public int read()

in priam/src/main/java/com/netflix/priam/backup/RangeReadInputStream.java [50:87]

• 35 lines of code
• 8 McCabe index (conditional complexity)

    public int read(final byte b[], final int off, final int len) throws IOException {
        if (fileSize > 0 && offset >= fileSize) return -1;
        final long firstByte = offset;
        long curEndByte = firstByte + len;
        curEndByte = curEndByte <= fileSize ? curEndByte : fileSize;

        // need to subtract one as the call to getRange is inclusive
        // meaning if you want to download the first 10 bytes of a file, request bytes 0..9
        final long endByte = curEndByte - 1;
        try {
            return new RetryableCallable<Integer>() {
                public Integer retriableCall() throws IOException {
                    GetObjectRequest req = new GetObjectRequest(bucketName, remotePath);
                    req.setRange(firstByte, endByte);
                    try (S3ObjectInputStream is = s3Client.getObject(req).getObjectContent()) {
                        byte[] readBuf = new byte[4092];
                        int rCnt;
                        int readTotal = 0;
                        int incomingOffet = off;
                        while ((rCnt = is.read(readBuf, 0, readBuf.length)) >= 0) {
                            System.arraycopy(readBuf, 0, b, incomingOffet, rCnt);
                            readTotal += rCnt;
                            incomingOffet += rCnt;
                        }
                        if (readTotal == 0 && rCnt == -1) return -1;
                        offset += readTotal;
                        return readTotal;
                    }
                }
            }.call();
        } catch (Exception e) {
            String msg =
                    String.format(
                            "failed to read offset range %d-%d of file %s whose size is %d",
                            firstByte, endByte, remotePath, fileSize);
            throw new IOException(msg, e);
        }
    }