Fix violations reported by SonarQube: preserve stacktrace, final class.

Jean-Noel Rouvignac

25.42.2015 26e802d6fa4cb1dddd4764a931169f0be0effd61

 opendj-server-legacy/src/main/java/org/opends/server/backends/pluggable/AttributeIndex.java

@@ -1116,10 +1116,8 @@
    return false;
  }

  /**
   * This class extends the IndexConfig for JE Backend.
   */
  private class JEIndexConfig implements IndexingOptions
  /** This class extends the IndexConfig for JE Backend. */
  private final class JEIndexConfig implements IndexingOptions
  {
    /** The length of the substring index. */
    private int substringLength;