it.sauronsoftware.cron4j.MemoryTaskCollector Maven / Gradle / Ivy

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/*
 * cron4j - A pure Java cron-like scheduler
 * 
 * Copyright (C) 2007-2010 Carlo Pelliccia (www.sauronsoftware.it)
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version
 * 2.1, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License 2.1 for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License version 2.1 along with this program.
 * If not, see .
 */
package it.sauronsoftware.cron4j;

import java.util.ArrayList;

/**
 * 
 * A {@link TaskCollector} implementation managing a task list in memory.
 * 
 * 
 * @author Carlo Pelliccia
 * @author zhangpengfei
 * @since 2.0
 */
class MemoryTaskCollector implements TaskCollector {

	/**
	 * Size.
	 */
	private int size = 0;

	/**
	 * The inner scheduling pattern list.
	 */
	private ArrayList patterns = new ArrayList();

	/**
	 * The inner task list.
	 */
	private ArrayList tasks = new ArrayList();

	/**
	 * IDs for task-pattern couples.
	 */
	private ArrayList ids = new ArrayList();

	/**
	 * Counts how many task are currently collected by this collector.
	 * 
	 * @return The size of the currently collected task list.
	 */
	public synchronized int size() {
		return size;
	}

	/**
	 * Adds a pattern and a task to the collector.
	 * 
	 * @param pattern
	 *            The scheduling pattern.
	 * @param task
	 *            The task.
	 * @return An ID for the scheduled operation.
	 */
	public synchronized String add(SchedulingPattern pattern, Task task) {
		String id = GUIDGenerator.generate();
		//set task id
		task.setId(id);
		patterns.add(pattern);
		tasks.add(task);
		ids.add(id);
		return id;
	}

	/**
	 * Updates a scheduling pattern in the collector.
	 * 
	 * @param id
	 *            The ID of the scheduled couple.
	 */
	public synchronized void update(String id, SchedulingPattern pattern) {
		int index = ids.indexOf(id);
		if (index > -1) {
			patterns.set(index, pattern);
		}
	}

	/**
	 * Removes a task and its scheduling pattern from the collector.
	 * 
	 * @param id
	 *            The ID of the scheduled couple.
	 */
	public synchronized void remove(String id) throws IndexOutOfBoundsException {
		int index = ids.indexOf(id);
		if (index > -1) {
			tasks.remove(index);
			patterns.remove(index);
			ids.remove(index);
		}
	}

	/**
	 * Retrieves a task from the collector.
	 * 
	 * @param id
	 *            The ID of the scheduled couple.
	 * @return The task with the specified assigned ID, or null if it doesn't
	 *         exist.
	 */
	public synchronized Task getTask(String id) {
		int index = ids.indexOf(id);
		if (index > -1) {
			return (Task) tasks.get(index);
		} else {
			return null;
		}
	}

	/**
	 * Retrieves a scheduling pattern from the collector.
	 * 
	 * @param id
	 *            The ID of the scheduled couple.
	 * @return The scheduling pattern with the specified assigned ID, or null if
	 *         it doesn't exist.
	 */
	public synchronized SchedulingPattern getSchedulingPattern(String id) {
		int index = ids.indexOf(id);
		if (index > -1) {
			return (SchedulingPattern) patterns.get(index);
		} else {
			return null;
		}
	}

	/**
	 * Implements {@link TaskCollector#getTasks()}.
	 */
	public synchronized TaskTable getTasks() {
		TaskTable ret = new TaskTable();
		int size = tasks.size();
		for (int i = 0; i < size; i++) {
			Task t = (Task) tasks.get(i);
			SchedulingPattern p = (SchedulingPattern) patterns.get(i);
			ret.add(p, t);
		}
		return ret;
	}

}