HBASE-12218 Make HBaseCommonTestingUtil#deleteDir try harder

hbase-common/src/test/java/org/apache/hadoop/hbase/HBaseCommonTestingUtility.java

@@ -52,6 +52,7 @@ public class HBaseCommonTestingUtility {
 
   /**
    * Returns this classes's instance of {@link Configuration}.
+   *
    * @return Instance of Configuration.
    */
   public Configuration getConfiguration() {
@@ -69,14 +70,15 @@ public class HBaseCommonTestingUtility {
    */
   public static final String DEFAULT_BASE_TEST_DIRECTORY = "target/test-data";
 
-  /** Directory where we put the data for this instance of HBaseTestingUtility*/
+  /**
+   * Directory where we put the data for this instance of HBaseTestingUtility
+   */
   private File dataTestDir = null;
 
   /**
    * @return Where to write test data on local filesystem, specific to
    * the test.  Useful for tests that do not use a cluster.
    * Creates it if it does not exist already.
-   * @see #getTestFileSystem()
    */
   public Path getDataTestDir() {
     if (this.dataTestDir == null) {
@@ -166,7 +168,6 @@ public class HBaseCommonTestingUtility {
    * Should not be used by the unit tests, hence its's private.
    * Unit test will use a subdirectory of this directory.
    * @see #setupDataTestDir()
-   * @see #getTestFileSystem()
    */
   private Path getBaseTestDir() {
     String PathName = System.getProperty(
@@ -184,12 +185,18 @@ public class HBaseCommonTestingUtility {
     if (dir == null || !dir.exists()) {
       return true;
     }
+    int ntries = 0;
+    do {
+      ntries += 1;
       try {
         if (deleteOnExit()) FileUtils.deleteDirectory(dir);
         return true;
       } catch (IOException ex) {
         LOG.warn("Failed to delete " + dir.getAbsolutePath());
-      return false;
-    }
+      } catch (IllegalArgumentException ex) {
+        LOG.warn("Failed to delete " + dir.getAbsolutePath(), ex);
+      }
+    } while (ntries < 30);
+    return ntries < 30;
   }
 }