Detailed analysis of the Javax Internet

The Javax Interceptor API is a standard API in Java for intercepting and executing additional operations before and after the method call. It provides a simple and flexible way to achieve the function of cross -sectional attention.In this article, we will introduce the usage and related configuration of the Javax Interceptor API. The main purpose of the Javax Internet is to capture the method by defining the interceptor class and perform additional logic before and after the method call.The interceptor can be used for various cross -sectional attention points such as logging, performance statistics, and security verification. To use the Javax Interceptor API, you need to define a interceptor first. This class must implement javax.interceptor.inVocationContext interface.The InvoCATIONTEXT interface provides information such as parameters, method signatures, and return values of access target methods. The following is an interceptor class of an example: import javax.interceptor.AroundInvoke; import javax.interceptor.Interceptor; import javax.interceptor.InvocationContext; @Interceptor public class LoggingInterceptor { @AroundInvoke public Object logMethod(InvocationContext context) throws Exception { System.out.println("Entering method: " + context.getMethod().getName()); Object result = context.proceed(); System.out.println("Exiting method: " + context.getMethod().getName()); return result; } } In the above example, we define a interceptor called LoggingInterceptor.This class is marked as a @Interceptor annotation, indicating that it is a interceptor.The logmethod method in the interceptor uses @Aaroundinvoke annotations to mark it, indicating that it will be executed before and after the target method calls.In the logmethod method, we can write any logic you want to execute, such as printing logs. To use the interceptor in the application, we need to mark the @Interceptors annotation on the target class or method and specify the array of the interceptor class.The following is an example: import javax.ejb.Stateless; import javax.interceptor.Interceptors; @Stateless @Interceptors(LoggingInterceptor.class) public class ExampleService { public void doSomething() { // Execute some business logic } } In the above example, the ExampleService class is marked as @Stateless, indicating that it is an stateless EJB.We also use the @InterCeptors annotation to apply the loggingInterceptor interceptor to the Exampleservice class.This means that before and after calling any method of calling the Exampleservice class, the logging of LogmentInterceptor will be executed. In order to obtain an instance of the interceptor in the vessel, we also need to configure related configuration in the application.The specific configuration steps may be different due to different applications.A common configuration method is to declare the interceptor in the application's web.xml or ejb-jar.xml file.The following is a web.xml configuration of an example: <web-app> ... <interceptors> <interceptor> <interceptor-class>com.example.LoggingInterceptor</interceptor-class> </interceptor> </interceptors> ... </web-app> In the above example, we declare a interceptor named LoggingInterceptor.With this configuration, the container will be able to use the loggingInterceptor interceptor in the application. In summary, the Javax Interceptor API provides a simple and flexible way to achieve the function of cross -sectional attention.By defining the interceptor class and applying @Interceptors annotations in the target class or method, we can capture the method call and perform additional operations before and after calling.The interceptor can be used for various needs such as logging, performance statistics, and security verification.To use the Javax Interceptor API, you also need to configure related configurations in the application.