public PNGImage()

in src/main/java/org/apache/xmlgraphics/image/codec/png/PNGImageDecoder.java [343:478]
116 lines of code
30 McCabe index (conditional complexity)

    public PNGImage(InputStream stream, PNGDecodeParam decodeParam)
        throws IOException {

        if (!stream.markSupported()) {
            stream = new BufferedInputStream(stream);
        }
        DataInputStream distream = new DataInputStream(stream);

        if (decodeParam == null) {
            decodeParam = new PNGDecodeParam();
        }
        this.decodeParam = decodeParam;

        // Get parameter values
        this.suppressAlpha = decodeParam.getSuppressAlpha();
        this.expandPalette = decodeParam.getExpandPalette();
        this.output8BitGray = decodeParam.getOutput8BitGray();
        this.expandGrayAlpha = decodeParam.getExpandGrayAlpha();
        if (decodeParam.getPerformGammaCorrection()) {
            this.userExponent = decodeParam.getUserExponent();
            this.displayExponent = decodeParam.getDisplayExponent();
            performGammaCorrection = true;
            output8BitGray = true;
        }
        this.generateEncodeParam = decodeParam.getGenerateEncodeParam();

        if (emitProperties) {
            properties.put("file_type", "PNG v. 1.0");
        }

        try {
            long magic = distream.readLong();
            if (magic != PNG_SIGNATURE) {
                String msg = PropertyUtil.getString("PNGImageDecoder0");
                throw new RuntimeException(msg);
            }
        } catch (IOException ioe) {
            ioe.printStackTrace();
            String msg = PropertyUtil.getString("PNGImageDecoder1");
            throw new RuntimeException(msg);
        }

        do {
//            try {
                PNGChunk chunk;

                String chunkType = PNGChunk.getChunkType(distream);
                if (chunkType.equals(PNGChunk.ChunkType.IHDR.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_IHDR_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.PLTE.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_PLTE_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.IDAT.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    streamVec.add(new ByteArrayInputStream(chunk.getData()));
                } else if (chunkType.equals(PNGChunk.ChunkType.IEND.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    try {
                        parse_IEND_chunk(chunk);
                    } catch (Exception e) {
                        e.printStackTrace();
                        String msg = PropertyUtil.getString("PNGImageDecoder2");
                        throw new RuntimeException(msg);
                    }
                    break; // fall through to the bottom
                } else if (chunkType.equals(PNGChunk.ChunkType.bKGD.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_bKGD_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.cHRM.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_cHRM_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.gAMA.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_gAMA_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.hIST.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_hIST_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.iCCP.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_iCCP_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.pHYs.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_pHYs_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.sBIT.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_sBIT_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.sRGB.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_sRGB_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.tEXt.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_tEXt_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.tIME.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_tIME_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.tRNS.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_tRNS_chunk(chunk);
                } else if (chunkType.equals(PNGChunk.ChunkType.zTXt.name())) {
                    chunk = PNGChunk.readChunk(distream);
                    parse_zTXt_chunk(chunk);
                } else {
                    chunk = PNGChunk.readChunk(distream);
                    // Output the chunk data in raw form

                    String type = chunk.getTypeString();
                    byte[] data = chunk.getData();
                    if (encodeParam != null) {
                        encodeParam.addPrivateChunk(type, data);
                    }
                    if (emitProperties) {
                        String key = "chunk_" + chunkIndex++ + ':' + type;
                        properties.put(key.toLowerCase(Locale.getDefault()), data);
                    }
                }
//            } catch (Exception e) {
//                e.printStackTrace();
//                String msg = PropertyUtil.getString("PNGImageDecoder2");
//                throw new RuntimeException(msg);
//            }
        } while (true);

        // Final post-processing

        if (significantBits == null) {
            significantBits = new int[inputBands];
            for (int i = 0; i < inputBands; i++) {
                significantBits[i] = bitDepth;
            }

            if (emitProperties) {
                properties.put("significant_bits", significantBits);
            }
        }
    }