[WFLY-15366] split and simplify DataSourceMultipleConnStatsTestCase

https://issues.redhat.com/browse/WFLY-15366

The test case was unstable because of missing `ExecutorService.awaitTermination` in the first test so there could still be active requests that could interfere with the second test. Also tests in this test case tested different scenarios with different configurations so I split them into two test cases with two setup tasks. I also removed the asynchronous calls to the servlet. The second test doesn't need an asynchronous call, and the first test only need to add a connection request to queue.

testsuite/integration/basic/src/test/java/org/jboss/as/test/integration/jca/statistics/AbstractDataSourcePoolStatisticsTestCase.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright The WildFly Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.jboss.as.test.integration.jca.statistics;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.util.Set;
+import java.util.concurrent.CopyOnWriteArraySet;
+import javax.sql.DataSource;
+
+import jakarta.annotation.Resource;
+import org.jboss.arquillian.test.api.ArquillianResource;
+import org.jboss.as.arquillian.container.ManagementClient;
+import org.jboss.as.controller.PathAddress;
+import org.jboss.as.controller.client.helpers.Operations;
+import org.jboss.as.controller.operations.common.Util;
+import org.jboss.dmr.ModelNode;
+
+public abstract class AbstractDataSourcePoolStatisticsTestCase {
+
+    private Set<Connection> connections = new CopyOnWriteArraySet<>();
+
+    @ArquillianResource
+    protected ManagementClient managementClient;
+
+    @Resource(lookup = "java:jboss/datasources/ExampleDS")
+    private DataSource dataSource;
+
+    // /subsystem=datasources/data-source=ExampleDS/statistics=pool:read-attribute(name=AvailableCount)
+    protected int readStatisticsAttribute(String attributeName) throws Exception {
+        PathAddress statisticsPathAddress = PathAddress.parseCLIStyleAddress("/subsystem=datasources/data-source=ExampleDS/statistics=pool");
+        ModelNode readAttributeOperation = Util.getReadAttributeOperation(statisticsPathAddress, attributeName);
+
+        ModelNode result = managementClient.getControllerClient().execute(readAttributeOperation);
+        assertThat("Failed to read statistics: " + result, Operations.isSuccessfulOutcome(result), is(true));
+        return Operations.readResult(result).asInt();
+    }
+
+    // /subsystem=datasources/data-source=ExampleDS/statistics=pool/clear-statistics
+    protected void clearStatistics() throws Exception {
+        PathAddress statisticsPathAddress = PathAddress.parseCLIStyleAddress("/subsystem=datasources/data-source=ExampleDS/statistics=pool/");
+        ModelNode operation = Util.createOperation("clear-statistics", statisticsPathAddress);
+        ModelNode result = managementClient.getControllerClient().execute(operation);
+        assertThat("Failed to configure connection pool: " + result, Operations.isSuccessfulOutcome(result), is(true));
+    }
+
+    protected void allocateConnection() throws SQLException {
+        connections.add(dataSource.getConnection());
+    }
+
+    protected void clearConnections() {
+        connections.forEach(connection -> {
+            try {
+                connection.close();
+            } catch (SQLException sqle) {
+                throw new RuntimeException(sqle);
+            }
+        });
+    }
+}