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Domain Modelling Patterns

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There are two main patterns for organizing business logic: the procedural Transaction script pattern, and the object-oriented Domain model pattern. 1. Transaction script pattern: An important characteristic of this approach is that the classes that implement behavior are separate from those that store state. When using the Transaction script pattern, the scripts are usually located in serviceclasses, which in this example is the OrderService class. A service class has one method for each request/system operation. The method implements the business logic for that request. It accesses the database using data access objects (DAOs), such as the OrderDao. The data objects, which in this example is the Order class, are pure data with little or no behavior. This style of design is highly procedural and relies on few of the capabilities of objectorientedprogramming (OOP) languages. This what you would create if you were writing the application in C or another non-OOP language. Neverthe
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Guice Tutorial

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Below is a short & crisp tutorial on Guice and the functionalities offered by it What is Guice? Guice is framework in Java to inject dependencies to configure Java Objects. The dependency injection pattern leads to code that is more modular & testable. Consider an interface BillingService as below: Consider below implementation of the BillingService Class: It is easy to see the problems with above solutioning as it would make testing the code impossible! Let's model the BillingService implementation by including its dependencies in constructor: It is now possible to send mock Object or FakeCreditCard Object using a custom FakeCreditCardProcessor. But it still has a problem that BillingService's client need to lookup it dependencies , basically you will need to construct dependencies recursively while you need to use a service. This is where Guice comes for rescue! Dependency Injection with Guice To Use Guice for dependency injection in above examp
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Spring Framework Tutorial

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Please go through the below points to have a thorough understanding of basic functionalities offered by the spring framework. 1. Spring IOC container:  IoC is also known as dependency injection (DI). It is a process whereby objects define their dependencies (that is, the other objects they work with) only through constructor arguments, arguments to a factory method, or properties that are set on the object instance after it is constructed or returned from a factory method. The container then injects those dependencies when it creates the bean. This process is fundamentally the inverse (hence the name, Inversion of Control) of the bean itself controlling the instantiation or location of its dependencies by using direct construction of classes or a mechanism such as the Service Locator pattern. 2. In Spring, the objects that form the backbone of your application and that are managed by the Spring IoC container are called beans. A bean is an object that is instantiated, assembled,
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