class BitRateBox extends AbstractBox {
    public static final String TYPE = "btrt";

    private long bufferSizeDb;
    private long maxBitrate;
    private long avgBitrate;

    public BitRateBox() {
        super(TYPE);
    }

    protected long getContentSize() {
        return 12;
    }

    @Override
    public void _parseDetails(ByteBuffer content) {<FILL_FUNCTION_BODY>}

    @Override
    protected void getContent(ByteBuffer byteBuffer) {
        IsoTypeWriter.writeUInt32(byteBuffer, bufferSizeDb);
        IsoTypeWriter.writeUInt32(byteBuffer, maxBitrate);
        IsoTypeWriter.writeUInt32(byteBuffer, avgBitrate);
    }

    /**
     * Get the size of the decoding buffer for the elementary stream in bytes.
     *
     * @return decoding buffer size
     */
    public long getBufferSizeDb() {
        return bufferSizeDb;
    }

    /**
     * Sets the size of the decoding buffer for the elementary stream in bytes
     *
     * @param bufferSizeDb decoding buffer size
     */
    public void setBufferSizeDb(long bufferSizeDb) {
        this.bufferSizeDb = bufferSizeDb;
    }

    /**
     * gets the maximum rate in bits/second over any window of one second.
     *
     * @return max bit rate
     */
    public long getMaxBitrate() {
        return maxBitrate;
    }

    /**
     * Sets the maximum rate in bits/second over any window of one second.
     *
     * @param maxBitrate max bit rate
     */
    public void setMaxBitrate(long maxBitrate) {
        this.maxBitrate = maxBitrate;
    }

    /**
     * Gets the average rate in bits/second over the entire presentation.
     *
     * @return average bit rate
     */
    public long getAvgBitrate() {
        return avgBitrate;
    }

    /**
     * Sets the average rate in bits/second over the entire presentation.
     *
     * @param avgBitrate the track's average bit rate
     */
    public void setAvgBitrate(long avgBitrate) {
        this.avgBitrate = avgBitrate;
    }
}

        bufferSizeDb = IsoTypeReader.readUInt32(content);
        maxBitrate = IsoTypeReader.readUInt32(content);
        avgBitrate = IsoTypeReader.readUInt32(content);
    
<methods>public void getBox(java.nio.channels.WritableByteChannel) throws java.io.IOException,public long getSize() ,public java.lang.String getType() ,public byte[] getUserType() ,public boolean isParsed() ,public void parse(java.nio.channels.ReadableByteChannel, java.nio.ByteBuffer, long, org.mp4parser.BoxParser) throws java.io.IOException,public final synchronized void parseDetails() <variables>private static org.slf4j.Logger LOG,protected java.nio.ByteBuffer content,private java.nio.ByteBuffer deadBytes,boolean isParsed,protected java.lang.String type,private byte[] userType