TextAWSElasticCacheConfigCommand.java

package net.rubyeye.xmemcached.command.text;

import java.nio.ByteBuffer;
import java.util.concurrent.CountDownLatch;

import com.google.code.yanf4j.buffer.IoBuffer;

import net.rubyeye.xmemcached.command.Command;
import net.rubyeye.xmemcached.command.CommandType;
import net.rubyeye.xmemcached.impl.MemcachedTCPSession;
import net.rubyeye.xmemcached.networking.MemcachedSession;
import net.rubyeye.xmemcached.utils.ByteUtils;

/**
 * AWS ElasticCache config command, see <a href=
 * "http://docs.aws.amazon.com/AmazonElastiCache/latest/UserGuide/AutoDiscovery.AddingToYourClientLibrary.html"
 * >Adding Auto Discovery To Your Client Library</a>. Only supports Cache Engine
 * version 1.4.14 or higher.
 * 
 * @author dennis
 *
 */
public class TextAWSElasticCacheConfigCommand extends Command {

	private String key;

	private String subCommand;

	public TextAWSElasticCacheConfigCommand(final CountDownLatch latch,
			String subCommand, String key) {
		super(subCommand + key, CommandType.AWS_CONFIG, latch);
		this.key = key;
		this.subCommand = subCommand;
		this.result = new StringBuilder();
	}

	@Override
	public boolean decode(MemcachedTCPSession session, ByteBuffer buffer) {
		String line = null;
		while ((line = ByteUtils.nextLine(buffer)) != null) {
			if (line.equals("END")) { // at the end
				return done(session);
			} else if (line.startsWith("CONFIG")) {
				// ignore
			} else {
				((StringBuilder) this.getResult()).append(line);
			}
		}
		return false;
	}

	private final boolean done(MemcachedSession session) {
		setResult(this.getResult().toString());
		countDownLatch();
		return true;
	}

	@Override
	public void encode() {
		// config [sub-command] [key]
		final byte[] subCmdBytes = ByteUtils.getBytes(this.subCommand);
		final byte[] keyBytes = ByteUtils.getBytes(this.key);
		this.ioBuffer = IoBuffer.allocate(6 + 1 + subCmdBytes.length + 1
				+ keyBytes.length + 2);
		ByteUtils.setArguments(this.ioBuffer, "config", subCmdBytes, keyBytes);
		this.ioBuffer.flip();
	}

}