Design Patterns

Design Patterns:

Patterns are solutions for the specific problem in a specific context. 

(OR)

Patterns are solutions to recurring problem in a specific context.

Java Design Patterns:

Java design patterns can be categories into three types.

1. Creational Patterns
2. Behavioral Patterns
3. Structural Patterns

1. Creational Patterns :
                 
• Factory Design Pattern
• Abstract Factory Design Pattern
• Singleton Design Pattern
• Builder Design Pattern
• Prototype Design Pattern
             
2. Behavioral Patterns :
                   
• Chain of Responsibility Design Pattern
• Command Design Pattern
• Interpreter Design Pattern
• Iterator Design Pattern
• Mediator Design Pattern
• Momento Design Pattern
• Observer Design Pattern
• State Design Pattern
• Strategy Design Pattern
• Template Design Pattern
• Visitor Design Pattern
                 
3. Structural Patterns:
                     
• Adapter Design Pattern
• Bridge Design Pattern
• Composite Design Pattern
• Decorator Design Pattern
• Facade Design Pattern
• Flyweight Design Pattern
• Proxy Design Pattern

Core design patterns are also called as GOF (Gang of Four).

You can use GOF Patterns in any domain like J2ee domain, .Net domain, Sap domain etc.

In addition to these GOF Patterns we have some domain specific patterns

When you are developing the application using .Net Patterns Microsoft has provided some patterns which have specific to .Net which are called .Net Patterns.

When we are developing J2ee application Sun has provided some patterns which are specific to J2ee domain etc. like depends on domain.

You can use J2ee domain specific patterns for J2ee application. we can use GOF patterns some times.

J2ee Design Patterns:

J2ee design patterns are divided into the following based on the layer.

1. Presentation Layer Design Patterns or Presentation Tier
2. Business Layer Design Patterns or Business Tier
3. Integration Layer or Integration Tier

1. Presentation Layer Design Patterns (or) Presentation Tier:
            
• Intercepting Filter Design Pattern
• Context Object Design Pattern
• Front Controller Design Pattern
• Application Controller Design Pattern
• View Helper Design Pattern
• Composite View Design Pattern
• Dispatcher View Design Pattern
• Service To Worker Design Pattern
                
2. Business Layer Design Patterns (or) Business Tier:
                
• Business Delegate Design Pattern
• Service Locator Design Pattern
• Session Façade Design Pattern
• Application Service Design Pattern
• Business Object Design Pattern
• Composite Entity Design Pattern
• Transfer Object Design Pattern
• T O Assembler Design Pattern
• Value List Handler Design Pattern
                
3. Integration Layer (or) Integration Tier:
                 
• Data Access Object Design Pattern
• Service Activator Design Pattern
• Domain Store Design Pattern
• Web Service Broker Design Pattern