get the video playing option in the search results page, click the first link which would open up in youtube.

Bonus Tip: Apart from the fantastic five searches just one more bonus tip to get to the official site of any movie. Just use the keyword site besides the movie name. Examples are:

• “Resident Evil” site
• “Finding Nemo” site
• “The Matrix” site

You might ask, why I have chosen the same movie names in the examples. This is because these are some of my all time favorite movies . Similarly search for your favorite movie information with Google and enjoy it even more. Have fun!

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Over last few months I have been facing this same problem. I browsed the web for answers, even went ahead and bought many books on Website Optimization. All of them more or less targeted the same issue of caching static contents using additional third party tools which improvises upon browser caching thus getting better performance and all that sort of stuff.

Analyzing the Website Performance

There were enough options to start that made me crazy as to which one to go ahead with, I wanted things to be under my control rather than adding complexities. For this I needed information as to what actually is traveling between my web server and web browser. I added loggers in my code to note the timestamps at server, even timed by database queries.

All I wanted to know was what actually was being downloaded by the client. In this situation one tool finally came to my rescue. That was Yahoo YSlow. It helped in finding:

• The contents of the response object which gave a picture of images, scripts, and style sheets that were being downloaded from the server.
• The content size and time taken to download each of them.

Using this tool I came to know that the gzip feature to compress the html pages was not working. I even found some old images hidden in Java script which where never being displayed but where getting unnecessarily downloaded.

Improving the Website Performance

With the above analysis, I managed to fix the performance of my web site. These are two things which I would suggest you to try out in order to improve your web site performance.

1. Minifying JavaScript and CSS files

An important step in improving the load speed of a website is to reduce the download time taken by JavaScript and CSS files. In my case, the attention was focused to minify these files. As a Java developer I always want properly intended code with comments to debug the script. But this actually increases the script size and degrades the website performance, hence one must make sure that CSS & JavaScript files are minified before being deployed in production server. It helps to boost the website performance.

You can check the source code of Google homepage to see they how the JavaScript, HTML file and style sheets are being minified to the best possible way. The loading time for a Google page itself reveals the advantage of using this technique.

2. Combining small images into ONE image

Combine small icons into a single image and use image map to display the section of the image. This feature is being used by many websites for improving performance since a single request is much faster than making 10 individual requests.

Even Microsoft has followed the style of combining multiple images into one, in its search engine home page Live.com. If you see the background image of the page then, you will notice that all small images have been combined to form a single png file.

Fixing these simple issues improved my website performance by 13-15% without actually spending money on increasing bandwidth or taking any extra efforts. However I would like to know if there are any other steps which might help further in improving a site performance.

(Ninad Gawad is a Java EE Developer who blogs at Technology Discussion)

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In this article I will list down the search tricks which I use quite frequently. Be it finding time, meanings or watching the cricket score, searching PDF’s, with Google as the search engine life cannot be more simpler. Here are the 10 most amazing Google Search tricks:

1. Different Types of Files at your will
How many times would you have asked for materials (PDF, PPT, DOC) for a particular topic from a friend? Its almost everyday that we might have the necessity to ask them either for knowledge, preparing a presentation, white-paper or for case studies. Such times it mostly difficult to look out what to exactly search for because most of the times you don’t know about the topic at hand. But this petty keyword unleashes its lethal power at such occasions.

Let’s say I want to implement a case study on SOA which means I have to read a lot of information for SOA. So I just have to find materials which might have already been uploaded on the web in the form of PDF’s, DOC’s or PPT’s. These materials can be easily obtained by doing a search for:

• PDF – service oriented architecture filetype:pdf
• PPT – service oriented architecture filetype:ppt
• DOC – service oriented architecture filetype:doc

2. Scholarly Search
If you want some authenticity of the materials then it would be better to find the materials from educational institutes or universities. For this use the Google scholar search. But suppose you don’t like to switch to Google scholar search you can add the same query with an additional parameter to the normal Google search box,

• service oriented architecture filetype:pdf site:edu

3. Meanings of any word in an instant
Now you do not have to carry a dictionary or install a dictionary software just for the purpose of finding out a meaning of a word. With the wealth of information in Google’s hands, its a piece of cake to find out the meaning of the word. Just use the define: keyword. The meaning would of course be displayed but also a set of other links which might have an alternative definition are also given out with the link to read more about it.

