ContentCompression.java

/*
 * myLib - https://github.com/taktod/myLib
 * Copyright (c) 2014 ttProject. All rights reserved.
 * 
 * Licensed under The MIT license.
 */
package com.ttProject.container.mkv.type;

import java.nio.ByteBuffer;

import com.ttProject.container.mkv.MkvMasterTag;
import com.ttProject.container.mkv.MkvTag;
import com.ttProject.container.mkv.Type;
import com.ttProject.container.mkv.type.ContentCompAlgo.Algo;
import com.ttProject.nio.channels.IReadChannel;
import com.ttProject.unit.extra.EbmlValue;

/**
 * ContentEncoding
 * @author taktod
 */
public class ContentCompression extends MkvMasterTag {
	private ContentCompAlgo     algo = null;
	private ContentCompSettings settings = null;
	/**
	 * constructor
	 * @param size
	 */
	public ContentCompression(EbmlValue size) {
		super(Type.ContentEncoding, size);
	}
	/**
	 * constructor
	 */
	public ContentCompression() {
		this(new EbmlValue());
	}
	/**
	 * {@inheritDoc}
	 */
	@Override
	public void load(IReadChannel channel) throws Exception {
		super.load(channel);
		// now we can get the algo and settings.
		for(MkvTag tag : getChildList()) {
			if(tag instanceof ContentCompAlgo) {
				algo = (ContentCompAlgo)tag;
			}
			else if(tag instanceof ContentCompSettings) {
				settings = (ContentCompSettings)tag;
			}
		}
		if(algo == null) {
			throw new Exception("algo setting is required, but not found.");
		}
	}
	/**
	 * {@inheritDoc}
	 */
	@Override
	public void addChild(MkvTag tag) {
		if(tag instanceof ContentCompAlgo) {
			algo = (ContentCompAlgo)tag;
		}
		if(tag instanceof ContentCompSettings) {
			settings = (ContentCompSettings)tag;
		}
		super.addChild(tag);
	}
	/**
	 * {@inheritDoc}
	 */
	@Override
	public MkvTag removeChild(int i) {
		MkvTag removedTag = super.removeChild(i);
		if(removedTag.hashCode() == algo.hashCode()) {
			algo = null;
		}
		if(removedTag.hashCode() == settings.hashCode()) {
			settings = null;
		}
		return removedTag;
	}
	public Algo getAlgoType() throws Exception {
		if(algo == null) {
			throw new Exception("algo is undefined.");
		}
		return algo.getType();
	}
	public ByteBuffer getSettingData() throws Exception {
		if(getAlgoType() != Algo.HeaderStripping) {
			throw new Exception("algoType is unexpected.:" + getAlgoType());
		}
		if(settings == null) {
			throw new Exception("settings is undefined.");
		}
		return settings.getMkvData();
	}
}