Update CcmBridge#getCurrentJvmMajorVersion to use regular expressions

test-infra/src/main/java/com/datastax/oss/driver/api/testinfra/ccm/CcmBridge.java

@@ -38,6 +38,8 @@
 import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import org.apache.commons.exec.CommandLine;
 import org.apache.commons.exec.DefaultExecutor;
@@ -47,6 +49,7 @@
 import org.apache.commons.exec.LogOutputStream;
 import org.apache.commons.exec.PumpStreamHandler;
 import org.assertj.core.util.Lists;
+import org.assertj.core.util.VisibleForTesting;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -111,6 +114,9 @@ public class CcmBridge implements AutoCloseable {
   private static final Version V3_0_15 = Version.parse("3.0.15");
   private static final Version V2_1_19 = Version.parse("2.1.19");
 
+  private static final Pattern JVM_VERSION_PATTERN =
+      Pattern.compile("^(1\\.)?(?<major>[0-9]+)\\..*$");
+
   static {
     if (DSE_ENABLEMENT) {
       LOG.info("CCM Bridge configured with DSE version {}", VERSION);
@@ -430,17 +436,18 @@ private static File createTempStore(String storePath) {
    *
    * @return major version of current JVM
    */
-  private static int getCurrentJvmMajorVersion() {
-    String version = System.getProperty("java.version");
-    if (version.startsWith("1.")) {
-      version = version.substring(2, 3);
-    } else {
-      int dot = version.indexOf(".");
-      if (dot != -1) {
-        version = version.substring(0, dot);
-      }
+  @VisibleForTesting
+  static int getCurrentJvmMajorVersion() {
+    return getJvmMajorVersion(System.getProperty("java.version"));
+  }
+
+  @VisibleForTesting
+  static int getJvmMajorVersion(String version) {
+    Matcher matcher = version != null ? JVM_VERSION_PATTERN.matcher(version) : null;
+    if (matcher == null || !matcher.matches() || matcher.group("major") == null) {
+      throw new IllegalStateException("Unable to parse JVM version: " + version);
     }
-    return Integer.parseInt(version);
+    return Integer.parseInt(matcher.group("major"));
   }
 
   private Optional<Integer> overrideJvmVersionForDseWorkloads() {

test-infra/src/test/java/com/datastax/oss/driver/api/testinfra/ccm/CcmBridgeTest.java

@@ -0,0 +1,80 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.datastax.oss.driver.api.testinfra.ccm;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
+
+import org.junit.Test;
+
+public class CcmBridgeTest {
+
+  @Test
+  public void should_parse_system_jvm() {
+    assertThat(CcmBridge.getCurrentJvmMajorVersion()).isGreaterThan(0);
+  }
+
+  @Test
+  public void should_parse_jvm_8_like() {
+    assertThat(CcmBridge.getJvmMajorVersion("1.8.0_181")).isEqualTo(8);
+  }
+
+  @Test
+  public void should_parse_jvm_8_like_with_trailing_alphabetic() {
+    assertThat(CcmBridge.getJvmMajorVersion("1.8.0_181_b1")).isEqualTo(8);
+  }
+
+  @Test
+  public void should_parse_jvm_11_like() {
+    assertThat(CcmBridge.getJvmMajorVersion("11.0.20.1")).isEqualTo(11);
+  }
+
+  @Test
+  public void should_parse_jvm_17_like() {
+    assertThat(CcmBridge.getJvmMajorVersion("17.0.8.1")).isEqualTo(17);
+  }
+
+  @Test
+  public void should_parse_jvm_21_like() {
+    assertThat(CcmBridge.getJvmMajorVersion("21.0.1")).isEqualTo(21);
+  }
+
+  @Test
+  public void should_fail_null_version() {
+    assertThatCode(() -> CcmBridge.getJvmMajorVersion(null))
+        .isInstanceOf(IllegalStateException.class);
+  }
+
+  @Test
+  public void should_fail_empty_version() {
+    assertThatCode(() -> CcmBridge.getJvmMajorVersion(""))
+        .isInstanceOf(IllegalStateException.class);
+  }
+
+  @Test
+  public void should_fail_non_number() {
+    assertThatCode(() -> CcmBridge.getJvmMajorVersion("abc"))
+        .isInstanceOf(IllegalStateException.class);
+  }
+
+  @Test
+  public void should_fail_not_versioned() {
+    assertThatCode(() -> CcmBridge.getJvmMajorVersion("8"))
+        .isInstanceOf(IllegalStateException.class);
+  }
+}