public List cleanupAndGetValidFiles()

in hyracks/hyracks-storage-am-lsm-rtree/src/main/java/org/apache/hyracks/storage/am/lsm/rtree/impls/LSMRTreeFileManager.java [95:198]
82 lines of code
22 McCabe index (conditional complexity)

    public List<LSMComponentFileReferences> cleanupAndGetValidFiles() throws HyracksDataException, IndexException {
        List<LSMComponentFileReferences> validFiles = new ArrayList<LSMComponentFileReferences>();
        ArrayList<ComparableFileName> allRTreeFiles = new ArrayList<ComparableFileName>();
        ArrayList<ComparableFileName> allBTreeFiles = new ArrayList<ComparableFileName>();
        ArrayList<ComparableFileName> allBloomFilterFiles = new ArrayList<ComparableFileName>();

        // Create a transaction filter <- to hide transaction components->
        FilenameFilter transactionFilter = getTransactionFileFilter(false);

        // Gather files.
        cleanupAndGetValidFilesInternal(getCompoundFilter(transactionFilter, btreeFilter), btreeFactory, allBTreeFiles);
        HashSet<String> btreeFilesSet = new HashSet<String>();
        for (ComparableFileName cmpFileName : allBTreeFiles) {
            int index = cmpFileName.fileName.lastIndexOf(SPLIT_STRING);
            btreeFilesSet.add(cmpFileName.fileName.substring(0, index));
        }
        validateFiles(btreeFilesSet, allRTreeFiles, getCompoundFilter(transactionFilter, rtreeFilter), rtreeFactory);
        validateFiles(btreeFilesSet, allBloomFilterFiles, getCompoundFilter(transactionFilter, bloomFilterFilter), null);

        // Sanity check.
        if (allRTreeFiles.size() != allBTreeFiles.size() || allBTreeFiles.size() != allBloomFilterFiles.size()) {
            throw new HyracksDataException(
                    "Unequal number of valid RTree, BTree, and Bloom Filter files found. Aborting cleanup.");
        }

        // Trivial cases.
        if (allRTreeFiles.isEmpty() || allBTreeFiles.isEmpty() || allBloomFilterFiles.isEmpty()) {
            return validFiles;
        }

        if (allRTreeFiles.size() == 1 && allBTreeFiles.size() == 1 && allBloomFilterFiles.size() == 1) {
            validFiles.add(new LSMComponentFileReferences(allRTreeFiles.get(0).fileRef, allBTreeFiles.get(0).fileRef,
                    allBloomFilterFiles.get(0).fileRef));
            return validFiles;
        }

        // Sorts files names from earliest to latest timestamp.
        Collections.sort(allRTreeFiles);
        Collections.sort(allBTreeFiles);
        Collections.sort(allBloomFilterFiles);

        List<ComparableFileName> validComparableRTreeFiles = new ArrayList<ComparableFileName>();
        ComparableFileName lastRTree = allRTreeFiles.get(0);
        validComparableRTreeFiles.add(lastRTree);

        List<ComparableFileName> validComparableBTreeFiles = new ArrayList<ComparableFileName>();
        ComparableFileName lastBTree = allBTreeFiles.get(0);
        validComparableBTreeFiles.add(lastBTree);

        List<ComparableFileName> validComparableBloomFilterFiles = new ArrayList<ComparableFileName>();
        ComparableFileName lastBloomFilter = allBloomFilterFiles.get(0);
        validComparableBloomFilterFiles.add(lastBloomFilter);

        for (int i = 1; i < allRTreeFiles.size(); i++) {
            ComparableFileName currentRTree = allRTreeFiles.get(i);
            ComparableFileName currentBTree = allBTreeFiles.get(i);
            ComparableFileName currentBloomFilter = allBloomFilterFiles.get(i);
            // Current start timestamp is greater than last stop timestamp.
            if (currentRTree.interval[0].compareTo(lastRTree.interval[1]) > 0
                    && currentBTree.interval[0].compareTo(lastBTree.interval[1]) > 0
                    && currentBloomFilter.interval[0].compareTo(lastBloomFilter.interval[1]) > 0) {
                validComparableRTreeFiles.add(currentRTree);
                validComparableBTreeFiles.add(currentBTree);
                validComparableBloomFilterFiles.add(currentBloomFilter);
                lastRTree = currentRTree;
                lastBTree = currentBTree;
                lastBloomFilter = currentBloomFilter;
            } else if (currentRTree.interval[0].compareTo(lastRTree.interval[0]) >= 0
                    && currentRTree.interval[1].compareTo(lastRTree.interval[1]) <= 0
                    && currentBTree.interval[0].compareTo(lastBTree.interval[0]) >= 0
                    && currentBTree.interval[1].compareTo(lastBTree.interval[1]) <= 0
                    && currentBloomFilter.interval[0].compareTo(lastBloomFilter.interval[0]) >= 0
                    && currentBloomFilter.interval[1].compareTo(lastBloomFilter.interval[1]) <= 0) {
                // Invalid files are completely contained in last interval.
                File invalidRTreeFile = new File(currentRTree.fullPath);
                invalidRTreeFile.delete();
                File invalidBTreeFile = new File(currentBTree.fullPath);
                invalidBTreeFile.delete();
                File invalidBloomFilterFile = new File(currentBloomFilter.fullPath);
                invalidBloomFilterFile.delete();
            } else {
                // This scenario should not be possible.
                throw new HyracksDataException("Found LSM files with overlapping but not contained timetamp intervals.");
            }
        }

        // Sort valid files in reverse lexicographical order, such that newer
        // files come first.
        Collections.sort(validComparableRTreeFiles, recencyCmp);
        Collections.sort(validComparableBTreeFiles, recencyCmp);
        Collections.sort(validComparableBloomFilterFiles, recencyCmp);

        Iterator<ComparableFileName> rtreeFileIter = validComparableRTreeFiles.iterator();
        Iterator<ComparableFileName> btreeFileIter = validComparableBTreeFiles.iterator();
        Iterator<ComparableFileName> bloomFilterFileIter = validComparableBloomFilterFiles.iterator();
        while (rtreeFileIter.hasNext() && btreeFileIter.hasNext()) {
            ComparableFileName cmpRTreeFileName = rtreeFileIter.next();
            ComparableFileName cmpBTreeFileName = btreeFileIter.next();
            ComparableFileName cmpBloomFilterFileName = bloomFilterFileIter.next();
            validFiles.add(new LSMComponentFileReferences(cmpRTreeFileName.fileRef, cmpBTreeFileName.fileRef,
                    cmpBloomFilterFileName.fileRef));
        }
        return validFiles;
    }