Generator.java

package com.firefly.codec.http2.encode;

import java.nio.ByteBuffer;
import java.util.List;

import com.firefly.codec.http2.frame.DataFrame;
import com.firefly.codec.http2.frame.Frame;
import com.firefly.codec.http2.frame.FrameType;
import com.firefly.codec.http2.hpack.HpackEncoder;
import com.firefly.utils.lang.Pair;

public class Generator {
	private final HeaderGenerator headerGenerator;
	private final HpackEncoder hpackEncoder;
	private final FrameGenerator[] generators;
	private final DataGenerator dataGenerator;

	public Generator() {
		this(4096, 0);
	}

	public Generator(int maxDynamicTableSize, int maxHeaderBlockFragment) {

		headerGenerator = new HeaderGenerator();
		hpackEncoder = new HpackEncoder(maxDynamicTableSize);

		this.generators = new FrameGenerator[FrameType.values().length];
		this.generators[FrameType.HEADERS.getType()] = new HeadersGenerator(headerGenerator, hpackEncoder, maxHeaderBlockFragment);
		this.generators[FrameType.PRIORITY.getType()] = new PriorityGenerator(headerGenerator);
		this.generators[FrameType.RST_STREAM.getType()] = new ResetGenerator(headerGenerator);
		this.generators[FrameType.SETTINGS.getType()] = new SettingsGenerator(headerGenerator);
		this.generators[FrameType.PUSH_PROMISE.getType()] = new PushPromiseGenerator(headerGenerator, hpackEncoder);
		this.generators[FrameType.PING.getType()] = new PingGenerator(headerGenerator);
		this.generators[FrameType.GO_AWAY.getType()] = new GoAwayGenerator(headerGenerator);
		this.generators[FrameType.WINDOW_UPDATE.getType()] = new WindowUpdateGenerator(headerGenerator);
		this.generators[FrameType.CONTINUATION.getType()] = null; // Never generated explicitly.
		this.generators[FrameType.PREFACE.getType()] = new PrefaceGenerator();
		this.generators[FrameType.DISCONNECT.getType()] = new DisconnectGenerator();

		this.dataGenerator = new DataGenerator(headerGenerator);
	}

	public void setHeaderTableSize(int headerTableSize) {
		hpackEncoder.setRemoteMaxDynamicTableSize(headerTableSize);
	}

	public void setMaxFrameSize(int maxFrameSize) {
		headerGenerator.setMaxFrameSize(maxFrameSize);
	}

	@SuppressWarnings("unchecked")
	public <T extends FrameGenerator> T getControlGenerator(FrameType type) {
		return (T) this.generators[type.getType()];
	}
	
	public List<ByteBuffer> control(Frame frame) {
		return generators[frame.getType().getType()].generate(frame);
	}

	public Pair<Integer, List<ByteBuffer>> data(DataFrame frame, int maxLength) {
		return dataGenerator.generate(frame, maxLength);
	}
	
	public void setMaxHeaderListSize(int value) {
        hpackEncoder.setMaxHeaderListSize(value);
    }
}