Hands-On High Performance with Spring 5

Spring's IoC container

Spring's IoC container is built as the core module of the Spring architecture. IoC is also known as DI. It is a design pattern which eliminates the dependency of the code to provide ease in managing and testing the application. In DI, the objects themselves characterize their dependencies with the other objects they work, just through constructor arguments, arguments to a factory method, or properties that are set on the object instance after it is created or returned from a factory method. 

The container is then responsible to inject those dependencies when it creates the bean. This process is basically the inverse (so it is known as IoC) of the bean itself controlling the instantiation or location of its dependencies, ...