Merge pull request #3015 from ebean-orm/fix/3012-shutdown-leak

Fix for #3012 Manual server shutdown leads to memory leak

ebean-api/src/main/java/io/ebean/event/ShutdownManager.java

@@ -143,7 +143,7 @@ public final class ShutdownManager {
       }
       // shutdown any registered servers that have not
       // already been shutdown manually
-      for (Database server : databases) {
+      for (Database server : new ArrayList<>(databases)) {
         try {
           server.shutdown();
         } catch (Exception ex) {

ebean-core/src/main/java/io/ebeaninternal/server/core/DefaultServer.java

@@ -354,50 +354,35 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
 
   @Override
   public void shutdown() {
-    lock.lock();
-    try {
-      shutdownInternal(true, false);
-    } finally {
-      lock.unlock();
-    }
+    shutdown(true, false);
   }
 
-  /**
-   * Shutting down manually.
-   */
   @Override
   public void shutdown(boolean shutdownDataSource, boolean deregisterDriver) {
     lock.lock();
     try {
       ShutdownManager.unregisterDatabase(this);
-      shutdownInternal(shutdownDataSource, deregisterDriver);
+      log.log(TRACE, "shutting down instance {0}", serverName);
+      if (shutdown) {
+        // already shutdown
+        return;
+      }
+      shutdownPlugins();
+      autoTuneService.shutdown();
+      // shutdown background threads
+      backgroundExecutor.shutdown();
+      // shutdown DataSource (if its an Ebean one)
+      transactionManager.shutdown(shutdownDataSource, deregisterDriver);
+      dumpMetrics();
+      shutdown = true;
+      if (shutdownDataSource) {
+        config.setDataSource(null);
+      }
     } finally {
       lock.unlock();
     }
   }
 
-  /**
-   * Shutdown the services like threads and DataSource.
-   */
-  private void shutdownInternal(boolean shutdownDataSource, boolean deregisterDriver) {
-    log.log(TRACE, "shutting down instance {0}", serverName);
-    if (shutdown) {
-      // already shutdown
-      return;
-    }
-    shutdownPlugins();
-    autoTuneService.shutdown();
-    // shutdown background threads
-    backgroundExecutor.shutdown();
-    // shutdown DataSource (if its an Ebean one)
-    transactionManager.shutdown(shutdownDataSource, deregisterDriver);
-    dumpMetrics();
-    shutdown = true;
-    if (shutdownDataSource) {
-      config.setDataSource(null);
-    }
-  }
-
   private void dumpMetrics() {
     if (config.isDumpMetricsOnShutdown()) {
       new DumpMetrics(this, config.getDumpMetricsOptions()).dump();

ebean-ddl-generator/src/test/java/io/ebeaninternal/dbmigration/model/build/ModelBuild_explicitSequencesTest.java

@@ -1,13 +1,13 @@
 package io.ebeaninternal.dbmigration.model.build;
 
 
-import io.localtest.BaseTestCase;
 import io.ebean.DatabaseFactory;
 import io.ebean.config.DatabaseConfig;
 import io.ebeaninternal.api.SpiEbeanServer;
 import io.ebeaninternal.dbmigration.ddlgeneration.DdlOptions;
 import io.ebeaninternal.dbmigration.ddlgeneration.Helper;
 import io.ebeaninternal.dbmigration.model.CurrentModel;
+import io.localtest.BaseTestCase;
 import org.junit.jupiter.api.Test;
 import org.tests.model.basic.Person;
 import org.tests.model.basic.Phone;
@@ -66,7 +66,7 @@ class ModelBuild_explicitSequencesTest extends BaseTestCase {
         .startsWith("-- Generated by ebean")
         .endsWith(Helper.asText(this, "/assert/ModelBuild_explicitSequencesTest/pg-apply.sql"));
     } finally {
-      ebeanServer.shutdown();
+      ebeanServer.shutdown(true, false);
     }
   }