Use Microprofile Metrics API to monitor the Java library

Use Microprofile Metrics API to monitor the Java library Overview: As the promotion of microservices and the complexity of applications increases, it is becoming increasingly important for monitoring and measurement applications.Microprofile Metrics API is a powerful Java library to collect and report the function of measuring data on application status, performance and health data.This article will introduce how to use Microprofile Metrics API to monitor the Java library and provide some Java code examples. 1. Introduce dependencies First, we need to introduce the relevant dependence of MicroProfile Metrics API in the project.Add the following dependencies to the pom.xml file: <dependency> <groupId>org.eclipse.microprofile.metrics</groupId> <artifactId>microprofile-metrics-api</artifactId> <version>3.0</version> </dependency> 2. Create a custom index Next, we can use the MicroProfile Metrics API to create a custom indicator.For example, assuming that we want to monitor the number and method execution time of the method in a Java library, the following code can be used: import org.eclipse.microprofile.metrics.Counter; import org.eclipse.microprofile.metrics.MetricRegistry; import org.eclipse.microprofile.metrics.annotation.RegistryType; @RegistryType(type = MetricRegistry.Type.APPLICATION) public class MyLibraryMetrics { private final Counter methodCalls; private final Timer methodExecutionTime; public MyLibraryMetrics() { MetricRegistry registry = new MetricRegistry(); // Create a counter methodCalls = registry.counter("method.calls"); // Create a timer methodExecutionTime = registry.timer("method.execution.time"); } public void method1() { Methodcalls.inc (); // Add call number Timer.context context = METHODEXECUTINTIME.TIME (); // Start the time // Execution method logic // ... context.stop (); // Stop timing } public void method2() { Methodcalls.inc (); // Add call number Timer.context context = METHODEXECUTINTIME.TIME (); // Start the time // Execution method logic // ... context.stop (); // Stop timing } } In the above code, we use the two indicators of `Counter` and` Timer` to monitor the number and execution time of the monitoring method.First of all, we created a measuring registry through the `metricRegistry` class, and used the registry that marked it as an application level with the`@registryType` annotation.Then, we use the method of `Count ()` and the method of `Timer ()` to create the corresponding indicators.In the logic of each method, we can call the number of times by calling the `Inc ()` method, and use the `Time ()` method to start and stop the timing. 3. Export and report indicators Microprofile Metrics API provides multiple methods of exporting and reporting indicators.The following are some common methods: -JSON format: export the indicator to JSON format to facilitate the use of the system or data visualization tool. -Lometheus format: Export the indicator to the Prometheus format to integrate it with the Prometheus monitoring system. -JMX format: Export the indicators to the Java Management Extensions (JMX) in order to view it through the JConsole or JMX client. In order to use these export methods, we can add the corresponding exporter dependencies and perform some configurations in the configuration file of the application.Taking the export of the indicator as the JSON format as an example, we can follow the steps below: 1. Add dependencies: <dependency> <groupId>org.eclipse.microprofile.metrics</groupId> <artifactId>microprofile-metrics-api</artifactId> <version>3.0</version> </dependency> <dependency> <groupId>org.eclipse.microprofile.metrics</groupId> <artifactId>microprofile-metrics-json</artifactId> <version>3.0</version> </dependency> 2. Add the following configuration in the application configuration file: properties microprofile.metrics.export.json.enabled=true Now, our indicators will be exported in JSON format and can be viewed and analyzed using the corresponding tools. Summarize: Microprofile Metrics API is a powerful Java library that is used to collect and report application status, performance and health measurement data.This article introduces how to monitor the Java library with Microprofile Metrics API and provide corresponding Java code examples.Through reasonable use of the indicators and report mechanisms, we can better understand the performance and operating conditions of the application, thereby promptly optimizing and adjusting.