public int compareIndexData(IndexType indexType, String[] indexDefinitions,
      String indexExpression, IndexType otherType, String[] otherDefinitions,
      String otherExpression, int[] mapping) {

    int matchLevel = -2;

    if (indexExpression.equals(otherExpression) && indexType == otherType) {
      /* Asif : A match level of zero means exact match. */
      matchLevel = getMatchLevel(otherDefinitions, indexDefinitions, mapping);
    }
    return matchLevel;
  }
Get the Index with the specified indexType, fromClause, indexedExpression TODO: Asif :Check if
synchronization is needed while obtaining Array of Indexes as similar to what we have used
during index updates. This function will get the exact index , if available, else will return
null

@param indexType the type of index
@param definitions the String array containing the required defintions of the fromClause of the
       index
@param indexedExpression the indexedExpression for the index
@param context ExecutionContext
@return the sole index of the region with these parameters, or null if there isn't one
geode-core/src/main/java/org/apache/geode/cache/query/internal/index/IndexManager.java