/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use
 * this file except in compliance with the License. You may obtain a copy of the License at the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>Unless required by applicable law or agreed to in writing, software distributed under the
 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apereo.portal.concurrency;

import java.util.Date;
import org.apereo.portal.EntityTypes;

/**
 * Defines a lock associated with an owner and a portal entity that guarantees some degree of
 * exclusive access to the entity, depending on <code>lockType</code> and <code>expirationTime
 * </code>.
 *
 * <p>See IEntityLockService for the rules governing lock assignment and a code example.
 *
 * @see org.apereo.portal.concurrency.IEntityLockService
 */
public interface IEntityLock {

    /**
     * Attempts to change the <code>lockType</code> of this lock to <code>newType</code>. The <code>
     * expirationTime</code> is renewed.
     *
     * @param newType int
     * @exception org.apereo.portal.concurrency.LockingException - if the conversion fails.
     */
    public void convert(int newType) throws LockingException;
    /**
     * Attempts to change the <code>lockType</code> of this lock to <code>newType</code>. The <code>
     * expirationTime</code> is extended <code>newDuration</code> seconds.
     *
     * @param newType int
     * @param newDuration int
     * @exception org.apereo.portal.concurrency.LockingException - if the conversion fails.
     */
    public void convert(int newType, int newDuration) throws LockingException;
    /** @return java.lang.String */
    public String getEntityKey();
    /**
     * @see EntityTypes for known types.
     * @return java.lang.Class
     */
    public Class getEntityType();
    /** @return java.util.Date */
    public Date getExpirationTime();
    /**
     * Could be the portal user or the framework or ...?
     *
     * @return java.lang.String
     */
    public String getLockOwner();
    /**
     * See IEntityLockingService for a description of lock types.
     *
     * @return int
     */
    public int getLockType();
    /** Answers if this lock is still good. */
    public boolean isValid() throws LockingException;
    /** Invalidate the lock. */
    public void release() throws LockingException;
    /** Extends the expiration time of this lock for a service-defined period. */
    public void renew() throws LockingException;
    /** Extends the expiration time of this lock for <code>duration</code> seconds. */
    public void renew(int duration) throws LockingException;
}