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    private void testNinePatch() {
        // String pngName = "addto_bookmarks_bg_complied.9.png";
        String pngName = "barcode_actionbar_pressed_background_complied.9.png";
        try {
            InputStream is = getResources().getAssets().open(pngName);
            // Bitmap bitmap = BitmapFactory.decodeStream(is);
            // byte[] chunkData1 = bitmap.getNinePatchChunk();
            byte[] chunkData2 = loadNinePatchChunk(is);
            NinePatchChunk mChunk = chunkData2 == null ? null : NinePatchChunk
                    .deserialize(chunkData2);
            if (mChunk == null) {
                throw new RuntimeException("invalid nine-patch image: " + pngName);
            }
            printArray(mChunk.mDivX);
            printArray(mChunk.mDivY);
            System.out.println(mChunk.mPaddings.toShortString());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * PNG Chunk struct
     * <a href="http://dev.exiv2.org/projects/exiv2/wiki/The_Metadata_in_PNG_files">The Metadata in PNG files</a>
     * 
     *   +--------+---------+
     *   | Length | 4 bytes |
     *   +--------+---------+
     *   | Chunk  | 4 bytes |
     *   |  type  |         |
     *   +--------+---------+
     *   | Chunk  | Length  |
     *   |  data  |  bytes  |
     *   +--------+---------+
     *   | CRC    | 4 bytes |
     *   +--------+---------+
     *   
     * @param pngName
     * @return chunk
     * @throws IOException
     */
    private byte[] loadNinePatchChunk(InputStream is) throws IOException {
        IntReader reader = new IntReader(is, true);
        // check PNG signature
        // A PNG always starts with an 8-byte signature: 137 80 78 71 13 10 26 10 (decimal values).
        if (reader.readInt() != 0x89504e47 || reader.readInt() != 0x0D0A1A0A) {
            return null;
        }

        while (true) {
            int length = reader.readInt();
            int type = reader.readInt();
            // check for nine patch chunk type (npTc)
            if (type != 0x6E705463) {
                reader.skip(length + 4/*crc*/);
                continue;
            }
            return reader.readByteArray(length);
        }
    }

package com.baidu.luxiaoyu;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import android.graphics.Rect;

/**
 * 
 * See "frameworks/base/include/androidfw/ResourceTypes.h" 
 * for the format of struct Res_png_9patch
 * 
 * @author luxiaoyu01@baidu.com
 * @since 2014-5-6
 * @todo
 */
class NinePatchChunk {
    public Rect mPaddings = new Rect();

    public int  mDivX[];
    public int  mDivY[];
    public int  mColor[];

    private static void readIntArray(int[] data, ByteBuffer buffer) {
        for (int i = 0, n = data.length; i < n; ++i) {
            data[i] = buffer.getInt();
        }
    }

    private static void checkDivCount(int length) {
        if (length == 0 || (length & 0x01) != 0) {
            throw new RuntimeException("invalid nine-patch: " + length);
        }
    }

    public static NinePatchChunk deserialize(byte[] data) {
        ByteBuffer byteBuffer = ByteBuffer.wrap(data).order(ByteOrder.BIG_ENDIAN);

        byte wasSerialized = byteBuffer.get();
        //        if (wasSerialized == 0) return null;

        NinePatchChunk chunk = new NinePatchChunk();
        chunk.mDivX = new int[byteBuffer.get()];
        chunk.mDivY = new int[byteBuffer.get()];
        chunk.mColor = new int[byteBuffer.get()];

        checkDivCount(chunk.mDivX.length);
        checkDivCount(chunk.mDivY.length);

        // skip 8 bytes
        byteBuffer.getInt();
        byteBuffer.getInt();

        chunk.mPaddings.left = byteBuffer.getInt();
        chunk.mPaddings.right = byteBuffer.getInt();
        chunk.mPaddings.top = byteBuffer.getInt();
        chunk.mPaddings.bottom = byteBuffer.getInt();

        // skip 4 bytes
        byteBuffer.getInt();

        readIntArray(chunk.mDivX, byteBuffer);
        readIntArray(chunk.mDivY, byteBuffer);
        readIntArray(chunk.mColor, byteBuffer);

        return chunk;
    }
}

package com.baidu.luxiaoyu;

import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;

/**
 * 
 * Simple helper class that allows reading of integers.
 * 
 * TODO: * implement buffering
 * 
 */
public final class IntReader {

    public IntReader() {
    }

    public IntReader(InputStream stream, boolean bigEndian) {
        reset(stream, bigEndian);
    }

    public final void reset(InputStream stream, boolean bigEndian) {
        m_stream = stream;
        m_bigEndian = bigEndian;
        m_position = 0;
    }

    public final void close() {
        if (m_stream == null) {
            return;
        }
        try {
            m_stream.close();
        } catch (IOException e) {
        }
        reset(null, false);
    }

    public final InputStream getStream() {
        return m_stream;
    }

    public final boolean isBigEndian() {
        return m_bigEndian;
    }

    public final void setBigEndian(boolean bigEndian) {
        m_bigEndian = bigEndian;
    }

    public final int readByte() throws IOException {
        return readInt(1);
    }

    public final int readShort() throws IOException {
        return readInt(2);
    }

    public final int readInt() throws IOException {
        return readInt(4);
    }

    public final int readInt(int length) throws IOException {
        if (length < 0 || length > 4) {
            throw new IllegalArgumentException();
        }
        int result = 0;
        if (m_bigEndian) {
            for (int i = (length - 1) * 8; i >= 0; i -= 8) {
                int b = m_stream.read();
                if (b == -1) {
                    throw new EOFException();
                }
                m_position += 1;
                result |= (b << i);
            }
        } else {
            length *= 8;
            for (int i = 0; i != length; i += 8) {
                int b = m_stream.read();
                if (b == -1) {
                    throw new EOFException();
                }
                m_position += 1;
                result |= (b << i);
            }
        }
        return result;
    }

    public final int[] readIntArray(int length) throws IOException {
        int[] array = new int[length];
        readIntArray(array, 0, length);
        return array;
    }

    public final void readIntArray(int[] array, int offset, int length) throws IOException {
        for (; length > 0; length -= 1) {
            array[offset++] = readInt();
        }
    }

    public final byte[] readByteArray(int length) throws IOException {
        byte[] array = new byte[length];
        int read = m_stream.read(array);
        m_position += read;
        if (read != length) {
            throw new EOFException();
        }
        return array;
    }

    public final void skip(int bytes) throws IOException {
        if (bytes <= 0) {
            return;
        }
        long skipped = m_stream.skip(bytes);
        m_position += skipped;
        if (skipped != bytes) {
            throw new EOFException();
        }
    }

    public final void skipInt() throws IOException {
        skip(4);
    }

    public final int available() throws IOException {
        return m_stream.available();
    }

    public final int getPosition() {
        return m_position;
    }

    /////////////////////////////////// data

    private InputStream m_stream;
    private boolean     m_bigEndian;
    private int         m_position;
}