• define:beureaucracy

You would argue here that, a dicitionary gives out more information than this. But what about words that don’t actually fall within the vocabulary. Suppose you want to know what SOA (Service Oriented Architecture) is then you would have no choice. Google Search comes to your rescue in this case,

• Abbreviations – define: SOA
• Jargons – define: Web 2.0
• SMS language – define: LOL

4. Find the time of any location
Many of us might be probably working for client which are based at different locations. And communication has to be carried out frequently carried out in such cases. But before a communication you have to know which time zone the location is falling into otherwise you would be causing a disturbance.

I have seen people installing time zone software for showing the time of the location they would be calling to. But with Google at your hands you don’t have to install any software. It would be just simple to use a query for finding the current time such as,

• time new york

psst….look closely the time on the little clock graphic. It also shows the perfect time!

5. Weather at your fingertips
I had been to GOA for a Christmas vacation in the last week of December. But I made a mistake of not finding out the temperature of GOA before leaving. Had I known that it is hot even in the winter I would not have made the mistake of carrying additional luggage consisting of blankets and jackets.

If you are thinking to visit a place it is useful to know what the temperature of the place is before hand, it can make efficient packing. Google helps you here too. Just use this query without asking anybody or waiting for the news to make a weather report. I wish I had thought of this!

• goa weather

6. Google does live commentary too!
Indians are cricket fanatics. But its amusing to see the organizations here trying to put together tactics to devoid cricket lovers from wasting time to watch the cricket scores instead of doing their work. What I think they fail to understand is that by blocking the live cricket scoring sites they are actually making the employees more curios and provoking them to hunt for proxy networks or listen to the radio or chat with their friends elsewhere.

Jokes apart, you actually don’t need proxy networks to view the live cricket scores if you at least have access to Google. If you want to find the latest info about all the cricket matches then just type,

• cricket

But if you want to find out only about a particular match then use only the names of the two playing nations,

• India Australia

Remember that the scorecard will come only when the play is going on.

7. Calculate with your browser
Every OS has a calculator inbuilt but when the browser is the thing which is constantly open whey bother to open up a calculator. Open Google and straight away type your mathematical expression. You can go all the way from basic arithmetic to trigonometrical expressions. This is simply amazing stuff accomplished by Google.

• 26 * 9000
• sin(90) / cos (90)

8. Compare your currency with others
Now that the dollar is declining, the rest of the world must be busy trying to check the impact of the dollar on their currencies. But first of all one must know how much a particular currency amounts to when cashed in another currency. Google’s inbuilt currency converter just does this.

• 1 USD in INR
• 1 EUR in INR

9. Keep track of the stocks
With the booming stock market it is very important to track the stocks on a day to day basis. Putting a stock ticker in the search box is the most obvious thing you would think of. But it is not always you would remember the stock ticker, you should add the keyword “stocks:” to the company name.

The best part of the obtained result is that it provides a chart which shows the trend in the company’s stock along with important statistics.

• stocks: INFY

Note: Currently the results are restricted to the companies listed in the US stock markets.

10. Wanna find some faces?
This is most interesting trick. You might be needing images for various occasions and searching for images is the most difficult thing because what we expect might not be possibly mapped to a query. But Google has a parameter in place for images in situations we need an image which describes a face.

Suppose I search for the term “happy” then the Google results page displays smileys. But I would like to use images of happy people. Even if I choose the term as “happy face” the results don’t show images which contain people. For this there is a parameter “imgtype” which you can use with the URL. For this put in the URL as follows:

• http://images.google.co.in/images?q=happy&imgtype=face

There are many more variations which can be bought about with the above tricks thus making your search experience not only enriching but also exciting. If I have missed any tricks of common usage, feel free to mention it.

Update 1: Google keeps on experimenting new ways of searching. If you liked the above tricks then don’t miss out my article which mentions how to use the new search experiments introduced by Google. Believe me, they are brilliant!

Update 2 : Search for your favorite movie information with Google and enjoy it even more. Have fun with the 5 Most Fantastic Movie Search Tricks With Google.

Update 3 : Why not carry out the search for exactly what we are looking for? Get excited for trying out 5 Most Exciting Search Tricks with Google Operators

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Image Credit – mountaingoat

If you are bewildered about the fluid and fixed terminology then their concepts are somewhat self-explanatory:

Fixed Layout – The dimensions of blocks in your web design structure are defined by pixel length and not by percentages. The design gets defined by hard coding the pixel lengths. Such designs are displayed uniformly on screens of any resolution or size.

