Microprofile Metrics API: The measurement interface in the Java class library

Microprofile Metrics API is a Java class library for measurement and monitoring application performance.It provides a set of interfaces and annotations that enable developers to easily collect, record and display the performance indicators of applications. It is very simple to use Microprofile Metrics API in applications.First of all, we need to add the dependency item of Microprofile Metrics API to our project.The specific dependencies can be different according to the construction tool we use.In Maven, we can add the following dependencies to our pom.xml file: <dependency> <groupId>org.eclipse.microprofile.metrics</groupId> <artifactId>microprofile-metrics-api</artifactId> <version>3.0</version> </dependency> Once we add dependencies, we can start using Microprofile Metrics API.First of all, we need to create a Metricregition object, which is the center of our record and management measurement index.We can inject the Metricregition object into our application or create it manually where we need it. import org.eclipse.microprofile.metrics.MetricRegistry; public class MyApplication { private static MetricRegistry metricRegistry = new MetricRegistry(); public static void main(String[] args) { // Application logic // Create a counter index Counter counter = metricRegistry.counter("myapp.counter"); // Increase the value of the counter counter.inc(); // Create a timer indicator Timer timer = metricRegistry.timer("myapp.timer"); // start the timer Timer.Context timerContext = timer.time(); // Application logic (for example, perform a certain task) // Stop timing timerContext.stop(); // Register other types of indicators (for example, histogram, instrument panel, etc.) // Display the statistical information of the measurement index metricRegistry.getMetrics().forEach((name, metric) -> { System.out.println(name + ": " + metric); }); } } In the above example, we first created a Metricregition object.We then used this object to create a counter indicator and a timer indicator.We can use the counting indicator to track the number of execution times in the application, and the timer indicator can be used to measure the execution time of a certain operation.In the logic of the application, we increase the value of the counter and timing the timer indicator.Finally, we showed statistical information of all registered measurement indicators. Microprofile Metrics API also provides other types of measurement indicators, such as histogram, dashboard, etc.We can choose the appropriate measurement index according to specific needs. In summary, Microprofile Metrics API is a powerful and flexible Java class library that can be used to measure and monitor application performance.By using the interfaces and annotations provided, developers can easily record and display the performance indicators of the application, so as to better understand and optimize the performance of the application.