private List readChunks()

in src/main/java/org/apache/commons/imaging/formats/png/PngImageParser.java [649:720]
61 lines of code
20 McCabe index (conditional complexity)

    private List<PngChunk> readChunks(final InputStream is, final ChunkType[] chunkTypes,
            final boolean returnAfterFirst) throws ImagingException, IOException {
        final List<PngChunk> result = new ArrayList<>();

        while (true) {
            final int length = BinaryFunctions.read4Bytes("Length", is, "Not a Valid PNG File", getByteOrder());
            if (length < 0) {
                throw new ImagingException("Invalid PNG chunk length: " + length);
            }
            final int chunkType = BinaryFunctions.read4Bytes("ChunkType", is, "Not a Valid PNG File", getByteOrder());

            if (LOGGER.isLoggable(Level.FINEST)) {
                BinaryFunctions.logCharQuad("ChunkType", chunkType);
                debugNumber("Length", length, 4);
            }
            final boolean keep = keepChunk(chunkType, chunkTypes);

            byte[] bytes = null;
            if (keep) {
                bytes = BinaryFunctions.readBytes("Chunk Data", is, length,
                        "Not a Valid PNG File: Couldn't read Chunk Data.");
            } else {
                BinaryFunctions.skipBytes(is, length, "Not a Valid PNG File");
            }

            if (LOGGER.isLoggable(Level.FINEST)) {
                if (bytes != null) {
                    debugNumber("bytes", bytes.length, 4);
                }
            }

            final int crc = BinaryFunctions.read4Bytes("CRC", is, "Not a Valid PNG File", getByteOrder());

            if (keep) {
                if (chunkType == ChunkType.iCCP.value) {
                    result.add(new PngChunkIccp(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.tEXt.value) {
                    result.add(new PngChunkText(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.zTXt.value) {
                    result.add(new PngChunkZtxt(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.IHDR.value) {
                    result.add(new PngChunkIhdr(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.PLTE.value) {
                    result.add(new PngChunkPlte(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.pHYs.value) {
                    result.add(new PngChunkPhys(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.sCAL.value) {
                    result.add(new PngChunkScal(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.IDAT.value) {
                    result.add(new PngChunkIdat(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.gAMA.value) {
                    result.add(new PngChunkGama(length, chunkType, crc, bytes));
                } else if (chunkType == ChunkType.iTXt.value) {
                    result.add(new PngChunkItxt(length, chunkType, crc, bytes));
                } else {
                    result.add(new PngChunk(length, chunkType, crc, bytes));
                }

                if (returnAfterFirst) {
                    return result;
                }
            }

            if (chunkType == ChunkType.IEND.value) {
                break;
            }

        }

        return result;

    }