The abnormal processing and error log record of the Javax Interceptor API framework
The abnormal processing and error log record of the Javax Interceptor API framework
The Javax Interceptor API is a interceptor framework defined in the Java Ee (Enterprise Edition) specification, which is used to intercept and process requests before and after the method execution.The interceptor can be used to achieve various functions, such as log records, abnormal processing, permissions verification, etc.
In this article, we will pay attention to the abnormal processing and error log records in the Javax Interceptor API framework.We will introduce how to capture and handle abnormalities in the interceptor and record abnormal information into an error log.
Abnormal treatment
In the interceptor, we can execute the custom abnormal processing logic by capturing abnormalities.The Javax Interableptor API provides an interface called ExceptionMapper, which can be used to define an abnormal processor.The following is an example code for an abnormal processor:
import javax.interceptor.AroundInvoke;
import javax.interceptor.InvocationContext;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
public class MyExceptionMapper implements ExceptionMapper<Exception> {
@Override
public Response toResponse(Exception exception) {
// Customized abnormal processing logic
// You can return a customized response, error page, etc.
return Response.status(Response.Status.INTERNAL_SERVER_ERROR)
.entity("An error occurred: " + exception.getMessage())
.build();
}
}
In the above example, we created an abnormal processor called MyexceptionMapper, implemented the ExceptionMapper interface, and specified Exception as generic parameters.In the Toresponse () method, we can perform the corresponding abnormal processing logic according to the abnormal type and return a customized response.
Error log record
In addition to handling abnormalities, we can also use the Javax Interceptor API framework to record the wrong log.In the interceptor, we can write the captured abnormal information into the error log file.
Below is a sample code that records the wrong log:
import javax.interceptor.AroundInvoke;
import javax.interceptor.InvocationContext;
import java.util.logging.Logger;
public class MyInterceptor {
private static final Logger logger = Logger.getLogger(MyInterceptor.class.getName());
@AroundInvoke
public Object logError(InvocationContext context) throws Exception {
try {
// The code executed before the method execution
return context.proceed();
} catch (Exception e) {
// Record the error log
logger.severe("An error occurred: " + e.getMessage());
throw e;
}
}
}
In the above example, we created a interceptor called MyInterceptor and used the Logger of JDK to record the wrong log.In the Logerror () method, we capture abnormalities before the method execution, and record the abnormal information through the logger into the error log.We can then choose to continue to throw abnormalities, or deal with abnormalities.
Configuration interceptor
To use the Javax Interceptor API framework for abnormal processing and error log records, you need to perform some configuration.Here are some of the main configuration steps:
1. In your Java EE project, create a interceptor class that implements the Interceptor interface (such as MyInterceptor in the above example).
2. In the interceptor class, the relevant interception logic is achieved according to your needs, such as abnormal processing and error log records.
3. Use the @Interceptor annotation to mark the interceptor class as a interceptor.
4. Related classes in your Java EE project (such as the JAX-RS Resource class) or method use @InterCeptors annotations to specify the interceptor.
Through these configuration steps, your interceptor will intercept requests before and after the relevant class or methods, and execute your custom interception logic, including abnormal processing and error log records.
Summarize
The Javax Interceptor API framework provides a convenient way to achieve abnormal processing and error log records.By using the ExceptionMapper interface and interceptor, we can capture and process abnormalities and record an exception information into an error log.The configuration steps are simple and easy to understand, which can help developers better manage and handle abnormal conditions.
