- Fix memory leak.

- Add code's line-numbers in the logs.

src/main/java/eu/dnetlib/repo/manager/controllers/PrometheusController.java

@@ -51,7 +51,11 @@ public class PrometheusController { // TODO: remove this with migration to Sprin
     public String getMetrics() {
         PrometheusMeterRegistry registry = new PrometheusMeterRegistry(PrometheusConfig.DEFAULT);
         new JvmThreadMetrics().bindTo(registry);
-        new JvmGcMetrics().bindTo(registry);
+        try (JvmGcMetrics jvmGcMetrics = new JvmGcMetrics() ) {
+            jvmGcMetrics.bindTo(registry);
+        } catch (Exception e) {
+            LOGGER.error("", e);
+        }
         new JvmMemoryMetrics().bindTo(registry);
         new DiskSpaceMetrics(new File("/")).bindTo(registry);
         new ProcessorMetrics().bindTo(registry); // metrics related to the CPU stats

src/main/resources/log4j2.xml

@@ -2,7 +2,7 @@
 <Configuration status="DEBUG">
     <Appenders>
         <Console name="LogToConsole" target="SYSTEM_OUT">
-            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %highlight{%-5level} %logger{36} - %msg%n"/>
+            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %highlight{%-5level} %logger{36}.%M\(@%line\) - %msg%n"/>
         </Console>
     </Appenders>
     <Loggers>