D-Net

package eu.dnetlib.msro.workflows.sarasvati.registry;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Date;

import java.util.HashMap;

import java.util.Map;

import java.util.Map.Entry;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.annotation.Required;

import com.google.common.collect.BiMap;

import com.google.common.collect.HashBiMap;

import com.googlecode.sarasvati.GraphProcess;

import eu.dnetlib.msro.workflows.util.ProcessUtils;

public class GraphProcessRegistry {

	private static final Log log = LogFactory.getLog(GraphProcessRegistry.class); // NOPMD by marko on 11/24/08 5:02 PM

	private BiMap<String, GraphProcess> procs = HashBiMap.create();

	private Map<String, Collection<GraphProcess>> byResource = new HashMap<String, Collection<GraphProcess>>();

	private int maxSize;

	public GraphProcess findProcess(final String identifier) {

		return procs.get(identifier);

	}

	public Collection<GraphProcess> findProcessesByResource(final String identifier) {

		synchronized (this) {

			final Collection<GraphProcess> res = byResource.get(identifier);

			if (res == null) {

				return new ArrayList<GraphProcess>();

			}

			return res;

		}

	}

	public String associateProcessWithResource(final GraphProcess process, final String identifier) {

		registerProcess(process);

		synchronized (this) {

			final Collection<GraphProcess> processes = findProcessesByResource(identifier);

			processes.add(process);

			byResource.put(identifier, processes);

		}

		return identifier;

	}

	public String registerProcess(final GraphProcess process) {

		if (procs.containsValue(process)) {

			return procs.inverse().get(process);

		}

		final String id = ProcessUtils.generateProcessId();

		if (procs.size() >= maxSize) {

			removeOldestProcess();

		}

		procs.put(id, process);

		log.info("Registered proc " + process.getGraph().getName() + " with id " + id);

		return id;

	}

	public int countRunningWfs() {

		int count = 0;

		for (Entry<String, GraphProcess> e : procs.entrySet()) {

			final GraphProcess proc = e.getValue();

			if (!proc.isComplete() && !proc.isCanceled()) {

				count++;

			}

		}

		return count;

	}

	private void removeOldestProcess() {

		Date oldDate = new Date();

		String oldId = null;

		for (Entry<String, GraphProcess> e : procs.entrySet()) {

			final GraphProcess proc = e.getValue();

			if (proc.isComplete() || proc.isCanceled()) {

				final Date date = ProcessUtils.calculateLastActivityDate(proc);

				if (date.before(oldDate)) {

					oldDate = date;

					oldId = e.getKey();

				}

			}

		}

		if (oldId != null) {

			unregisterProcess(oldId);

		}

	}

	public void unregisterProcess(final String identifier) {

		final GraphProcess process = findProcess(identifier); // NOPMD

		procs.remove(identifier);

		for (final Collection<GraphProcess> processes : byResource.values()) {

			processes.remove(process);

		}

	}

	public Collection<String> listIdentifiers() {

		return procs.keySet();

	}

	public Map<String, Collection<GraphProcess>> getByResource() {

		return byResource;

	}

	public int getMaxSize() {

		return maxSize;

	}

	@Required

	public void setMaxSize(int maxSize) {

		this.maxSize = maxSize;

	}

}