Remove circular dependency and do not init class

Author: JackBuggins

hadoop-common-project/hadoop-auth/src/main/java/org/apache/hadoop/util/PlatformName.java

@@ -49,23 +49,18 @@ public class PlatformName {
    * own implementations of many security packages and Cipher suites.
    * Note that these are not provided in Semeru runtimes:
    * See https://developer.ibm.com/languages/java/semeru-runtimes/
+   * The class used is present in any supported IBM JTE Runtimes.
    */
-  public static final boolean IBM_JAVA = shouldUseIbmPackages();
+  public static final boolean IBM_JAVA = JAVA_VENDOR_NAME.contains("IBM") &&
+    hasClass("com.ibm.security.auth.module.JAASLoginModule");
 
-  private static boolean shouldUseIbmPackages() {
-    if (JAVA_VENDOR_NAME.contains("IBM")) {
-      try {
-        /**
-         * This class is provided by all supported IBM JTE Runtimes,
-         * but ensures we do not make assumptions of existence of
-         * specialised security modules based on vendor alone.
-         */
-        Class.forName("com.ibm.security.auth.module.JAASLoginModule");
-        return true;
-      } catch(ClassNotFoundException ignored) {}
+  private static boolean hasClass(String className) {
+    try {
+      Thread.currentThread().getContextClassLoader().loadClass(className);
+      return true;
+    } catch(ClassNotFoundException ignored) {
+      return false;
     }
-
-    return false;
   }
 
   public static void main(String[] args) {

hadoop-common-project/hadoop-minikdc/pom.xml

@@ -48,11 +48,6 @@
       <artifactId>junit</artifactId>
       <scope>compile</scope>
     </dependency>
-    <dependency>
-      <groupId>org.apache.hadoop</groupId>
-      <artifactId>hadoop-auth</artifactId>
-      <scope>test</scope>
-    </dependency>
   </dependencies>
 
   <build>

hadoop-common-project/hadoop-minikdc/src/test/java/org/apache/hadoop/minikdc/TestMiniKdc.java

@@ -37,9 +37,19 @@
 import java.util.HashMap;
 import java.util.Arrays;
 
-import static org.apache.hadoop.util.PlatformName.IBM_JAVA;
-
 public class TestMiniKdc extends KerberosSecurityTestcase {
+  private static final boolean IBM_JAVA = shouldUseIbmPackages();
+
+  private static boolean shouldUseIbmPackages() {
+    if (System.getProperty("java.vendor").contains("IBM")) {
+      try {
+        Class.forName("com.ibm.security.auth.module.JAASLoginModule");
+        return true;
+      } catch(ClassNotFoundException ignored) {}
+    }
+
+    return false;
+  }
 
   @Test
   public void testMiniKdcStart() {