Javax Inject's application case analysis in the Java class library
Javax Inject's application case analysis in the Java class library
Javax Inject is an implementation of a dependencies in Java.Dependent injection is a design mode for dependent relationships between decoupled components, and provides maintenance and test -available code.Javax Inject provides a set of annotations that allow developers to declare dependency relationships in applications to achieve dependency injection.
In the Java class library, Javax Inject can be applied to various scenarios.The application of Javax Inject in the Java class library will be parsed by some examples.
1. Inversion of Control
Control reversal is a technology that avoids hard -coding dependencies in applications.By using @Inject annotations in Javax Inject, the dependency relationship can be removed from the code, so that the code can be more maintained and tested.
public class ExampleService {
@Inject
private ExampleRepository repository;
public void doSomething() {
// Use ExampleRePOSITORY instance to perform necessary operations
}
}
2. Dependency Resolution
In the Java library, sometimes the dependencies need to be parsed to other modules.@Inject Note in Javax Inject can help us automatically resolve dependencies.
public class ExampleModule {
private ExampleService service;
@Inject
public ExampleModule(ExampleService service) {
this.service = service;
}
// Other modules can obtain ExampleService examples through the ExampleModule class
}
3. Singleton (Singleton)
In some scenarios, we need to ensure that only one instance is created and shared with each module.@Singleton annotations in Javax Inject can be used to mark such a class.
@Singleton
public class ExampleSingleton {
// This class will only be instantiated once
public void doSomething() {
// ...
}
}
4. Lazy Initialization
Sometimes we hope that the instance that depends will be instantiated at the first use, rather than created during initialization.@Lazy annotations in Javax Inject can achieve delayed initialization.
public class ExampleService {
@Inject
@Lazy
private ExampleDependency dependency;
public void doSomething() {
// When the Dependency instance is first used for the first time, it will be initialized
}
}
Through the above example, we can see some typical applications of Javax Inject in the Java library.
Summarize:
Javax Inject is a specification for relying in injection in Java.It provides a set of annotations that allow developers to better manage the dependencies in the coupling application.By using Javax Inject, we can realize functions such as controlling reversal, dependence analysis, singles mode, and delay initialization, thereby improving the maintenance and testability of the code.