Fluid Layout - The dimensions are on the contrary made in such a manner that they become fluid. Its similar to the concept of water taking the shape of its container. The fluid designs take the shape of the resolution in which the design is being viewed.

After trying my hands on a fixed layout for designing a theme for Techtracer, I felt somewhat relaxed over my earlier efforts of going for a fluid scheme. I am feeling a necessity of sharing it with the readers of this blog, what pros and cons I consider for fluid and fixed layout when it comes to designing your web site from what I have gathered till now.

Fixed Layout vs Fluid Layout

A fixed layout as defined simply means that the length which you give for a certain area will remain the same no matter what. If that is the case, then I am happy because I know that the change in the resolution of size of the screen wont cause problems for my design.

But in case of a fluid layout the area widens on a big screen and if the screen is really huge then your area will be stretched like a rubber band. In short, the mood of the design is dampened. The main problematic area for a fluid layout is the rendering of text.

An Example

Suppose you are viewing the article 5 Rules For A Good Web Design in a 15″ screen of resolution 1024 x 768 then you would notice 7 lines of text in the first paragraph. But this design is built on the fixed layout so even if I view the same article on a wide screen then still it remains the same. But suppose the design was made with the fluid layout then you would have seen,

• 10 to 12 lines on a resolution of 800×600 because of squeezing of content area
• 2 lines probably on a wide screen with larger resolution because of expanding of content area

The large screen with less lines of text make the site look more with large spaces and less content and the reading become harder. Similarly on low resolution, the content area gets squeezed making it look ridiculous. The impression for the design falls down.

For that matter a fixed layout would be perfect because even if the screen comes to a lower resolution the content remains intact. In this case, a scroll bar appears on the browser to view the content placed beyond the browser area. But I would be comfortable with this because the essence of the layout remains as it was designed to be.

For the above reason I believe that fixed layout reigns over fluid layout and I would continue with the same thought. I think this will give a food for thought to the web designers who are in a dilemma of whether to go for a fixed layout or a fluid layout.

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Search engine optimization (SEO) is a term commonly used for the techniques which ensure that your website becomes search engine friendly. This includes making you site adhere to certain rules which makes it easy for the search engine spiders to crawl effortlessly in your site pages and rank them or list them accordingly.

Why is SEO required?

SEO is must required for anyone who wants his/her website to reach to a large audience. For personal blogs, it does not matter much as the content in its sense is somewhat personal and does not cater to a large mass. But the web sites or blogs which cater to a reader’s needs should follow some SEO techniques without which the intention to get the idea across is left unintended. In other words, as you need expressions to make your thoughts move across to the people, you need SEO to make your online information accessible to the worldwide surfers. Thus, SEO is important.

Can you provide any example?

Techtracer is a blog on technology. It includes articles, views, reviews, tutorials, news, resources which cater to a technology. Whatever I write, I make it a point that it should be well served. This means that whenever a person needs help in a particular aspect then my blog should be easily found. For this, I have to adopt SEO. Since SEO concepts are implemented in this site this is easily searchable on search engines.

How to implement SEO?

SEO is a very vast topic and it ranges from designing strategies of your site layout to the words you put in the site. In this particular article I would explain how to make it simple for wordpress users to implement SEO in their wordpress blogs. I will explain you 5 tips by which your site will easily become search able. For the searching aspect I am targeting Google which forms a major part of the of the search queries.

1. Properly use that Title
2. Using Meta tags for targetted searches
3. Making a Sitemap for your blog
4. Using the robots.txt file
5. Highlighting the proper keywords.

These are the 5 basic tips that I would like to elaborate in the forth coming posts which will be very helpful if you are using Wordpress. I am talking about Wordpress because you don’t have to do much since there are plugins which can do the majority of the things for you. So you don’t have to be a technical expert in implementing these basic yet powerful SEO tips. Bookmark this page or subscribe to this blog to get updated automatically for the upcoming posts on SEO for wordpress.

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• About

What is a namespace?

A namespace is an identifier for elements. XML and XSD use the concept of namespaces to define a relationship between the elements and their hierarchy. It means that when their are multiple elements to be defined then it might be possible that some of the elements may tend to have the same name. But having the same name often leads to collision just as the in the case of classes with same names although in different packages but referenced by name alone in a Java program. Hence the concept of namespaces is used in order to distinguish such elements.

