Java Design Patterns : Behavioral Patterns

Behavioral patterns are concerned with the flow of control through a system. Some ways of organizing control within a system can yield great benefits in both efficiency and maintainability of that system. Behavioral patterns distill the essence of proven practices into readily understood, well known, and easy-to-apply heuristics. Following is the list of all Behavioral patterns: Chain of ResponsibilityCommandInterpreterIteratorMediatorMementoObserverStateStrategyVisitorTemplate Method ...

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Java Design Patterns : Structural Patterns

Structural patterns describe effective ways both to partition and to combine the elements of an application. The ways structural patterns affect applications varies widely: for instance, the Adapter pattern can let two incompatible systems communicate, while Facade lets you present a simplified interface to a user without removing all the options available in the system. Following is the list of structural patterns : AdapterBridgeCompositeDecoratorFacadeFlyweightProxy...

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Four level accordion menu using jQuery

Here is a demo to use jQuery for left hand side menu. Attaching code for the same also. Click here for c...

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Java Design Patterns : Creational Patterns

These patterns support one of the most common tasks in object-oriented programming—the creation of objects in a system. Most OO systems of any complexity require many objects to be instantiated over time, and these patterns support the creation process by helping to provide the following capabilities: Generic instantiation – This allows objects to be created in a system without having to identify a specific class type in code. Simplicity – Some of the patterns make object creation easier, so callers will not have to write large, complex code to...

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Java Design Patterns : Classification

The 23 design patterns covered in the original Design Patterns book had several known applications and were on a middle level of generality, where they could easily cross application areas and encompass several objects. The authors divided these patterns into three types: creational, structural, and behavioral. Creational patterns create objects for you rather than having you instantiate objects directly. This gives your program more flexibility in deciding which objects need to be created for a given case. Structural patterns help...

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Java Design Patterns : Learning Process

We have found that, regardless of the language, learning design patterns is a three-step process. Acceptance Recognition Internalization First, you accept the premise that design patterns are important in your work. Then, you recognize that you need to read about design patterns so you will know when you need them. Finally, you internalize the patterns in sufficient detail that you know which ones might help you solve a given design problem. For some lucky people, design patterns are obvious tools, and these people can grasp...

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Java Design Patterns : Definition

We all talk about the way we do things in our jobs, hobbies, and home life, and we recognize repeating patterns all the time. Sticky buns are like dinner rolls, but I add brown sugar and nut filling to them. Her front garden is like mine, but I grow as till be in my garden. This end table is constructed like that one, but in this one, there are doors instead of drawers. We see the same thing in programming when we tell a colleague how we accomplished a tricky bit of programming so he doesn't have to recreate it from scratch....

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Java Design Patterns : History

It Came From Outer Space... via U.C. Berkeley The inspiration for design patterns in software development is usually attributed to Christopher Alexander, a professor of architecture at U.C. Berkeley. In the late ‘70s, he published several books that introduced the concept of patterns and provided a catalog of patterns for architectural design. Alexander's work sparked interest in the object-oriented (OO) community, and within the next decade, a number of pioneers had developed patterns for software design. Kent Beck and Ward Cunningham were...

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Java Design Patterns : Why ?

Sitting at your desk in front of your workstation, you stare into space, trying to figure out how to write a new program feature. You know intuitively what must be done, what data and what objects come into play, but you have this underlying feeling that there is a more elegant and general way to write this program. In fact, you probably don't write any code until you can build a picture in your mind of what the code does and how the pieces of the...

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