#vulnerable code 
                                @Override
    public void batchStarted(MiniBatchOperationInProgress<Mutation> miniBatchOp, IndexMetaData context) throws IOException {
        // The entire purpose of this method impl is to get the existing rows for the
        // table rows being indexed into the block cache, as the index maintenance code
        // does a point scan per row.
        List<IndexMaintainer> indexMaintainers = ((PhoenixIndexMetaData)context).getIndexMaintainers();
        List<KeyRange> keys = Lists.newArrayListWithExpectedSize(miniBatchOp.size());
        Map<ImmutableBytesWritable, IndexMaintainer> maintainers =
                new HashMap<ImmutableBytesWritable, IndexMaintainer>();
        ImmutableBytesWritable indexTableName = new ImmutableBytesWritable();
        for (int i = 0; i < miniBatchOp.size(); i++) {
            Mutation m = miniBatchOp.getOperation(i);
            keys.add(PVarbinary.INSTANCE.getKeyRange(m.getRow()));
            
            for(IndexMaintainer indexMaintainer: indexMaintainers) {
                if (indexMaintainer.isImmutableRows()) continue;
                indexTableName.set(indexMaintainer.getIndexTableName());
                if (maintainers.get(indexTableName) != null) continue;
                maintainers.put(indexTableName, indexMaintainer);
            }

        }
        if (maintainers.isEmpty()) return;
        Scan scan = IndexManagementUtil.newLocalStateScan(new ArrayList<IndexMaintainer>(maintainers.values()));
        ScanRanges scanRanges = ScanRanges.createPointLookup(keys);
        scanRanges.initializeScan(scan);
        scan.setFilter(new SkipScanFilter(scanRanges.getSkipScanFilter(),true));
        Region region = env.getRegion();
        RegionScanner scanner = region.getScanner(scan);
        // Run through the scanner using internal nextRaw method
        region.startRegionOperation();
        try {
            synchronized (scanner) {
                boolean hasMore;
                do {
                    List<Cell> results = Lists.newArrayList();
                    // Results are potentially returned even when the return value of s.next is
                    // false since this is an indication of whether or not there are more values
                    // after the ones returned
                    hasMore = scanner.nextRaw(results);
                } while (hasMore);
            }
        } finally {
            try {
                scanner.close();
            } finally {
                region.closeRegionOperation();
            }
        }
    } 
                            #location 25 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                                @Override
    public void batchStarted(MiniBatchOperationInProgress<Mutation> miniBatchOp, IndexMetaData context) throws IOException {
    }