Why are namespaces used?

XML and XSD are never meant for human reading. You have to remember that even though XML is a data representation markup language, it would be rare that you will actually be parsing through an XML file to use the data in your application through your own code.

Such parsing is often supplied through the use of API’s like SAX, DOM, JAXB, etc. You would have till now actually used these libraries while dealing with web services since it is field which uses XML, XSD to the maximum. The concept of namespace has no relevance until and unless an XML instance is associated with an XML Schema (XSD). This is because, XSD defines what do the elements in the XML instance actually mean. A standalone XML just makes the data easier to understand to you but to an XML parser it is nothing but a set of elements in some heirarchy.

For example if suppose you have the following XML format:

<employee>
<name>Alan</name>
</employee>

From this an XML parser can list out that the XML instance contains 2 elements in which employee is the root and name is the child of employee. It cannot say anything more than that. For giving more meaning to the elements, XML Schema or XSD should be provided. If you want the parser to know what kind of element employee is then you would have to provide a namespace for the element to be in as follows:

<tt:employee xmlns:tt=”http://techtracer.com/schemas/employee”>
<name>Alan</name>
</tt:employee>

How to interpret namespaces?

In an object oriented language like Java, entities of the real world are mapped to Beans. Beans have properties. And in general every application uses the beans and their properties to provide values which are taken from either a system or an end user. Such values when needed to be transferred in the XML format need some kind of hierarchy to be structured with. For this API’s come to the rescue.

But before we can supply the API with the elements in any adhoc fashion it becomes necessary that we make the API aware of the structure by providing it with the Schema without which the API won’t be able to tell you if anything has gone wrong in the hierarchy or not. Such API are said to be namespace aware API’s.

For Example, if I have an bean inside a package which is to be included into any program then you would include it when required as:

import com.techtracer.*;

//and then make the bean as

MyBean bean = new MyBean();

Now you can refer to the classes within the package successfully.

Comparing the above to namespaces consider the example.

<tt:employee xmlns:tt=”http://techtracer.com/schemas/employee”>
</tt:employee>

Here tt would be an prefix to the elements which has the value of the entire URL and it would correspond to the namespace just as a package in Java and employee would be an element just as the MyBean in Java. If you would not have provided the packages then the Java program would have given out an error. Similarly in a namespace aware XML parser if you don’t specify the namespace of the element then it would not run successfully.

Default Namespaces

java.lang.* is the default package of core java. Comparing with a XSD the default namespace is:

<xsd xmlns=”http://www.w3c.org/2001/01/XMLSchema”>
</xsd>

Here xsd is in the default namespace i.e. the element xsd is an element of the XSD specification. So now we can say that as java.lang is the default package of java similarly the above namespace is the default namespace of XSD. And as Object is the parent of the Java classes the element xsd is the root of the XSD specification

Custom and Target Namespaces

There are libraries in Java, which may / may NOT be required. Library means something which you can refer to when required, else not. So including it unnecessarily as a inherent feature may be disturbing since they are present for specific reasons and not to be imposed as an implicit feature of the language. Consider this example:

<xsd xmlns=”http://www.w3c.org/2001/01/XMLSchema”>
<employee>Alan</employee>
</xsd>

Woops, now here is an error. The element employee is NOT an element of the XSD specification. If you have an XSD validator it will blurt out with a big error message. This is because the XSD specification does not know a thing about your custom element employee. So what do you do? Somehow you should keep your employee in a safe and secure place where it can be recognized as yours. So we can keep it under a custom namespace like “http://techtracer.com/schemas/employee”. So the change required in the above fragment would be as follows:

<xsd xmlns=”http://www.w3c.org/2001/01/XMLSchema” targetnamespace=”http://techtracer.com/schemas/employee”>
<employee>Alan</employee>
</xsd>

So now when the XSD validator comes across the element employee, it just checks if you have told it where it should belong (before starting the ritual of swearing at you!). Now it knows that you have mentioned a thing called targetnamespace. So it knows that your employee actually belongs to a separate specification which is nothing but your custom XML Schema. The new URL which is mentioned in the targetnamespace is your custom namespace itself.

Conclusion

Hope that this article helps to make you understand namespaces quite easily. Feel free to ask a question if you have any doubt about namespaces. Your query will be solved at the earliest.

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