001 /*
002 * Sonar, open source software quality management tool.
003 * Copyright (C) 2008-2012 SonarSource
004 * mailto:contact AT sonarsource DOT com
005 *
006 * Sonar is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * Sonar is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public
017 * License along with Sonar; if not, write to the Free Software
018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02
019 */
020 package org.sonar.api.utils;
021
022 import org.sonar.api.BatchComponent;
023 import org.sonar.api.ServerComponent;
024
025 import java.util.Date;
026
027 /**
028 * A semaphore shared among all the processes that can connect to the central database.
029 * It's ignored when enabling the dry run mode.
030 *
031 * @since 3.4
032 */
033 public interface Semaphores extends BatchComponent, ServerComponent {
034
035 /**
036 * Try to acquire a semaphore for a given duration.
037 * The semaphore is acquired if it's unlocked or if the max locking duration is reached.
038 * When the lock is acquired there will be a periodic ping of the
039 * server to update the semaphore and avoid it to be considered as
040 * outdated.
041 *
042 * @param name the key of the semaphore
043 * @param maxAgeInSeconds the max duration in seconds the semaphore will be considered unlocked if
044 * it was not updated. The value zero forces the semaphore to be acquired, whatever its status.
045 * @param updatePeriodInSeconds the period in seconds the semaphore will be updated.
046 * @return the semaphore, whatever its status (locked or unlocked). Can't be null.
047 */
048 Semaphore acquire(String name, int maxAgeInSeconds, int updatePeriodInSeconds);
049
050 /**
051 * Try to acquire a semaphore.
052 * The semaphore will be acquired only if there's no existing lock.
053 *
054 * @param name the key of the semaphore
055 * @return the semaphore, whatever its status (locked or unlocked). Can't be null.
056 */
057 Semaphore acquire(String name);
058
059 /**
060 * Release the lock on a semaphore by its name. Does nothing if the lock is already released.
061 *
062 * @param name the key of the semaphore
063 */
064 void release(String name);
065
066 class Semaphore {
067
068 private String name;
069 private boolean locked;
070 private Date locketAt;
071 private Date createdAt;
072 private Date updatedAt;
073 private Long durationSinceLocked;
074
075 public String getName() {
076 return name;
077 }
078
079 public Semaphore setName(String name) {
080 this.name = name;
081 return this;
082 }
083
084 public boolean isLocked() {
085 return locked;
086 }
087
088 public Semaphore setLocked(boolean locked) {
089 this.locked = locked;
090 return this;
091 }
092
093 public Date getLocketAt() {
094 return locketAt;
095 }
096
097 public Semaphore setLocketAt(Date locketAt) {
098 this.locketAt = locketAt;
099 return this;
100 }
101
102 public Date getCreatedAt() {
103 return createdAt;
104 }
105
106 public Semaphore setCreatedAt(Date createdAt) {
107 this.createdAt = createdAt;
108 return this;
109 }
110
111 public Date getUpdatedAt() {
112 return updatedAt;
113 }
114
115 public Semaphore setUpdatedAt(Date updatedAt) {
116 this.updatedAt = updatedAt;
117 return this;
118 }
119
120 public Long getDurationSinceLocked() {
121 return durationSinceLocked;
122 }
123
124 public Semaphore setDurationSinceLocked(Long durationSinceLocked) {
125 this.durationSinceLocked = durationSinceLocked;
126 return this;
127 }
128 }
129
130 }